Troubleshooting Prep Station Components and Overflows

Objective: To provide guidance on testing and troubleshooting prep station components

Video: Troubleshooting Prep Station Components (5 minutes)

1. Remove Work Surface

2. Identifying Prep Station Components

There are 3 solenoids used for each prep station

Fluid Solenoid is mounted to the front of the prep station. When the solenoid is activated, it opens the valve and lets fluid into the prep station
Vent Solenoid is mounted on the left and when energized, allows a puff of air to enter and help push the waste fluid away
Vacuum Solenoid is mounted on the Waste Vacuum Manifold. When activated it creates vacuum at prep station
Transducer Used to measure vacuum pressure
Fluid Sense Board is next to the prep stations and relay signals for the Transducer, Vent and fluid solenoids, reed sensor and fluid sensor.

3. Inspect Prep Seal and Latch

Prep Seal - Check the Oval rubber seal for any damage and ensure it is clean and properly installed.
Check the hooks on front of prep station for damage
Check spring latch at back of prep station for proper functionality.

4. Visual Inspection of Fluid Sense board and pan

Inspect the following for proper installation and operation

5. Log in as Technician

6. Navigate to Tech Pane

7. Automated test

Select “test” button on lower right of tech pane
Run Prep Flow A and Prep Flow B Test
Prep Flow test will turn on vacuum, then fluid, and then remove the fluid in the prep station.
Improper flow could be caused by blocked port holes, a clogged prep filter or defective sealed solenoid.
Clean holes with paper clip, and retest, repeat until improvement is shown.

8. Manual Prep flow test

9. Manual Reed Sensor Test

Insert every adapter in each prep station to make sure sensor detects adapter.

Prep A
Prep B
If it fails to detect a specific adapter, check the adapter for damage or missing parts.
If adapter looks good, adjust reed sensor.by removing prep station and adjusting sensor as needed.
If it fails to detect any adapter, after adjusting reed sensor, inspect connections and cables on fluid sense board and where that cable plugs into the I/O board
If problem persists for only one prep station, swap the fluid sense boards and retest.
If both prep stations don’t detect adapter after adjusting reed sensor and testing fluid sense boards, check connections on I/O board and replace if necessary

10. Electrical check of Solenoids

Each Prep Station uses 3 solenoids. It has 2 solenoids attached to it and a third on the waste vacuum manifold.

Unplug each solenoid one at a time and test for resistance (75 Ohms is optimal).
On Waste manifold, check the vacuum solenoids for Prep A and B (75 Ohms is optimal).
If there is a solenoid in question, it is best to take its resistance readings with an Ohmmeter. Disconnect component from board and test each solenoid individually. A good solenoid should read about 75 ohms. If solenoid was recently being used, it may be HOT and the reading may be closer to 95 Ohms. Replace any solenoid out of spec.

11. Testing Vent Valve

Place the HP2 refill adapter on one the prep stations
Turn on Vacuum pump
Open Vacuum valve on prep station with adapter on it
Note the drop in pressure @ the separator. The difference is called the delta. Delta should have a range of 3 -10in/Hg
Less than 3 delta indicates clogged vacuum ports or clogged prep filter
Greater than 10 or a continuous drop of pressure indicates a weak vacuum pump.
Cover the hole at the bottom of the HP2 Refill adapter, the pressure at regulator should increase to max value as well and match the pressure at the prep station. (approx. 15.5 in/Hg)
Opening the vent valve will cause the pressure at the prep station to drop rapidly
Closing the Vent valve should bring the pressure at the station back up.
Test 2-3 times to verify consistent function of the valve.
If resistance of solenoids is ok, but pressure changes do not occur, the valve stem may be at fault. Replace Prep Station assembly.

12. Testing connection to I/O board

If prep station issue still persist after all the above test.
Swap the cable going to the fluid sense board.
If problems stay with prep station, the fluid sense board is the suspected fault
If the problem follows the cable, the I/O board or cable from I/O to fluid sense board is the likely suspect.

13. Verify Operation

Perform automatic prep flow test for A and B
Run cartridges in the prep station and weigh them after to verify acceptable weight.