System 2450 Service Manual Part 1 Rev D

LIMITED WARRANTY For a period of two years following the date of delivery, CONMED Corporation warrants the CONMED System 2450™ Electrosurgical Generator against any defects in material or workmanship and will repair or replace (at CONMED’s option) the same without charge, provided that routine maintenance as specified in this manual has been performed using replacement parts approved by CONMED. This warranty is void if the product is used in a manner or for purposes other than intended.

© 2008 CONMED Corporation 525 French Road Utica, New York 13502 U.S.A.

U.S. Patent Numbers 6,830,569 - 6,875,210 - 6,948,503 D552241 and other patents pending. For Technical Service or Return Authorization Phone: 303-699-7600 / 1-800-552-0138 Extension 5274 Fax 303-699-1628 For Customer Service or to order parts phone: 1-800-448-6506 / 315-797-8375 / Fax 315-735-6235 or contact your CONMED Representative. European Authorized Representative MDSS GmbH Schiffgraben 41 D - 30175 Hannover Germany The revision level of this manual is specified by the highest revision letter found on either the inside front cover or enclosed errata pages (if any).

Manual Number 60-2454-ENG Rev. D 02/08 Unit Serial Number_________________________________

Table of Contents & List of Illustrations

Section

Title

Page

1.0 2.0 3.0

General Information ... Refer to Operator’s Manual (60-2451) Specifications ... Refer to Operator’s Manual (60-2451) Theory of Operation ... 3-1

3.1

Mode Descriptions ... 3-1

3.2

System Overview ... 3-1

3.3

Optional System Configurations ... 3-6

4.1 4.2 4.3 4.4 4.5

General Maintenance Information ... 4-1 Maintenance Personnel ... 4-1 Cleaning ... 4-1 Periodic Inspection ... 4-1 Periodic Performance Testing ... 4-1

4.6

System Calibration ... 4-6

4.7

Last Fault Code Retrieval & Clear ... 4-9

4.8

Displaying Optional System Configuration ... 4-9

3.1.1 3.1.2 3.1.3 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7 3.2.8 3.2.9 3.2.10

4.0

Cut Major Modes ... 3-1 Coag Major Modes ... 3-1 Bipolar Major Modes ... 3-1 RF Power Supply (RFPS) ... 3-4 RF Amplifier and Transformer ... 3-4 Electrosurgical Outputs ... 3-4 Activation Command Sensing ... 3-5 Automatic Return Monitor (A.R.M.)... 3-5 System Controllers and Monitor ... 3-5 Low Voltage Power Monitoring ... 3-5 Operator Control Panel ... 3-5 Activation Tones ... 3-6 Activation Relay Connector ... 3-6

Maintenance ... 4-1

4.5.1 Chassis Ground Integrity ... 4-1 4.5.2 Displays, Alarms and Commands ... 4-1 4.5.3 Output Power ... 4-2 4.5.4 RF Leakage Measurement ... 4-3 4.5.5 Line Frequency Leakage ... 4-4 4.5.6 Automatic Return Monitor (A.R.M.) Check ... 4-5 4.5.7 Output Coupling Capacitor Check ... 4-5 4.6.1 4.6.2 4.6.3 4.6.4 4.6.5 4.6.6 4.7.1 4.7.2

Calibration Preliminaries ... 4-6 Selecting the Mode to Calibrate ... 4-6 Calibrating a Monopolar Mode ... 4-8 Calibrating Bipolar Modes ... 4-8 Calibrating A.R.M. ... 4-8 Completing Calibration ... 4-9 Last Fault Code Retrieval ... 4-9 Clearing Last Fault Codes ... 4-9

Section

Title

4.9 4.10

DACview ... 4-12 Troubleshooting ... 4-12

4.11 4.12

Parts Ordering Information ... 4-14 Assembly Breakdown/Parts Access ... 4-15

4.13

Fault Codes ... 4-18

4.10.1

4.12.1 4.12.2 4.12.3 4.12.4 4.12.5

Appx. A

Figure/Title

Page

HVPS Troubleshooting Hints ... 4-14

Top Cover Removal & Replacement ... 4-15 Bezel Removal & Replacement ... 4-16 Control/Display Board Removal & Replacement ... 4-16 Power Board Removal & Replacement ... 4-17 Power Transistor Replacement ... 4-17

Schematics & BOMs ... A-1 Bill of Material: Top Assembly & Chassis... A-1 Bill of Material: Controller PCB Assembly ... A-7 Bill of Material: Power PCB Assembly ... A-13 Page

Figure 3.2 System Block Diagram ... 3-3 Figure 4.1 Calibration Procedure Flow Chart ... 4-7 Figure 4.2 DIP Switch Positions ... 4-11 Figure A.1a Controller PCB (Top)... A-7 Figure A.1b Controller PCB (Bottom) ... A-8 Figure A.2 Power PCB ... A-13 Table 4.1 Monopolar Cut Mode RF Output Power Accuracy ... 4-2 Table 4.2 Monopolar Coag Mode RF Output Power Accuracy ... 4-2 Table 4.3 Bipolar Mode RF Output Power Accuracy ... 4-2 Table 4.4 Allowable RF Leakage Current to Ground ... 4-3 Table 4.5 Allowable RF Leakage Current - Inactive Monopolar Outputs ... 4-4 Table 4.6 Allowable RF Leakage Current - Inactive Bipolar Outputs... 4-4 Table 4.7 Line Frequency Allowable Leakage - Inactive ... 4-4 Table 4.8 Line Frequency Allowable Leakage - Active ... 4-5 Table 4.9 DIP Switch Settings ... 4-10 Table 4.10 DACview Channels ... 4-12 Table 4.11 Troubleshooting ... 4-12 Table 4.12 Fault Codes ... 4-18 Schematic A.1a Controller PCB - Top Sheet ... A-1 Schematic A.1b Controller PCB - Controller Sheet... A-2 Schematic A.1c Controller PCB - Monitor Sheet ... A-3 Schematic A.1d Controller PCB - FPGA Sheet ... A-4 Schematic A.1e Controller PCB - DAC Sheet ... A-5 Schematic A.1f Controller PCB - Display Sheet ... A-6 Schematic A.2a Power PCB - Power Amplifier ... A-9 Schematic A.2b Power PCB - ... A-10 Schematic A.2c Power PCB - ... A-11 Schematic A.2d Power PCB - ... A-12

Theory of Operation Section 3.0

System 2450™ functions and essential circuit information are provided in this section. This section begins with a description of the key parameters for each mode. This is followed by an overview of how the system functions and some key operational information for the modules within the system.

