I have a K machine level detect module on which the line clamp intermittently will not energize.

The problem follows the module.

The problem seems to get worse the longer the machine has beeen running.

I have a spare LD board but no spare solenoid.

Is there some place I can check for voltage to see if the problem is the board or the solenoid?

Thanks.

It looks like it was the LP450 board. When the line clamp was functioning normally, voltage to the solenoid was 24 VDC. When the machine alarmed, the voltage dropped to 0. When the line clamp failed to energize, the voltage was at 0 when it should have been 24 VDC.

I hope I am right.

I'll take a crack at this until someone who knows can help you. I never had that problem, but if (big IF) my memory is working, you've got it backwards.

I think the function is like this:
24v activates solenoid to open clamp,
0v in alarm state removes solenoid openning it and the normal mecahnical state is to close the clamp.

IF I'm right, I'd start looking for some mechanical obstruction-foreign objects, corrosion of a shaft, etc.

I hope this was some help. I'll go tear one down if a machine is available. (I don't get to keep spare modules.)

I don't think I stated this clearly.

The line clamp was closed when it should have been open.

It was not getting the 24 VDC to make it open.

I changed the LP450 board on the level detect module. The line clamp works fine now.

In seven years of working on Fresenius machines, this is the first time I have seen this problem.

I've never had that one either. Thanks for letting us know what you found for when it does happen to us.