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My DC neutral polar relay didn't work.

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My DC neutral polar relay didn't work.

Unread postby Richard Pike » Thu Sep 15, 2016 9:14 am

I've had a DC neutral polar relay tucked away my stores for some years. It was on the shelf in Cambridge S&T stores and looked in near perfect condition. ( I bought pretty much everything they had via Collectors Corner in the late 80's) I found a little job for it in conjunction with my Westinghouse hand generator and 4 points in my Soham simulation. As i say it's been tucked away awaiting it's day but i found the neutral armature had seized. There was no choice but to disassemble the case and see what was up. I undid the four screws i was expecting but found a fifth underneath. Anyway on the test bench it worked ok. I plumbed it into the point motor circuit and wound away on the generator to no avail. Out with the meter and the diagnosis was the DC armature had seized. It was taken apart again and it worked fine. It turns out the fifth screw is a transit screw. Take it out and throw it away. Everything is hunky dorie now. My first encounter with a NEW DC polar relay.
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Re: My DC neutral polar relay didn't work.

Unread postby MRFS » Thu Sep 15, 2016 2:52 pm

ND: Why is there a door handle on the inside of my airing cupboard?
MF: Because it's the fire exit from Narnia.

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Re: My DC neutral polar relay didn't work.

Unread postby tjc » Thu Sep 15, 2016 8:35 pm

Our DC style F3 relays come out with a transit screw as well - though I only realised this the first time I had to change one...
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