Hey all you tech guys! I just installed an MTH signal bridge using DPDT relays! They work great! The signals activate when a trian is in the block and de-activate when it leaves the block. Only one problem. Now everything else on the isolation block is activating without a train being present in the block???? Its almost like the DPDT relay completed the curcuit to the iso-block. I did wire it up exactly how the instructions read. What gives?
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The 2 outer rails are being connected by the relay coil,maybe 500 ohms resistance, You have to describe your set up more. If you are using AC or DC coils etc. This allows any accessory hooked directly to it to get some voltage through the resistance circuit. This would vary depending on what the accessory is. A solenoid might buzz a bit,a light bulbs might be dim but an LED may light to full brightness. I would recommend all accessories be activated through relay contacts,not directly off the rails. Barring that use a DC circuit and a blocking diode.
Dale H
Thanks, Dale. This is very frustrating! Im using 12v AC DPDT relays from trains electric. Im powering the entire layout using 4 Lionel Powerhouse bricks. The other accessories are connected directly to the outer rail for activation, for example Im using Atlas O 21st Century signal system at the other end of the block to signal trains coming in the opposite direction! It worked great until I installed these relays on the same block. Now they always show stop!
I suspect the Atlas signals use electronic sensing on the track, and it's sensitive enough to see the relay coil as a train on the block. I'd connect the other accessories through the relay you added so they're all activated by the same circuit.
The Atlas O signals are installed using there own curcuit boards. I don't see anyway how I can incorporate a relay in front of that board. Are you suggesting I switch over to DC? And what exactly is a blocking diode? Dont no much about DC operation, its one of the main reasons I model 3Rail!
Thanks,
Jerry
The Atlas signals are connected to the outside rails to sense presence in the controlled block, right? Instead of connecting across the rails, connect them to a NO set of contacts on the relay, you'll get the same result.
Thank you John,
So reguarding the Atlas O signals, instead of connecting the activation wire directly to the outer rail, instead connect this wire to the NO terminal on the said relay?
When I get home tonight I will make these changes and provide an update!
Thanks guys!
If you have an open set of contacts on the relay, just wire the NO and common to the signals in place of the outer rails. If the signal you're using expects the track common to supply power, connect the common rail to the relay contact that is connected to the terminal to the signal that is usually connected to common.
YES IT WORKED!!!!!! Thank you Dale & John!!!!!!
I love it when a plan comes together.
Someone must have said that...