Dip control 400 V MCC
Dip control 400 V MCC
(OP)
We have a dip control panel in our 400v MCCs which I have never come across before. It consists quite basically of two Rhomberg slimline voltages relays set to detect a percentage over or under voltage. Occasionally they react and we have a system shut down. It is never clear whether there was any real problem or not and I am not convinced that this dip control has any positive advantage at all.
I have attached a line diagram.
Perhaps somebody can offer any comment for or against this so called protection.
I have attached a line diagram.
Perhaps somebody can offer any comment for or against this so called protection.





RE: Dip control 400 V MCC
You can play with settings and time delays if any. Unless this MCC is controlling something special that requires shutdown on OV/UV, I would get rid of it or at least disable it for a while and see what happens. Or wire it alarm only.
If at all important have OV/UV and single phasing protection at individual motor controllers/starters and not at MCC main.
By the way what is "dip control"? Something that protects against voltage "dips"? or a name of a process?
Rafiq Bulsara
http://www.srengineersct.com
RE: Dip control 400 V MCC
Most UV/OV protection schemes entail a time delay of some sort to avoid nuisance tripping. A more modern Digital Protection Relay would also provide you with some additional threshold levels at which you could send an alarm to a SCADA system rather and maybe execute an orderly shutdown or a load shed rather than suffer a complete shutdown. It may be time to upgrade...
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RE: Dip control 400 V MCC