Medtronic Valleylab Force FX

Asset Type

Electrosurgical Unit (ESU)

Manufacturer

Medtronic

Model

Valleylab Force FX

Manual Reference

Force FX-8C Electrosurgical Generator Service Manual, Valleylab Part Number 945 103 068, Effective Date September 2000.

Manufacturer Recommendation / AEM Status

Manufacturer-listed PM items

The service manual lists a Periodic Safety Check to be performed every six months to verify that the generator is functioning properly.

The manual-listed safety check includes:

• Inspect the generator and accessories.
• Inspect internal components.
• Test the generator self-test.
• Verify REM function.
• Confirm outputs.
• Check leakage current and ground resistance.

Manufacturer-listed frequency

Every six months.

The manual also states output confirmation should be performed after calibration and every six months.

High-frequency leakage current is also listed to be checked after calibration and every six months.

Manufacturer-listed post-service / return-to-service checks

The manual states low-frequency leakage current and ground resistance should be checked before returning the Force FX-8C generator to clinical use.

AEM note

If a facility performs this PM at a different interval or changes the listed activities, that should be handled under the facility’s approved AEM program, risk assessment, maintenance history, and applicable regulatory requirements.

What This PM Procedure Covers

• Visual inspection of generator, power cord, receptacles, and accessories.
• Internal inspection where facility policy allows.
• Power-on self-test verification.
• REM function verification.
• Bipolar, monopolar cut, and monopolar coag output checks.
• Low-frequency leakage current checks.
• High-frequency RF leakage checks.
• CMMS-ready documentation.

Required Tools and Equipment

Manufacturer-listed test equipment includes:

• Digital voltmeter, Fluke 77 or 87 or equivalent.
• True RMS voltmeter, Fluke 8920 or equivalent.
• Oscilloscope, Tektronix 2445 or equivalent.
• Leakage current tester or UL load device.
• Leakage table per IEC 601-2-2, Figure 104.
• 100 Ω, 200 Ω, 300 Ω, and 500 Ω, 250 W, 1% tolerance, noninductive resistors.
• Current transformer.
• REM plug and resistance substitution box.
• Bipolar footswitch.
• Monopolar footswitch.
• Short test cables less than 61 cm / 24 in. with banana plugs.

Facility-policy-dependent equipment may include:

• Electrical safety analyzer.
• Ground resistance tester.
• Facility-approved ESU analyzer, if used instead of the discrete manual test setup.

Step-by-Step PM Procedure

1. Confirm Device Identification

Action: Verify asset tag, serial number, model, location, and assigned PM interval.

Expected outcome: Device matches the work order and is due for scheduled PM.

2. Inspect Exterior Condition

Action: Inspect the generator housing, front panel, display area, controls, rear panel, vents, labels, and power entry module.

Check for cracked or damaged case, loose or missing hardware, blocked vents, fluid contamination, damaged labels, unreadable markings, evidence of impact, or evidence of overheating.

Expected outcome: Generator is clean, intact, stable, and free of visible damage.

3. Inspect Power Cord and Fuse Area

Action: Inspect the power cord for exposed wires, cracks, frayed insulation, or damaged connectors. Verify the fuse drawer is secure and fuses are correct for the voltage/current rating listed by the manual.

Expected outcome: Power cord and fuse area are safe for use. Damaged cords or incorrect/damaged fuses are corrected before returning the unit to service.

4. Inspect Footswitch and Accessory Receptacles

Action: Inspect rear panel footswitch receptacles, front panel bipolar receptacle, monopolar receptacles, and patient return electrode receptacle for damage, obstruction, looseness, or broken pins.

Insert appropriate connectors to verify secure fit where applicable.

Expected outcome: All receptacles are intact, unobstructed, and provide a secure connection.

Remove from service if: A receptacle is damaged, loose, obstructed, or has a broken pin.

5. Inspect Footswitches and Accessory Cords Used for Testing

Action: Inspect bipolar and monopolar footswitches, connectors, and test accessory cords for damage, corrosion, poor fit, or exposed conductors.

Expected outcome: Footswitches and cords used for PM testing are safe and functional.

6. Internal Inspection, If Facility Policy Allows

Action: Power off and unplug the generator. Remove the cover only if this is allowed by facility policy and performed by qualified personnel.

Inspect for loose connectors, damaged boards, cracked components, corrosion, damaged wiring, and signs of overheating.

Reinstall the cover before powered testing.

Expected outcome: Internal connectors are seated and no obvious damage is present.

Remove from service if: Internal damage, corrosion, burned components, or unsafe wiring is found.

7. Power-On Self-Test

Action: Turn on the generator using the front panel power switch.

Verify all visual indicators and displays illuminate, activation tones sound, successful self-test tone occurs, default mode indicators illuminate, each display shows 1 watt, and the REM alarm indicator illuminates red.

Default mode indicators are Standard bipolar, Pure cut, and Fulgurate coag unless the default coag mode was changed.

The manual warns to use the generator only if the self-test completes as described.

Expected outcome: Self-test passes with no system alarm.

Remove from service if: Self-test fails, an alarm number appears, or the generator is disabled.

8. Verify REM Function

Action: Using a REM plug and resistance substitution box, verify the REM indicator and alarm response.

