Troubleshoot for Model 655 Gatan Dry Pumping Station

Problem: The “MDP Status light” does not turn green after 5 minutes of use. The turbo pump won’t get up to speed (27,000rpm), there may be a problem with the vacuum being generated. The turbo pump is unable to reach full speed at atmospheric pressure.

Solution: Check that the specimen holder is not leaking. Check that V1 and V2 valves are not leaking.

Make sure that the dry (or roughing) pump is switched on.

Open V2 and close V1 and reattach the cold cathode gauge. Watch for needle deflection on the gauge on the front of the pumping station.

You can swap the turbo pumps between units. If the turbo pump runs well in another station and the light turns green indicating full running speed, the problem is in the original station.

Dry pump troubleshooting: Disconnected power supply from turbo pump, this is the electrical cord at the base of the unit. The dry pump can be run by itself.

Make sure that the specimen holder tee is attached. V1 should be open and V2 closed. Watch for needle deflection on the vacuum gauge. If there is no deflection, the dry pump may need to be serviced. A diaphragm replacement kit should be ordered from Gatan; instructions on how to replace the diaphragms is located in the pumping station manual.

Routine Maintenance: Dry Pump The dry pump uses a diaphragm system to operate. These diaphragms need to be replaced about every 4,000 hours of running time, which can be viewed on the front of the dry pumping station on a small timer reading “HOURS”. The instructions on how to do so are found in the gatan dry pumping station manual.

Turbo pump The turbo pump uses ball bearings which need to be changed about every 30,000 hours of running time. They also need to be lubricated about every 10,000 hours. Thus, there should be two lubrications followed by a ball bearing change per every 30,000 hours. The instructions on how to lubricate the unit can be found in the gatan dry pumping station manual.