Smiths Medical Medfusion 4000

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Manual Reference

Medfusion Syringe Infusion Pump Model 4000 Series Technical Service Manual

Manufacturer Recommendation / AEM Status

Manufacturer-Listed PM Items

The manufacturer-listed scheduled maintenance includes cleaning and disinfecting the pump before maintenance, general inspection, power-up test, sensor calibration value verification, plunger travel test, motor drive and occlusion operational test, flow delivery accuracy test, AC line leakage test, battery status review, next PM date update, and LAN/wireless setting review when applicable to facility workflow.

Sensor verification includes the force sensor, small syringe size and position sensor, and large syringe size and position sensor.

Manufacturer-Listed Frequencies

Mandatory annual maintenance testing is listed annually. Additional testing is required whenever the pump has been damaged or dropped. If the pump is predominantly battery powered, preventive maintenance is recommended every 6 months.

Battery replacement is required when full capacity is less than 3024 mAh or charge cycles exceed 400. Test syringes are to be changed at least monthly because syringe lubrication evaporates. When recharge is needed after PM or check-out, leave the pump connected to AC power for at least 8 hours.

Manufacturer-Listed Part Numbers / Materials

Silicone grease: Grease, Silicone, 111 Compound, Smiths Medical part number 0382000000.

Battery: Replace only with Smiths Medical original/specified battery pack.

The calibration kit is referenced in the manual’s calibration and repair parts list.

Post-Repair Safety Inspection Requirements

The manual repeatedly directs verification of pump function after parts replacement or service. After repair, replacement, battery replacement, calibration, or opening the pump housing, perform applicable functional verification before returning the pump to service.

AEM Status

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

This procedure covers visual and mechanical inspection, power-up and indicator verification, sensor calibration verification, plunger travel and occlusion operation, flow delivery accuracy, AC line leakage testing, battery condition review, PM date reset, and CMMS documentation.

Required Tools and Equipment

Medfusion Model 4000 calibration kit
Small calibration slug
Large calibration slug
Force gauge
New 50 mL or 60 mL Luer-lock syringe
3-way stopcock
Electrical safety analyzer
Calipers with 0.001 inch resolution
Approved cleaning/disinfecting materials
Silicone grease, Smiths Medical part number 0382000000, if needed
Facility CMMS/work order documentation system

Facility-policy-dependent equipment may include network access or PharmGuard workflow access if LAN/wireless verification is part of facility PM, plus any additional electrical safety documentation requirements.

Step-by-Step PM Procedure

1. Clean and prepare the pump

Action: Turn the pump off, disconnect AC power, and clean/disinfect the pump using approved cleaning agents. Do not immerse the pump, autoclave it, spray fluids into bottom openings, or use prohibited solvents.

Expected outcome: Pump is clean, dry, and safe to handle before PM.

Why it matters: The manual specifically warns to clean the pump thoroughly before maintenance.

2. Perform general inspection

Action: Inspect the pump for cracked housing, torn keypad, damaged labels, loose internal or external parts, damaged tubing guides, damaged force sensor seal, damaged AC receptacle seal, damaged or worn power cord, pole clamp operation and tightness, and power cord retainer installation.

Expected outcome: No physical damage, missing parts, loose parts, or unsafe cord condition.

Remove from service if: Housing is cracked, keypad is torn, power cord is damaged, seals are damaged, internal parts are loose, or any mechanical component cannot operate smoothly.

3. Verify mechanical movement

Action: Check smooth operation of the syringe plunger driver, syringe release lever, syringe flange clip, and syringe barrel clamp. Apply a light layer of Smiths Medical 0382000000 silicone grease to the plunger tube and barrel clamp rod if needed.

Expected outcome: All syringe-loading and plunger-drive components move smoothly without sticking, binding, or looseness.

4. Verify AC connection and indicators

Action: Plug the AC power cord into a 100 to 240 VAC source. Verify the AC indicator and battery charge indicator are lit.

Expected outcome: AC indicator and battery charge indicator function normally.

Remove from service if: AC power connection, AC indicator, or charge indication fails and cannot be corrected.

5. Perform power-up test

Action: Ensure no syringe is loaded and the barrel clamp is fully down. Power the pump on.

Verify two distinct alarm beeps, LED indicators turn on and off except AC and battery indicators, battery capacity is greater than 0%, no self-test failures occur, display is legible, contrast is acceptable, backlight changes from normal to extra-bright and back, and when AC is unplugged the battery indicator flashes and AC indicator turns off within several seconds.

Expected outcome: Pump powers up normally with no self-test failures and proper display/indicator behavior.

Remove from service if: Self-test fails, display is unreadable, alarm beeps fail, indicators fail, or power transition fails.

Record: Hours powered on, hours of operation, and motor shaft rotations.

6. Access Biomed diagnostics

Action: From the Main menu, select Biomed. Enter passcode 2580. Go to Biomed > Diagnostics > Monitor Analog Sensors.

Expected outcome: Force, plunger position, and syringe size values can be viewed.

7. Force sensor check

Action: With no syringe loaded, verify the force reading.

Expected outcome: No syringe loaded force reading is -0.7 to +0.7 lb.

Action: Load the force gauge with the foot positioned toward the head of the plunger driver. Zero the force gauge. Increase force until the gauge reads 15 lb.

Expected outcome: Pump force reading at 15 lb applied is 12.6 to 17.4 lb.

If out of specification: Recalibrate the force sensor and retest.