3.1

Mode Descriptions

The key functional parameters for each mode are presented here. Nominal mode specifications are provided in section 1.2.11 of the System 2450 Operators Manual. 3.1.1

Cut Major Modes

Major Mode

Minor Mode

Nominal RF Frequency

Modulation (Number of Modulation (Normal Pulses, Nominal Time On/Off Frequency & Period)

Cut

Pure

400 KHz

None

None

Blend

400 KHz

11 pulses, 28µs / 12µs

25 KHz / 40µs

Hi Blend*

400 KHz

9 pulses, 23µs / 17µs

25 KHz / 40µs

*Hi Blend can be set by a Hospital Qualified Biomedical Technician – see Section 4.8.

3.1.2

Coag Major Modes

Major Mode

Minor Mode

Nominal RF Frequency

Modulation (Number of Modulation (Normal Pulses, Nominal Time On/Off Frequency & Period)

Coag

Standard

495 KHz

Single pulse

40 KHz / 25µs

Spray

495 KHz

Single pulse

20 KHz / 50µs

Standard and Spray Coag modes are fundamentally different from the Cut modes in that the resonant circuit of the RF Amplifier and Transformer combination is excited by the energy of a single pulse, causing the resonant circuit to ring until the energy is dissipated. Spray Coag provides the maximum open circuit voltage for which the system is rated. 3.1.3

Bipolar Major Modes

Major Mode

Minor Mode

Nominal RF Frequency

Modulation (Number of Modulation (Normal Pulses, Nominal Time On/Off Frequency & Period)

Bipolar

Macro

400 KHz

None

None

Micro

400 KHz

None

None

3.2

System Overview

Mains power is converted to electrosurgical output power through the RF Power Supply (RFPS), the RF Amplifier, and the Transformer and Output sections of the system. Mains power is converted to high voltage direct current power in the RFPS to supply the RF Amplifier. This is essentially a power transformer with a power factor corrected regulator. The power factor correction can be enabled or disabled under software control. Pulses generated in the RF Controller are amplified to electrosurgical power and voltage levels in the RF Amplifier and Transformer portions of the power train. Three high-voltage bipolar transistors and a single MOSFET make up the hybrid-cascode RF Amplifier. The hybrid-cascode amplifier is a fast, high-voltage amplifier that can be controlled by the combination of DC voltage (VBASE_PWM) and a fixed amplitude,

3-1

variable pulse width signal (RFGATE). This amplifier is combined through a relay with either the Monopolar output transformer or the Bipolar output transformer to generate electrosurgical power. Electrosurgical power flows from the RF Amplifier / Transformer section to the Output section where the power is switched to the specific electrosurgical outputs. The Output section also has circuitry to detect activations from accessories and the circuitry to perform the Automatic Return Monitor (A.R.M.) function to ensure the integrity of the dispersive electrode connection. The power section also includes a number of output voltage and current sensors that are used by the RF Controller for control of power delivery and by the Monitor to detect errant output conditions. Windings on the Monopolar output transformer and the Bipolar output transformer are the means for sensing output voltage. Separate primary-side current transformers are shared by the bipolar and monopolar channels for control and monitoring of the current. There are also separate current sensors on the monopolar outputs that are used to detect stuck output relays. The RF Controller is a Field Programmable Gate Array (FPGA) that generates the RFGATE and VBASE_PWM RF Amplifier drive signals based upon a comparison of measured parameters and settings-based parameters. The pulse train sequence is a settings-based parameter that is dependent on the selected mode. Target power, current limit, and voltage limit are all settingsbased parameters derived from a load curve that is specific to the selected mode and front panel power setting. The RF Controller samples electrosurgical output current and output voltage from sensors at a 20 Megahertz rate and uses these sampled values to calculate sensed current, sensed voltage, and output power. This high sample rate allows control of the real power delivered to the active accessory and also allows the System 2450 to rapidly adapt to changing loads. The output current, output voltage, and output power are compared with corresponding settings based parameters of current limit, voltage limit, and target power, respectively, and the RF Controller adjusts value of VBASE_PWM in a closed-loop fashion to control these parameters. The RF Controller also provides fixed pulses for RFGATE within each mode-based pulse train sequence.

3-2

The RF Monitor is a Digital Signal Processor (DSP) that is used to monitor the system for safety problems that can result from a variety of conditions. • The Monitor has independent sensors for output voltage and current, which it uses to calculate power for comparison with the power that the RF Controller senses and for comparison with the generator power setting. • To ensure that the correct outputs are activated, the Monitor also independently senses current at each of the outputs, looking for current flow that would indicate electrosurgical power at outputs other than the selected output. • The Monitor senses the audio output to ensure that a tone occurs whenever electrosurgical outputs are active. • The RF Amplifier drive signal is sensed by the Monitor to detect improper frequencies or improper pulse sequences for the selected mode. • The Monitor independently compares the activation signal with that seen by the System Controller to ensure that the activation signal is consistent. The Monitor has the capability to independently disable the electrosurgical output if a problem is detected. The System Controller provides the primary control interface to the user and other outside systems, including the serial interface, the activation relay, tone generation, and displays. Finally, the Display accepts all user input and provides all user feedback. The Display is controlled by the System Controller through a serial interface and illuminates the LED display elements in a time division multiplexed fashion; the illuminated LED display elements are actually on less than half the time. The Display also provides for user input through the buttons on the control panel, including switch de-bouncing and conditioning. Figure 3.2 illustrates the key elements of the system in block diagram form.

