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Old 12th Feb 2018, 11:57 am   #10
russell_w_b
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Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
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Default Re: How were annunciator panels signwritten?

Quote:
Originally Posted by Bookman View Post
Incidentally, one of the reasons you may still have disc operated relays could be due to the transfer of designs from electro magnetic to static (CDG to MCGG).
Interesting reply, Bookman.

But no... One of the reasons we still employ disc-operated relays is that they're in a clean environment, they still work, and are still maintained and accurate within their specification. It would cost money to replace them. As well as the older AEI PBO2 type we have the later GEC CDG spinning-disc units, which were the last we used before commissioning MCGG relays, of which we have an entire switchboard-full. Never had a problem with the MCGG sets.

I understand (and can appreciate from the handbook and commissioning notes) that the MiCOM series relays arrive from the factory in a default condition, given their flexibility, and ALL parameters MUST be checked through and set for the task-in-hand. There was an incident in the midlands a little while back where incorrect setting of a MiCOM relay caused unintended actions leading to a major power outage; the settings had remained 'masked' until a subsidiary action had caused it to be deployed.

However... I think we're drifting off-topic here: I suspect the OP is maybe not so keen of installing a power-board overload annunciator in his back-kitchen!
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