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Insulated Joint Tester

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Insulated Joint Tester

Unread postby Mad Mac » Sat Feb 20, 2010 5:58 pm

Anyone got any experience of these? Looking for info on what is considered "good" in terms of resistance when measured with one.
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Re: Insulated Joint Tester

Unread postby John Webb » Sat Feb 20, 2010 7:55 pm

Are we talking about an insulated joint in a cable or in the track, as in separating track crcuits from each other?
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Re: Insulated Joint Tester

Unread postby Mad Mac » Sun Feb 21, 2010 3:30 am

In the track, Sir.
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Re: Insulated Joint Tester

Unread postby John Webb » Sun Feb 21, 2010 1:28 pm

Thanks - I could easily cope with the former having had much experience in that area.

I freely admit to having only some theoretical knowledge of track circuits, but as someone used to handling electrical instruments, I would have thought that the insulation between adjacent track circuits should be at least 10 times that of each track circuit in order that the relays etc in each track circuit are not shunted by the adjacent track circuit sufficiently to cause misoperation. But I will happily be corrected on that score!
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Re: Insulated Joint Tester

Unread postby trackman » Sun Feb 28, 2010 4:51 pm

You want a reading that is twice the resistance of the rail to the ballast. A clean, dry perfectly assembled insulated joint has, in theory, an infinite resistance, so all that leaves is the electrical path via the sleepers and ballast.
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