8. Small syringe size and position sensor check

Action: Load the plunger driver onto the end of the small calibration slug with flippers open and about 0.1 lb applied to the force sensor.

Expected outcome: Position reading is 0.660 to 0.740 in.

Action: Load the small calibration slug into the barrel clamp without loading the plunger driver. Move the barrel clamp head slightly back and forth to find the lowest size reading.

Expected outcome: Small size reading is 0.234 to 0.294 in.

If out of specification: Recalibrate the applicable sensor and retest.

9. Large syringe size and position sensor check

Action: Load the plunger driver onto the end of the large calibration slug with flippers open and about 0.5 lb applied to the force sensor.

Expected outcome: Position reading is 4.660 to 4.740 in.

Action: Load the large calibration slug into the barrel clamp without loading the plunger driver. Move the barrel clamp head slightly back and forth to find the lowest size reading.

Expected outcome: Large size reading is 1.222 to 1.282 in.

If out of specification: Recalibrate the applicable sensor and retest.

10. Plunger travel test

Action: Return to the Main menu. Load an air-filled 50 mL or 60 mL syringe. Select mL/hr mode and set the rate to 20 mL/hr. Clear total infused and start delivery.

Verify the three green infusing indicators sequence right to left, pump runs until at least 0.033 mL has infused, lock indicator turns on when Lock is pressed, and lock indicator turns off when Unlock is pressed.

Action: Change rate to the maximum available rate and allow the unit to drive the full syringe length.

Expected outcome: Syringe Empty alarm displays when the syringe is empty, red alarm indicator lights, and alarm tone quality is acceptable.

Remove from service if: Unexpected alarms, system failures, drive problems, or indicator/audio failures occur.

11. Motor drive and occlusion operational test

Action: Connect a 3-way stopcock to an air-filled 50 mL or 60 mL Luer-lock syringe. Load the syringe on the pump. Select mL/hr mode and set the flow rate to the maximum rate shown.

Prime at least 0.2 mL. Close the stopcock to the syringe. Select Options > Override Occl Limit > High. Start infusion.

Expected outcome: Pump operates until an occlusion alarm occurs. After alarm and motor reverse stop, opening the stopcock releases pressure. Re-closing the stopcock and restarting causes another occlusion alarm. Test can be repeated until the plunger reaches the end of the syringe.

Remove from service if: Any alarm other than occlusion occurs during this test, or if occlusion detection does not operate correctly.

12. Flow delivery accuracy test

Action: Use a new 50 mL or 60 mL syringe from the manufacturer-listed table. Return to Main menu, select mL/hr, select syringe manufacturer, load air-filled syringe, and enter 300 mL/hr.

Set volume limit to 50 mL if configured. If volume limit is not configured, stop manually when TVD reaches 50.0 mL. Prime at least 0.2 mL. Measure from the outside of the syringe flange to the inside of the syringe plunger. Record starting position, ending position, and travel.

Expected travel:

B Braun Perfusor 50 mL: 3.146 to 3.275 in
B Braun Omnifix 50 mL: 3.146 to 3.275 in
BD 60 mL: 3.473 to 3.615 in
Monoject 60 mL: 3.473 to 3.615 in
Terumo 60 mL: 2.901 to 3.020 in

Remove from service if: Flow delivery accuracy travel is outside the manufacturer-listed range.

13. Battery maintenance check

Action: Connect pump to AC power and verify the battery charge indicator is on. Power the pump on and go to Biomed > Diagnostics > Monitor Battery Status. Allow readings to stabilize.

Document: Battery capacity %, full capacity mAh, remaining capacity mAh, voltage mV, current mA, temperature °C, and charge cycles.

Expected outcome: Battery information displays normally, full capacity is 3024 mAh or greater, charge cycles do not exceed 400, and charge current behavior is appropriate for battery state.

Replace battery if: Full capacity is less than 3024 mAh, charge cycles exceed 400, no battery information appears after connection checks, or the battery cannot hold charge or immediately shuts down when AC is removed.

After battery check or PM, leave pump connected to AC power for at least 8 hours if recharge is needed.

14. Set next PM date

Action: Go to Biomed > Utilities > Set/View Next PM Date. Enter the next scheduled PM date per manufacturer-listed interval or approved facility AEM schedule.

Expected outcome: Next PM date is updated and documented.

15. Check LAN/wireless settings, if applicable

Action: If the facility tracks network readiness during PM, verify wired or wireless network status under Biomed > Network Settings.

Expected outcome: Network configuration is appropriate for facility use.

Facility policy note: This is especially important when pumps return from service, because the manual notes configuration/network settings may need to be restored before return to use.

Electrical Safety Testing

The Medfusion Model 4000 is listed as Safety Class II with functional earth, Type CF equipment. The manual states that protection against electric shock does not rely on protective earth grounding. Therefore, it is neither possible nor necessary to perform a ground resistance test.

Ground Resistance

Ground resistance test: Not applicable per manufacturer manual.

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

Result = Not performed / Not applicable per manufacturer manual

AC Line Leakage Test

Action: Connect the AC power cord to the electrical safety analyzer. Set analyzer to line leakage mode. Turn the pump on.

Touch/chassis leakage measured in microamps at plunger driver tube:

Facility limit used =

Manufacturer-listed normal setting limit: Less than 100 µA

Result =

Pass / Fail =

Optional CF Verification Setup

If performed, fill a beaker with 0.9% saline, load syringe and tubing with saline, place saline-filled tubing in contact with saline in the beaker, and place analyzer ground reference in contact with saline.

Patient-applied/CF leakage measured in microamps: