Testing electromechanical relays - Voltage requested to the current am
Testing electromechanical relays - Voltage requested to the current am
(OP)
What is the voltage we still require today at a test set (current output) for being able to test the most difficult electromechanical relay?
I am out of mechanical relays since years, but in the US there are a lot of them.
Do you have please some data in terms of VA, or max voltage requested to the current amplifiers?
Any real data from the field?
Thanks for any input!
I am out of mechanical relays since years, but in the US there are a lot of them.
Do you have please some data in terms of VA, or max voltage requested to the current amplifiers?
Any real data from the field?
Thanks for any input!






RE: Testing electromechanical relays - Voltage requested to the current am
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Testing electromechanical relays - Voltage requested to the current am
Do you need the power consumption of the test set or the output parameters? For example a typical test set might be able to supply 150V AC and 50A but not at the same time. This would cover most relays
RE: Testing electromechanical relays - Voltage requested to the current am
yes, I was talking about protective relays. Sorry..
150 VAC?
So much?
I have hard to believe that a protection relay must be energized with 150 V AC (RMS I understand), on the current circuit. But I may be wrong.
I have the feeling that 80 V AC RMS if not 40 V AC are enough, but unfortunately i´this is just a feeling for the moment.
If you have some electromechanical protection relay in your substations (probably those with the rotating disc), please try to remember me and verify what is the voltage that is applied to the rely when you test it.
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
I am talking about CURRENT INJECTION.
What I have in mind is a directional earth-fault relay, because some colleagues state that they need more than 100 V RMS in the current circuit in order to test it. But they never told me the relay type.. and never showed me the relay, so I believe the troubles are somewhere else.
RE: Testing electromechanical relays - Voltage requested to the current am
Relay instruction books are available on-line from ABB for the CO-x series of overcurrent relays and from GE for the IAC and IFC series.
It can be done with a good, high-power audio amplifier in some cases.
You could just check the specs on relay test sets. Any of them sold in the US should be adequate to drive common electro-mechanical relays.
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
Current amplifiers with 40 V rms are much less expensive than current amplifier that manage a voltage of 150 V rms, and I am not sure I want to really spend those money..
Putting in series current amplifiers (to increase the total voltage) is not the best idea.
To my opinion, 40 volts RMS are more than enough for most of the electromechanical relays, but some colleagues are here talking about 150 V rms, and this figure popped also up even in this thread.
Has anybody really SEEN 150 volts RMS applied on the current circuit of the electromechanical relay?
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
htt
RE: Testing electromechanical relays - Voltage requested to the current am
Some electromechanical relays can be rather difficult to test with the newer solid-state test sets.
old field guy
RE: Testing electromechanical relays - Voltage requested to the current am
Hope it helps.
capuchi
RE: Testing electromechanical relays - Voltage requested to the current am
RE: Testing electromechanical relays - Voltage requested to the current am
The fact that some test sets are shooting such big output values, does not always mean they are doing right. A lot of things in our world have been done because "it has always been done like that", or just because some competitors have done it.
To my opinion, people are trying to test relays connected in series from the end of the series, and for this you might need high compliance voltage (the sum of all relays in series). This test would be a wrong test, because first you should perform a relay test, independent from the system in which it is going
o work, then you can perform a system test, to verify all the connections, but you do not need to test again the relay itself, You may just need to inject a higher fault current, not requiring such high voltage.
That's what I am trying to discover.