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ztnezzy1998
October 9, 2017, 06:43 AM
We were trying to test the pressure gauges and the the controls at the plc that it was getting power for the alarm and to trip the main. We were just filling the transformer with nitrogen till we saw the alarm and trip at the plc. Question is what does everyone else do to check the calibration on the gauge and to check the alarms at the plc.

SecondGen
October 9, 2017, 10:20 AM
What are the vacuum and pressure pickup settings? What size transformer?

Depending on what you have I would probably do it the same way. Set your pressure alarm down to a couple pounds and your vacuum alarm to zero, add nitrogen to get a pressure alarm, then relieve pressure to trigger the vacuum alarm.

You could also remove the gauge if possible and use fittings to attach your nitrogen tank to the gauge, just don’t forget to use the appropriate plug for temporarily plugging the tank opening where you take out the gauge!

ztnezzy1998
October 9, 2017, 11:32 AM
What are the vacuum and pressure pickup settings? What size transformer?

Depending on what you have I would probably do it the same way. Set your pressure alarm down to a couple pounds and your vacuum alarm to zero, add nitrogen to get a pressure alarm, then relieve pressure to trigger the vacuum alarm.

You could also remove the gauge if possible and use fittings to attach your nitrogen tank to the gauge, just don’t forget to use the appropriate plug for temporarily plugging the tank opening where you take out the gauge!

they were 13200 to 208/120 and we did not have the pickup setting thats what they wanting figured out along with the function of the the pressure gauge and the plc. The reason i asked is to see if there was any other way people would do this because we blew the prd on a few of these transformer.

SecondGen
October 9, 2017, 12:30 PM
they were 13200 to 208/120 and we did not have the pickup setting thats what they wanting figured out along with the function of the the pressure gauge and the plc. The reason i asked is to see if there was any other way people would do this because we blew the prd on a few of these transformer.

The pickups should be set down when performing the test otherwise you could blow the PRD, as you know. In a case like yours, it would be advisable to remove the gauge and hook it up to your nitrogen bottle because it sounds like you need to verify the actual pickup value / gauge calibration as well.

Lowering the pickup value with the gauge installed will only test the contact operation, it will not verify whatever the final settings are supposed to be. So I guess to answer your original question, the procedure depends on whether you are looking to verify only the contact operation, gauge, or both.