Activation Request

Indicators: Activation & Mode

Keyboard Modes / Power

Displays

Activation Relay Connector

ACT RLY

RS232

SPI

AL TONE

Serial Interface Connector

ACT TONE

System Controller

A.R.M RF Output Relays

VARM

Mono

Patient

Bip

RLY DRV RF INH

PFC EN

RF Controller

RF MP VS RF BP VS

RF Amp

RF IS Host Bus

RFDRV

RFHVSup

Tone Mon VBPWM

HV Power Supply

Monitor

HFINH

M ISN

MRF BP VSN

MRF MP VSN

MRF H1 SN MRF HF SN

Figure 3.2 System Block Diagram

3-3

3.2.1

RF Power Supply (RFPS)

The RFPS is comprised a line transformer and a Power Factor Control (PFC) section. The PFC converts Mains power from the transformer to approximately 95 volts D.C. using techniques that ensure the mains current into the supply is sinusoidal and in phase with the mains voltage. By doing so, RMS current and harmonic distortion are reduced. Jumpers on the power board are used to select input line voltage range. A graphic on the power board and on the schematic indicate which jumpers are used for each input voltage range. WARNING: THE RFPS VOLTAGE TAKES SEVERAL SECONDS TO DECAY AFTER THE POWER IS SWITCHED OFF. TO WARN THE SERVICE TECHNICIAN, A RED LED (DS1) ON THE POWER BOARD INDICATES WHEN VOLTAGE IS STILL ON THE BOARD. The System Controller can enable or disable the PFC section of the RFPS. The PFC is normally enabled during operation to ensure a resistive load is presented to the Mains. In addition to the RFPS winding, there is also another secondary winding on the Mains transformer that is rectified and filtered to provide unregulated +25VDC voltage as the input for a +12V switching regulator. The +12V output is then used to supply input voltage to a variety of low-voltage regulators on the controller board. 3.2.2

RF Amplifier and Transformer

The RF Amplifier and Transformer portions use a switch-mode resonant hybrid-cascode amplifier to convert the power from the RFPS to the RF energy necessary for electrosurgery. One may think of the amplifier as a high-speed switch that pulses current through a resonant circuit, which is formed by the monopolar or bipolar transformer together with capacitors that are connected to the transformer primary and secondary windings. The transformers are designed with a good deal of leakage inductance in order to provide inductance for resonating with the capacitors. One Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) is connected in series with three parallel bipolar transistors to provide the switching. The pulses to drive the gate on the MOSFET in this arrangement come from the RF

3-4

Controller (RFGATE). The base connections of the three parallel bipolar transistors are also driven by a signal that originates from the RF Controller (Vbase_PWM). The RFGATE drive pulses provide the basic pulse pattern that is used to form the electrosurgical waveform, and have a set pulse-pattern and pulsewidth for each mode. A drive of several pulses at a frequency that closely matches the resonant frequency of the amplifier characterize Cut and Blend modes, and the output pulses substantially correspond to the drive. Spray and Standard Coag modes, however, are characterized by pulses that occur less frequently where the amplifier is allowed to “ring” at its resonant frequency. Rapid regulation of the output power in this arrangement is provided by VBASE_PWM; as VBASE_PWM is increased, the output power increases. As noted in the RF Controller discussion, the RF Controller compares the output power with the desired power and adjusts the VBASE_PWM to minimize the difference. VBASE_PWM enters the amplifier as a 312 KHz Pulse-Width-Modulated (PWM) signal that is filtered to become a variable DC base drive signal. Finally, the RF Amplifier and Transformer provide capabilities for sensing RF output current and voltage. The voltage sensors that are used for power control and power monitoring are independent windings on the output transformers. The current is also measured on the primary side of the transformers. With proper characterization of the transformer, the controller obtains an accurate representation of the voltage, current, and thus the output power of the system. 3.2.3

Electrosurgical Outputs

Relays are provided to isolate electrosurgical outputs and select which outputs are active. The System Controller selects the appropriate output relays based upon activation command inputs. The Monitor utilizes current sensors implemented on each monopolar electrosurgical output to determine whether current is flowing only to the correct outputs. In the event that current flows in an output that is not selected, the Monitor can independently disable RF. The monitor uses the bipolar primary voltage to sense that the bipolar relay has been activated.

3.2.4

Activation Command Sensing

Each of the Hand Controlled Accessory receptacles incorporate inputs that are used to sense an activation command from the user. Each monopolar hand controlled accessory receptacle has an input for Cut and an input for Coag. The bipolar receptacle incorporates a single activation input. Each of these five inputs is isolated from the other electrosurgical outputs and from other low-level circuitry in the system. All are powered by a multiple output isolated power supply. The footswitch activation inputs on the back panel are configured in a similar way and share one of the isolated power supply outputs. 3.2.5

Automatic Return Monitor (A.R.M.)

The patient return connector interfaces to single and dual dispersive electrodes using a two-pin connector. A.R.M. circuitry uses an actively driven impedance measurement circuit, which allows the System Controller to detect the type of dispersive electrode connected and verify its integrity. 3.2.6

System Controllers and Monitor

Two processors and an FPGA are used for system interface & control, RF control, and system monitor functions. The RF control section consists of a dual-channel architecture with two independent channels where one is used exclusively for RF output control and the other is used for safety monitoring. All of these elements are located on the Control board, along with circuitry for interface with the user. • System Controller (System Microcontroller): A dedicated Microcontroller that handles the entire user interface, Serial Interface, and enables/disables the power factor control section of the RFPS using the PFC_EN signal. The System Controller can also disable the signal used to drive the RF Amplifier and can terminate RF drive at any time without interaction from either the RF Controller or the Monitor. The System Controller is comprised of a standard architecture microprocessor together with portions of the FPGA, which provides interface logic to a variety of signals, independent voltage regulators, a processor supervisory reset circuit, and other interface logic. • RF Controller: An FPGA implementing digital signal processing elements for control

of RF power using the VBASE_PWM and RFGATE outputs. To reduce the effects on the microprocessor circuits on the Control/ Display Board from RF noise at the output, VBASE_PWM and RFGATE are both differential mode signals running between the Control/Display Board and the power section. The RF Controller is capable of disabling RF output power and putting the system into a safe state without any interaction from the Monitor or the System Controller. The RF Controller independently monitors the RF output voltage and current for control purposes through several scaled inputs. The RF Controller is comprised of the major portion of the FPGA, together with circuitry necessary for converting the control signals between analog and digital form. • RF Monitor: A DSP that is dedicated to safety monitoring activities. The Monitor is capable of disabling RF output power and putting the system into a safe state without any interaction from the RF Controller or the System Controller. To ensure that the Monitor can correctly perform its function, the Monitor is resistively isolated from the System Controller and the RF Controller and has independent voltage regulation. The RF Monitor independently monitors a variety of inputs to detect safety problems and has control of disable signals for RF Amplifier drive. The Monitor is comprised of a DSP, together with circuitry necessary for converting the signals monitored between analog and digital form, an FPGA to provide interface logic, independent voltage regulators, isolation resistors and other interface logic. 3.2.7

