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Modern LED signal heads

Discussion in 'Signalling M.I.C.' started by The Green Howards, Jul 21, 2024.

  1. The Green Howards

    The Green Howards Nat Pres stalwart

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    I've been given a modern signal head by a friend who would like me to make it work as a display piece: it's a Unipart-Dorman "iLS" single lens three-aspect head, designed to run from 110VAC according to the plate on the back. It has an attached cable with a large 13-pin plug on it.

    Does anyone know anything about these? Looking at their website, the low current draw (70mA) suggests that it might be one that proves it is functioning to the signal box by relay closures.

    So far I have separated the electronics from the body but I can see the PCB carrying the LEDs (I was also surprised to see they're only 5mm ones) needs to be separated by desoldering the wires to the electronics.

    Any help gratefully received - I'd rather not have to reverse-engineer it!
     
  2. Martin Adalar

    Martin Adalar New Member

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    These Dormans are plug and play and are fed via a plug coupler and are driven from a signal module in the nearby loc. as opposed to a rack of relays in said loc cupboard. Therefore you do not have to reverse engineer anything in the light module itself.
     
  3. Selsig

    Selsig Member

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    Not exclusively - Dorman iLS heads can be driven from either SSI modules or relay interlocking. You'd need a 110v feed for each aspect, and an ECR, Q style / BR 930 spec, of a pin code I can't recall off hand at 2am in a hotel in Newcastle, but I will endeavour to look at some diagrams as soon as possible. Stupid thing is I've just got back in from testing one, but tired brains are forgetful.

    John
     
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  4. The Green Howards

    The Green Howards Nat Pres stalwart

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    Hi John,

    anything that you can help with will be gratefully received - it may actually be faulty but I won't know until I can test it, of course. I have plenty of small 50VA 240/110V autotransformers here to provide a supply. My initial guess was that it would have a single or preferably redundant 110V supply and relay closures would provide the aspect switching but that doesn't allow for a relay failure to switch it to danger.
     
  5. Selsig

    Selsig Member

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    It won't need anything more than 110v applied to the correct cores to prove whether it's working or not - I can provide a typical wiring diagram for the aspect control circuitry pretty easily, if you want to run it over relays, but it isn't a necessity to test the head. You can light all three aspects at once if you feel so inclined, without harm, it just looks a bit odd!

    John
     
  6. The Green Howards

    The Green Howards Nat Pres stalwart

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    That would be greatly appreciated - I'll PM you my e-mail address.
     
  7. Selsig

    Selsig Member

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    Some stuff sent your way

    John
     
  8. The Green Howards

    The Green Howards Nat Pres stalwart

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    Info received - that's fantastic, thank you so much for your help. Once I've tested it, I can have a go at designing something to drive the head in sequence R - Y - G - R.
     

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