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Old September 11th 03, 12:17 PM posted to uk.transport.london,uk.transport,uk.railway
wanderer wanderer is offline
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First recorded activity at LondonBanter: Jul 2003
Posts: 20
Default A light shines where there was none

On Thu, 11 Sep 2003 09:48:26 +0000 (UTC), Dr Ivan D. Reid wrote:

On 10 Sep 2003 15:31:14 -0700, robsignals
wrote in :
detection relays, connected via 1,200:1 transformer, are rated 1Amp or
5Amp with a wide ranging multiplier, 5A was specified but 1A installed


...


They were carried out but I guess those engineers assumed they had
been handed over correctly installed equipment and never thought to
check the relay rating, pity they aren't brightly colour coded.


Given that there appear to be only two different ratings, an obvious
question is, "Why not?"


The multipliers are usually small tapered plugs that bridge across a
tapered socket, and are hidden away inside the body of the relay, which
may itself be quite small. I don't think colour coding would have
helped, given that the reported procedure for checking the relay covered
both time and current settings, and had apparently been followed without
the wrong setting being noticed. The underlying reason could have been
as simple as a fitter bringing a mug of tea to the engineer at the time
he was checking the settings, causing him to lose concentration for
second, and.....