Low Voltage Power Monitoring

The low voltage power supply is monitored in hardware and resets the processors if it is out of range. The microprocessor supervisory device on the Control/Display Board monitors +3.3V and +1.8V and will reset the system should the levels drop approximately 0.3V. The Control/Display Board has the circuit that will reset the system should the 3.3V supply exceed 3.6V. 3.2.8

Operator Control Panel

• Keyboard: The main operator input device for choosing operating modes and settings is the membrane keyboard panel. Tactile-feedback

3-5

mechanical switches allow the operator to set modes and adjust power settings. • Display Panel: Consists of 7-segment displays and discrete dual colored LED’s that will display all controls and settings. LED display elements are illuminated in a time division multiplexed fashion; the illuminated LED display elements are actually on less than half the time. 3.2.9

Activation Tones

Tone is generated for all activation requests, fault detection and changes made on the Control Panel. The System Controller generates the tone signal (TONE_DRV), which is amplified by a driver. The activation tone is adjustable and controlled by an output from the System Controller, but alarm tones are not adjustable and are set to generate a tone greater than 65 dB. There is circuitry to permit the Monitor to verify the oscillation from voltage measured across the speaker, which provides confirmation that the speaker is indeed generating audible tones during activation. RF output is inhibited should the speaker drive current be absent or too low. 3.2.10 Activation Relay Connector There is an Accessory Relay Connector, which provides a relay closure (SPST switch) that may be used for activating external accessories such as smoke evacuation units.

3-6

3.3

Optional System Configurations

An eight-position configuration dipswitch (S2), located on the Control/Display Board Assembly (A4) allows a qualified service technician to change some of the factory default settings. With the exception of the DACview switch, which is only effective in Test Mode, the configuration dipswitch settings are only detected when power is initialized, so any changes to the switch positions will not be detected until power is cycled. Each switch is OFF in the Down position and ON in the UP position. (The system detects changes in the DACview switch while power is on, so it is treated differently.) Relevant information for the configuration dipswitches appears in Section 4.8.

Maintenance Section 4.0

This section contains information useful in the maintenance and repair of the System 2450. WARNING: High voltages are present at the connections and within the System 2450. Maintenance personnel should take precautions to protect themselves. Read the safety summary in Section 1.1.4 of the System 2450 Operators Manual before working on the ESU.

4.1

General Maintenance Information

Although the System 2450 has been designed and manufactured to high industry standards, it is recommended that periodic inspection and performance testing be performed to ensure continual safe and effective operation. Ease of maintenance was a primary consideration in the design of the System 2450. Maintenance features of this unit include microprocessor aided troubleshooting aids and push button calibration, built in fault detection, circuit protection, and easy access to circuitry while the unit is operational. These features, coupled with the warranty, local support, loaner equipment, factory support, toll free phone service to the factory and available factory training ensure a minimal maintenance effort with extensive support available.

4.2

Maintenance Personnel

Only Hospital Qualified Biomedical Technicians or ConMed factory technicians should perform service on the System 2450. Refer all servicing to a Hospital Qualified Biomedical Technician. If necessary, your CONMED sales representative will be happy to assist you in getting your equipment serviced.

4.3

Cleaning

The interior of the unit may be vacuumed or blown out as required. The exterior of the unit may be cleaned by wiping it with a cloth that has been dampened (not dripping) with a mild detergent such as Windex® or Formula 409®.

(Windex® is a registered trademark of the S.C. Johnson Company. Formula 409® is a registered trademark of the Clorox Company.)

4.4

Periodic Inspection

The System 2450 should be visually inspected at least every six months. This inspection should include checks for the following: 1) Damage to the power cord and plug. 2) Proper mating and absence of damage to the accessory connectors. 3) Any obvious external or internal damage to the unit. 4) Any accumulation of lint or debris within the unit or heatsink. 5) Control Panel cuts, punctures, or dents.

4.5

Periodic Performance Testing

The System 2450 should be tested for correct performance at least once every year. Every unit is supplied with a serialized Production Test Data Sheet that tabulates the results of the factory tests that were performed on the unit. This data is supplied so that it may be used as a reference for subsequent tests. Recommended periodic performance tests are listed in the following sections. 4.5.1

Chassis Ground Integrity

Connect a standard ohmmeter between the earth ground prong on the power plug and the Equipotential Ground Connection. Compensate for lead resistance. Confirm less than 0.2 ohms resistance is measured. 4.5.2

Displays, Alarms and Commands

Perform the Preliminary Functional Test procedure described in section 2.3.1 of the System 2450 Operators Manual to verify proper operation of displays, alarms and commands.

4-1

4.5.3

Output Power

used for checking power to obtain the best results.

1) Equipment Requirements: a) Monopolar Footswitch b) Bipolar Footswitch c) Commercial ESU Tester (e.g. Fluke 454A or equivalent) with non-inductive 50 and 300 ohm loads for bipolar modes and a non-inductive 500 ohm load for monopolar modes. Note: Micro Bipolar is particularly sensitive to the load resistance. A 50 ohm load should be

2) Use test leads to connect the ESU tester to the unit’s return electrode output and the footswitch controlled active output. Set the Load resistance per mode as indicated in Tables 4.1 and 4.2. 3) Perform the monopolar power tests indicated in Tables 4.1 and 4.2. The acceptance range is given in both Watts and Amps to accommodate available test equipment. It is not necessary to test for both power and current.