• Set resistance to 120 Ω; verify REM indicator illuminates green.
• Slowly increase resistance; verify REM alarm sounds at 135 ± 5 Ω.
• Decrease to 60 Ω; verify REM indicator illuminates green.
• Increase to 100 Ω; verify REM alarm sounds.
• Decrease to 30 Ω; verify REM indicator illuminates green.
• Decrease to 10 Ω; verify REM indicator illuminates green.
• Decrease to 3 Ω; verify REM alarm sounds.
• Switch to connector without pin and increase from 3 Ω to 24 Ω; verify REM alarm sounds.

Expected outcome: REM indicator and alarm respond as listed.

Remove from service if: REM does not alarm or clear correctly.

9. Confirm Bipolar Output

Action: Use short test cables, current transformer, true RMS voltmeter, 100 Ω noninductive resistor, and bipolar footswitch.

Connect the test setup to the bipolar instrument receptacle. Set bipolar output to 10 W. Test Precise, Standard, and Macro modes. Record output current for each mode.

Expected outcome: Each bipolar mode measures 316 ± 17 mA rms.

Remove from service if: Output remains outside tolerance after appropriate calibration/service action.

10. Confirm Monopolar Cut Output

Action: Use short test cables, current transformer, true RMS voltmeter, 300 Ω noninductive resistor, and monopolar footswitch.

Connect the test setup to Monopolar 1/CEM and patient return electrode connections per manual test setup. Set cut output to 80 W. Test Pure, Low, and Blend cut modes. Record output current for each mode.

Expected outcome: Each cut mode measures 516 ± 37 mA rms.

Remove from service if: Output remains outside tolerance after appropriate calibration/service action.

11. Confirm Monopolar Coag Output

Action: Use short test cables, current transformer, true RMS voltmeter, 500 Ω noninductive resistor, and monopolar footswitch.

Set coag output to 80 W. Test Desiccate, Fulgurate, LCF Fulgurate, and Spray. Record output current for each mode.

Expected outcome: Each coag mode measures 400 ± 28 mA rms.

Remove from service if: Output remains outside tolerance after appropriate calibration/service action.

Electrical Safety Testing

Low-Frequency Leakage Current

The manual lists specific low-frequency leakage checks.

Output Receptacles and REM Source Current

Action: Measure between all output receptacles, including the patient return electrode receptacle, and earth ground.

Expected outcome:

• Normal condition, ground closed, normal polarity: < 10 µA.
• Single fault, ground open: ≤ 50 µA.

Chassis / Earth Leakage

Action: Measure between chassis and earth ground.

Expected outcome:

• Normal condition, ground closed, normal polarity: < 100 µA.
• Single fault, ground open: ≤ 300 µA.

Output Receptacles and REM Sink Current

Action: Measure sink current using the IEC leakage load and 120 kΩ connection to mains voltage as described by the manual.

Expected outcome: Sink current is ≤ 20 µA.

Ground Resistance

Ground resistance measured in ohms, expected ≤ 0.5 Ω or facility/NFPA 99 criteria if different.

Result =

The manual tells the user to check ground resistance before returning the generator to clinical use, but the provided section does not list a specific ground resistance value. Use facility/NFPA 99 criteria if different.

Touch / Chassis Leakage Documentation

Touch/chassis leakage measured in microamps:

Facility limit used =

Result =

Pass / Fail =

For this device, the manual-listed chassis/earth leakage limits above should be documented when that test method is used.

High-Frequency RF Leakage Current

Monopolar RF Leakage

Action: Using a 200 Ω, 250 W noninductive load, current transformer, true RMS voltmeter, monopolar footswitch, and leakage table if used, activate each monopolar mode at maximum control setting. Record RF leakage current.

Expected outcome: Monopolar high-frequency leakage should not exceed 150 mA for any mode when using the leakage table.

Bipolar RF Leakage

Action: Using a 200 Ω, 250 W noninductive load, current transformer, true RMS voltmeter, and bipolar footswitch, activate each bipolar mode at maximum control setting. Record RF leakage current.

Expected outcome: Bipolar high-frequency leakage should not exceed 60 mA for any mode using either the leakage table or short-lead configuration.

Pass / Fail Criteria

PM Pass Criteria

Pass the PM if:

• Exterior inspection passes.
• Power cord and fuse area pass inspection.
• Receptacles are intact and secure.
• Self-test completes successfully.
• REM function passes.
• Bipolar output is 316 ± 17 mA rms.
• Monopolar cut output is 516 ± 37 mA rms.
• Monopolar coag output is 400 ± 28 mA rms.
• Low-frequency leakage current passes manual-listed limits.
• High-frequency RF leakage passes manual-listed limits.
• Ground resistance passes facility/NFPA 99 criteria.

Remove From Service Criteria

Remove from service if:

• Self-test fails.
• Alarm number appears and cannot be cleared by approved service action.
• REM function fails.
• Output is outside tolerance after calibration/service action.
• Leakage current exceeds manual-listed limits.
• RF leakage exceeds manual-listed limits.
• Ground resistance fails facility criteria.
• Receptacle, cord, housing, or internal inspection reveals unsafe damage.
• Evidence of fluid intrusion, overheating, corrosion, or damaged wiring is found.

Use the manufacturer service manual, facility policy, and approved AEM program to determine the final PM interval and return-to-service requirements.