Table 4.1 Monopolar Cut Mode RF Output Power Accuracy Mode

Load (ohms) Power Setting Watts (min) Watts (max)

Amps (min)

Amps (max)

Pure

500

20

17

23

0.184

0.214

500

100

90

110

0.424

0.469

500

300

270

330

0.735

0.812

500

20

17

23

0.184

0.214

500

100

90

110

0.424

0.469

200

180

220

0.600

0.663

Blend

500

Table 4.2 Monopolar Coag Mode RF Output Power Accuracy Mode

Load (ohms) Power Setting Watts (min) Watts (max)

Amps (min)

Amps (max)

Standard

500

20

17

23

0.184

0.214

500

50

45

55

0.300

0.332

500

120

108

132

0.465

0.514

500

20

17

23

0.184

0.214

500

50

45

55

0.300

0.332

500

80

72

88

0.379

0.420

Spray

4) Disconnect the ESU tester from the unit.

6) Perform the bipolar power tests indicated in Table 4.3. This table only provides the minimum number of points to be tested.

5) Use test leads to connect the ESU tester to the Bipolar Accessory outputs.

Table 4.3 Bipolar Mode RF Output Power Accuracy Mode

Load (ohms) Power Setting Watts (min) Watts (max)

Amps (min)

Amps (max)

Macro

300

20

17

23

0.238

0.277

300

50

45

55

0.387

0.428

300

70

63

77

0.458

0.507

50

20

17

23

0.583

0.678

50

50

45

55

0.949

1.049

50

70

63

77

1.122

1.241

Spray

4-2

4.5.4

RF Leakage Measurement

NOTE: To ensure accuracy when making leakage measurements, perform all leakage testing using methods and instruments that are compliant with the prcedures outlined in Section 19 of IEC60601-2-2 (Particular Requirements for the Safety of High Frequency Surgical Equipment). RF Leakage can present a hazard in the operating room because electrosurgical currents can flow

to the patient and operating room staff through unintended paths, which can cause injury. RF leakage occurs because the total energy in the output voltage waveform is provided with a conductive path through stray parasitic capacitance distributed within the generator and along the length of the leads. Table 4.4 presents the allowed RF leakage currents to ground.

Table 4.4 Allowable RF Leakage Current to Ground MEASURED TERMINAL

ACTIVATED ACCESSORY

MODE

RF LEAKAGE (Ma)

Dispersive Electrode

Coag Combination Monopolar

Standard Coag

< 100

Dispersive Electrode

Cut Combination Monopolar

Pure Cut

< 100

Dispersive Electrode

Hand Controlled

Standard Coag

< 100

Combination Monopolar Active

Coag Combination Monopolar

Standard Coag

< 100

Hand Controlled Active

Left Hand Controlled

Standard Coag

< 100

Bipolar Right

Bipolar Footswitch

Bipolar Macro

< 67

Bipolar Left

Bipolar Footswitch

Bipolar Macro

< 67

Equipment: • ESU Tester with RF Leakage function -OR• 0-250 is RF Ammeter with a 200 ohm 10 W Non-inductive Resistor • Patient Plate Adapter Plug • 2 - Test leads, 1 m max. Length • 3 - Test leads, 10 cm max. Length • Wooden table approximately 1 m from floor. NOTE: Use a measuring device that meets IEC specification for RMS measured over one second. Procedure: 1) Ensure that the unit is fully assembled and all fasteners are tight. 2) Place the ESU tester or meter with resistor on the table so that they are at least 0.5m away from the unit under test and any other conductive surface. 3) Set the unit for full power for the modes noted in the table. Connect the ESU tester in accordance with the manufacturer’s instructions -OR- connect the 200-ohm noninductive resistor in series with the 250 mA RF ammeter to the Equipotential Ground Connection on the Rear Panel. Also make sure there are no connections to any output other than the one you are measuring.

WARNING: HAND CONTROL ACTIVATIONS SHOULD BE KEYED USING 3” OR LESS WELL-INSULATED JUMPER. USE OF AN INSULATING ROD TO INSERT THE JUMPER IS ADVISED TO PREVENT RF BURNS. 3) One at a time, connect test setup to each RF output terminal indicated in Table 4.4 and activate the unit using the corresponding command. Confirm no meter readings exceed the specified maximum. Hand controlled Coag activations are accomplished by connecting a jumper between the left jack and center jack of the desired hand switched accessory jack. RF leakage should also be measured between inactive outputs and the Dispersive Electrode connection. The procedure is as follows: 1) Set the unit for full power for the modes noted in Table 4.5. Connect the ESU tester according to manufacturer’s instructions - OR- the 200-ohm non-inductive resistor in series with the 250 mA RF ammeter to the Dispersive Electrode connection on the front panel. Also make sure there are no connections to any output other than the one you are measuring.

4-3

2) One at a time, connect this series combination to each RF output terminal indicated in Table 4.5 and activate the unit using the corresponding command. Confirm that no meter readings exceed the specified maximum. Table 4.5 Allowable RF Leakage Current - Inactive Monopolar Outputs MEASURED TERMINAL

ACTIVATED ACCESSORY

MODE

RF LEAKAGE (Ma)

Combination Monopolar Active

Hand Controlled

Standard Coag

< 50

Combination Monopolar Active

Bipolar Footswitched

Macro

< 20

Hand Controlled Active

Combination Monopolar

Standard Coag

< 50

Hand Controlled Active

Bipolar Footswitched

Macro

< 20

Bipolar Left

Right Hand Controlled Standard

Coag

< 48

Finally, RF leakage should be measured between the inactive bipolar outputs while a monopolar accessory is activated. Do the following: 1) Set the unit for full power for the bipolar mode noted in Table 4.6. Connect ESU tester

according to manufacturer’s instructions -OR the 200-ohm non-inductive resistor in series with the 250 mA RF ammeter between the two bipolar output connections. 2) Activate and verify the limit in Table 4.6.

Table 4.6 Allowable RF Leakage Current - Inactive Bipolar Outputs MEASURED TERMINAL

ACTIVATED ACCESSORY

MODE

RF LEAKAGE (Ma)

Bipolar Right to Left

Hand Controlled

Standard Coag

< 48

4.5.5 Line Frequency Leakage CAUTION: To prevent RF current from destroying the test equipment and/or affecting leakage readings, set all power settings to zero. WARNING: ELECTROCUTION HAZARD. USE OF AN ISOLATED MAINS POWER SOURCE IS RECOMMENDED WHEN OPENING THE MAINS GROUND DURING THE FOLLOWING SAFETY TESTS.

Circuit ground and Neutral (Low Mains) must be connected together for Mains leakage testing. Equipment: These tests are performed most conveniently using any good quality biomedical electrical safety tester. Procedure: 1) Connect the electrical safety analyzer to make the measurements indicated in Table 4.7. 2) Mode: Measure leakage for Bipolar to Neutral and Chassis to Neutral.

Table 4.7 Line Frequency Allowable Leakage - Inactive RF output to Neutral

LINE

GND

LIMIT max

Equipotential Ground

Normal

Closed

30 µA

Equipotential Ground

Reversed

Closed

30 µA

Equipotential Ground

Normal

Open

270 µA

Equipotential Ground

Reversed

Open

270 µA

Dispersive Electrode

Normal

Closed

15 µA

Dispersive Electrode

Reversed

Closed

15 µA

Dispersive Electrode

Normal

Open

15 µA

Dispersive Electrode

Reversed

Open

15 µA

Bipolar Output*

Normal

Closed

15 µA

Bipolar Output*

Reversed

Closed

15 µA

Bipolar Output*

Normal

Open

15 µA

Bipolar Output* Reversed Open 15 µA *Measure the Bipolar Output with Bipolar connections shorted together.

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5) Since the System 2450 monopolar active outputs are disconnected by relays when the unit is not activated, active-to-neutral leakage tests must be performed with the unit activated in order to be valid. 6) With all power controls set to zero, measure the leakage current as in step 1 from each of the three active output terminals to neutral;

see Table 4.8; while that output is activated in Cut by the appropriate footswitch or hand control jumper. Hand control cut activations are accomplished by connecting a jumper between the two outer jacks of where the handcontrolled accessory is plugged into the unit.

Table 4.8 Line Frequency Allowable Leakage - Active RF output to Neutral

LINE

GND

ACTIVATION

LIMIT max

Combination Monopolar Active

Normal

Closed

Combination Monopolar Cut

15 µA

Combination Monopolar Active

Reversed

Closed

Combination Monopolar Cut

15 µA

Combination Monopolar Active

Normal

Open

Combination Monopolar Cut

15 µA

Combination Monopolar Active

Reversed

Open

Combination Monopolar Cut

15 µA

Hand Controlled Active

Normal

Closed

Hand Controlled Cut

15 µA

Hand Controlled Active

Reversed

Closed

Hand Controlled Cut

15 µA

Hand Controlled Active

Normal

Open

Hand Controlled Cut

15 µA

Hand Controlled Active

Reversed

Open

Hand Controlled Cut

15 µA

4.5.6 Automatic Return Monitor (A.R.M.) Check A.R.M. has two specific ranges that will be tested initially and then the circuit will be tested to verify that the circuit measures dispersive electrode resistance correctly. For this testing, only a Decade Resistance Box (DRB) and a dispersive electrode cable adapter are required. Connect the DRB to the Dispersive Electrode Receptacle using the dispersive electrode cable adapter. A.R.M. may be reset by disconnecting the dispersive electrode connector or adjusting the DRB above 10K Ohms until the Single and Dual Dispersive Electrode Status/Alarm Indicators flash red in alternating fashion. Allow approximately two seconds after the DRB is changed before proceeding to the next step in the procedure. A.R.M. indicators not mentioned in the procedure must be off for each test. 1) Dual Electrode Alarm Limit: Set the DRB to 158 Ohms, then connect it to the Dispersive Electrode Receptacle and verify that the Single and Dual Dispersive Electrode Status/ Alarm Indicators flash red in alternating fashion. 2) Dual Electrode Upper Limit: Set DRB to 140 Ohms and verify that the Dual Dispersive Electrode Status/Alarm Indicator is Green.

3) Dual Electrode Lower Limit: Set the DRB to 15 Ohms and verify the Dual Dispersive Electrode Status/Alarm Indicator is Green. 4) Single Electrode Upper Limit: Set the DRB to 7 Ohms, then reset A.R.M. and verify the Single Dispersive Electrode Status/Alarm Indicator is Green. 4.5.7

Output Coupling Capacitor Check

WARNING: ENSURE ALL POWER SETTINGS ARE AT 0 WATTS BEFORE CONDUCTING THIS TEST TO PREVENT INJURY TO PERSONNEL AND DAMAGE TO TEST EQUIPMENT. NOTE: Not all capacitance meters will read properly for this test. The test frequency should be at or below 1 kHz for best accuracy. The following meters have been tried successfully: Fluke 189, Extech 285, Sencor LC75 and HP4284A (1 kHz setting or below). 1) Connect shorting plug to banana adapter to the two pin Dispersive Electrode Receptacle. Use 6” or shorter test leads to connect a capacitance meter between the shorting plug adapter and the footswitched ReadiPlug Universal Accessory Receptacle. 2) Measure capacitance and confirm it is less than 0.2 nF.

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3) Confirm cut power is set to 0, then activate and confirm capacitance is between 0.6 and 0.9 nF. 4) Do not activate for this bipolar test. Move test leads to Bipolar Output Accessory Receptacles. Confirm capacitance is between 2.2 and 2.5 nF.

4.6

System Calibration

The System 2450 is calibrated during manufacture using equipment traceable to National Institute of Standards & Technology (NIST) standards and should retain its accuracy for a long period of time. Recalibrate the generator after repair or if it performs out of specification. Check the calibration in normal operating mode and only perform calibration if errors are identified. The System 2450 stores its calibration in nonvolatile semiconductor memory, so the calibration will be retained without any action on the part of the user or maintenance staff. Calibration should be checked in normal operating mode during annual preventative maintenance to ensure there is no change. Calibration is required when: • “Err 138”, “Err 139”, or “Err 140” occurs: An error is detected with the stored calibration values. • “Err 143” or “Err 321” occurs: One or more modes require calibration. • “Err 135” occurs: An error is detected with stored ARM calibration values. • Either the Control/Display Board assembly (Conmed P/N 61-6991) or the Power Board assembly (Conmed P/N 61-6981) is replaced.

positions will not affect this. See Section 4.8 for system configuration DIP switch details. With this configuration set, turn on power while pressing and holding both Bipolar Mode Select Keys. Release these Keys when CAL appears in the Monopolar Cut Power Digital Display and the software revision appears in the Monopolar Coag Power Digital Display. CAL and the software revision may persist in the displays for a few seconds after the Bipolar Mode Select Keys are released. The display will then provide an indication of the calibration status: • “ALL” will appear in the Monopolar Cut Power Digital Display if the calibration memory is empty. • “nEr” will appear in the Monopolar Cut Power Digital Display, where “n” indicates how many major modes require calibration, will be displayed if only particular modes require calibration. All of the minor mode indicators will be illuminated and the minor modes needing calibration will flash. • “[U”, “[0A”, “bP”, or “Pad” will appear in the Monopolar Cut Power Digital Display to indicate the major mode when only minor modes under that major mode require calibration. All of the minor mode indicators will be illuminated and the minor modes needing calibration will flash. • “[U” will appear in the Monopolar Cut Power Digital Display with the Pure Cut Mode Indicator illuminated if all modes are calibrated.

Refer to Figure 4.1 for calibration process flow.

For all except the last of these, a single Press and release of the Tone Loudness Adjustment Down Key is required to proceed past this point on the menu. After pressing this key, “[U” will appear in the Monopolar Cut Power Digital Display with the Pure Cut Mode Indicator illuminated.

4.6.1

4.6.2

• Calibration differences are found during preventative maintenance. Calibration Preliminaries

System 2450 calibration occurs in Calibration Operating Mode, which is entered by setting the system configuration DIP switches on the Control/Display Board. Set the Calibration system configuration DIP switch (Control/Display Board SW2.2) to the ON (UP) position and the Test system configuration DIP switch (Control/ Display Board SW2.1) to the OFF (DOWN) position. Other configuration DIP switch settings

4-6

Selecting the Mode to Calibrate

Press the Monopolar Cut Power Adjustment Keys to select the major mode to calibrate as displayed in the Monopolar Cut Power Digital Display. The selections are “[U” for Cut, “[0A” for Coag, “Bp” for Bipolar, or “PAd” for the Dispersive Electrode A.R.M. connection. If any of the minor modes under these major modes are not calibrated, the displayed major mode will flash. Select the monopolar minor mode by pressing the appropriate Mode Select Key.

Calibration Set the Calibration System Configuration Dipswitch on the Controller to the ON position Turn main power switch on while pressing both Bipolar Mode Select Keys. Release Bipolar Mode Select Keys when the Monopolar Cut Power Digital Display indicates “ [AL”

[AL rxx

ALL

[u 500 P

2Er

3Er

[u

[0A

bP

PAd

Press Tone Loudness Adjustment Down Key

Press Monopolar Cut Power Adjustment Keys to select [u, [0A, bP and PAd. [u

[0A

bP

Pad 10

Press Cut Minor Mode Select Key for Pure or Blend.

Press Coag Minor Mode Select Key for Spray or Standard

Press Bipolar Minor Mode Select Key for Macro or Micro

Press Tone Loudness Adjustment Down Key

Connect indicated load with meter to output Press Tone Loudness Adjustment Down Key *

Activate when target level displayed. Press Monopolar Coag Power Adjustment keys to match power/current to Calibration Target. Minimum activation 2 seconds, release. Press Tone Loudness Adjustment Down Key.

Connect 10 ohm load Two-Pin Dispersive Electrode Receptacle Press Bipolar Power Adjustment Key Press Monopolar Coag Power Adjustment Key PAd 150

Connect 150 ohm load Two-Pin Dispersive Electrode Receptacle. Press Bipolar Power Adjustment Key.

Power off

Set the Calibration System Configuration Dipswitch on the Controller to the OFF position

End

*Dashed line indicates second step of Blend mode calibration.

Figure 4.1 Calibration Procedure Flow Chart

4-7

4.6.3

Calibrating a Monopolar Mode

This section applies to the Pure Cut, Blend, Standard Coag, and Spray Coag modes. Calibration may be performed by measuring current or by measuring power. To select between calibration using measured current and measured power, press the Bipolar Power Adjustment Keys to set the calibration units to either “A” for current or “P” for power. The resistance to be used for calibration will appear in the Monopolar Coag Power Digital Display. Connect a resistor of this value between the output connection that is being used for calibration and both pins on the Two-Pin Dispersive Electrode Receptacle. Press and release the Tone Loudness Adjustment Down Key to begin calibration. After this key is pressed, the target level appears in the Monopolar Coag Power Digital Display. Activate using the appropriate Handswitch or Footswitch. Power will now flow to the resistor. While monitoring either the current or the power, adjust the power up or down using the Monopolar Coag Power Adjustment Keys until the measured value is as close to the target level as possible. The activation must be maintained for a minimum of 2 seconds to ensure the calibration is valid. After the power is properly adjusted, release the activation. Press and release the Tone Loudness Adjustment Down Key to complete the calibration sequence for the selected minor mode. *Blend mode only: Both the default Lo Blend mode and the optional Hi Blend mode must be calibrated. After Lo Blend is calibrated, the system will return to the step where the target power is displayed for Hi Blend calibration. Note that the target value for Hi Blend is different from the target value for Lo Blend. To complete the Hi Blend calibration, activate again using the appropriate Handswitch or Footswitch. Power will now flow to the resistor. While monitoring either the current or the power, adjust the power up or down using the Monopolar Coag Power Adjustment Keys until the measured value is as close to the target level as possible. The activation must be maintained for a minimum of 2 seconds to ensure the calibration is valid. After the power is properly adjusted, release the activation. Press and release the Tone Loudness Adjustment Down Key to complete the Hi Blend calibration sequence.

4-8

After a minor mode has been calibrated, the associated minor mode indicator will quit flashing. When all of the minor modes within a major mode have been calibrated, the major mode indicated in the Monopolar Cut Power Digital Display will quit flashing. 4.6.4

Calibrating Bipolar Modes

The Bipolar modes are calibrated using a method that is very similar to the Monopolar modes. Calibration may be performed by measuring current or by measuring power. To select between calibration using measured current and measured power, press the Bipolar Power Adjustment Keys to set the calibration units to either “A” for current or “P” for power. The resistance to be used for calibration will appear in the Monopolar Coag Power Digital Display. Connect a resistor of this value between the two active connections in the Bipolar Accessory Receptacle. Press and release the Tone Loudness Adjustment Down Key to begin calibration. After this key is pressed, the target level appears in the Monopolar Coag Power Digital Display. Activate using the Bipolar Footswitch. Power will now flow to the resistor. While monitoring either the current or the power, adjust the power up or down using the Monopolar Coag Power Adjustment Keys until the measured value is as close to the target level as possible. The activation must be maintained for a minimum of 2 seconds to ensure the calibration is valid. After the power is properly adjusted, release the activation. Press and release the Tone Loudness Adjustment Down Key to complete the calibration sequence for the bipolar mode. After a Bipolar minor mode has been calibrated, the associated Bipolar minor mode indicator will quit flashing. When all of the Bipolar minor modes have been calibrated, the major mode indicated in the Monopolar Cut Power Digital Display will quit flashing. 4.6.5

Calibrating A.R.M.

A.R.M. is calibrated against a pair of known resistances. Press and release the Tone Loudness Adjustment Down Key to begin calibration. The resistance to be used for calibration will appear in the Monopolar Coag Power Digital Display. Connect

a resistor of this value ±1% between the two active connections in the Two-Pin Dispersive Electrode Receptacle. Calibrate the particular value connected by pressing one of the Bipolar Power Adjustment Keys. When the value is accepted, a two-tone sequence will sound and the resistance in the Monopolar Coag Power Digital Display will quit flashing. Now scroll to the other of the pair of known resistances using the Monopolar Coag Power Adjustment Keys. The resistance to be used for calibration will appear in the Monopolar Coag Power Digital Display. Connect a resistor of this value ±1% between the two active connections in the Two-Pin Dispersive Electrode Receptacle. Calibrate the particular value connected by again pressing one of the Bipolar Power Adjustment Keys. When the value is accepted, a two-tone sequence will sound and the resistance in the Monopolar Coag Power Digital Display will quit flashing.

a few seconds after the Bipolar Mode Select Keys are released. This action will place the system in the Last Fault Code Mode (LFC). Electrosurgical outputs cannot be activated while the system is in LFC. 2) If any errors are stored in memory, the Cut Window will next display “Err”; the Coag window will display the error code (a numeric value); and the Bipolar Window will display the storage location of that error code. Last Fault display example:

Err

381

1

3) Scroll through the stored error codes using the Bipolar Power Adjustment Keys. The error codes are stored Last in, First out. A “1” in the Bipolar Display shows the last error that occurred. Press the Bipolar Up key and a “2” will be displayed if more than one error occurred.

After A.R.M. has been calibrated, the major mode “PAd” indicated in the Monopolar Cut Power Digital Display will quit flashing.

4) To retrieve the settings when the error occurred, it is necessary to have a Handcontrol accessory connected. Press both Cut and Coag activation switches and the Display Panel will show the system settings when the error occurred.

4.6.6

4.7.2

Press and release the Tone Loudness Adjustment Down Key to complete A.R.M. calibration.

Completing Calibration

Turn power off and set the Calibration system configuration DIP switch (Control/Display Board SW2.2) to the OFF (DOWN) position. See Section 4.8 Displaying Optional System Configuration for system configuration DIP switch details. The ESU will be ready for normal operation the next time the power is turned on.

4.7

Last Fault Code Retrieval & Clear

Up to 50 error (Err) and accessory (A[[) codes can be stored in memory for retrieval. When retrieving the error codes, it is also possible to retrieve the system settings when the error occurred. 4.7.1

Last Fault Code Retrieval

1) Turn on power while pressing and holding both Bipolar Mode Select Keys. Release these Keys when LF[ appears in the Monopolar Cut Power Digital Display and the software revision appears in the Monopolar Coag Power Digital Display. LF[ and the software revision may persist in the displays for

Clearing Last Fault Codes

As errors occur, fault codes from earlier errors are erased in a last-in-first-out fashion. While it is not absolutely necessary to clear the older codes, clearing the codes may be desirable in some situations. • Pressing the Monopolar Cut Power Adjustment down Key followed by the Tone Loudness Adjustment Down Key will clear the entire fault code memory. The cut window will display “[Lr” when codes are cleared. • Pressing the Tone Loudness Adjustment Down Key again will display the optional system configuration settings.

4.8 Displaying Optional System Configuration The optional system configuration DIP switch settings can be checked without removing the top cover. • Access Last Fault Code retrieval as described in the preceding section.

4-9

• Press the Tone Loudness Adjustment Down Key again and the configuration DIP switch settings will be displayed. “0” is for OFF and a “1” is for ON. The eight-position configuration DIP switch (S2), located on the Control/Display Board Assembly allows a qualified service technician to change some of the factory default settings. The default

switch is only read during Power on Self Test (POST) or when the system is powered on, so any changes to the switch positions should be made with the main power off. Each switch is OFF in the down position and ON in the up position. Relevant information for each switch is described in Table 4.9 and the positions are illustrated in Figure 4.2.

Table 4.9 DIP Switch Settings Config. Title / Display Element Switch Position

Default

Description for Off

Description for On

1

TEST / Cut 100’s

Off

Run Mode. Required position for surgery.

Activates Test Mode, which inhibits most of the system level monitoring for troubleshooting purposes. When this switch is ON, both Bipolar Mode Select Keys on the Display Panel must be pressed until 888 appears in the Monopolar Cut Power Digital Display and the software revision appears in the Monopolar Coag Power Digital Display. 888 and the software revision may persist in the displays for a few seconds after the Bipolar Mode Select Keys are released. If both Bipolar Mode Select Keys are not pressed, and Err 100 is displayed and the power must be cycled.

2

CAL/ Cut 10’s

Off

Run Mode. Required position for surgery.

Required for calibration of output power and A.R.M. When this switch is ON, both Bipolar Mode Select Keys on the Display Panel must be pressed until [AL appears in the Monopolar Cut Power Digital Display and the software revision appears in the Monopolar Coag Power Digital Display. [AL and the software revision may persist in the displays for a few seconds after the Bipolar Mode Select Keys are released. If both Bipolar Mode Select Keys are not pressed, and Err 100 is displayed and the power must be cycled.

3

SCOAG / Cut 1’s

On

Allows activation of only one accessory at a time in Coagulation modes.

Allows simultaneous activation of two accessories for Coagulation modes.

4

DCUT / Coag 100’s

Off

Allows activation of only one accessory at a time in Cut modes.

Allows simultaneous activation of two accessories for Cut modes.

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