SB5 short circuit

Model Railroader Electronics and DCC
1

I want to praise NCE for their service. I have an SB5 that shorted out on me. I sent it to them and they repaired it and sent it back to me “free of charge”.

Second part of this post is: I would like to know if there is something cheap and simple that I can put between the SB5 and its connection to the track to prevent this in the future? Obviously, I am not an electronics wizard.

Thanks for any help that is offered.

wdcrvr

2

Thanks for the update. NCE are good folks.

How do you currently have your SB5 connected to your track? Are you using a UTP panel?

Tom

3

there is a plug in the front of the sb5 that is used to connect two wires directly from the track or bus wires.

4

So you are connecting your Power Cab to the front panel of the SB5 as well?

I would recommend connecting your SB5 to a UTP panel then plugging your Power Cab to the front panel of the UTP panel. Additional UTP panels can be daisy-chained from the first UTP panel around your layout and this will allow you to be more mobile with your Power Cab. Just a thought…

Tom

5

https://ncedcc.zendesk.com/hc/en-us/articles/360001236273-Circuit-Breaker-for-the-SB5

6

You need a circuit breaker between the SB5 and the tracks

From the NCE zendesk: The SB5 and Power Cab have built in overcurrent sensing for basic self-protection that will continuously try to reset until destroyed if left uncorrected."

If you have a derailment, while you are upstairs fixing an adult beverage, the SB5 is turning on and off until bad juju happens.

The PSX circuit breaker is known to fuction well with NCE

7

Yes I am using utp panels to connect my controllers. Your question was how was I connecting to the track?

8

csx thanks for the info. I just need to know what does wire in series mean. I am great with “wood” not so much with electronics. thanks wdcrvr

9

Yes, the PSX circuit breaker would work but I don’t see $40 as “cheap”. The automotive light bulb sounds like a great idea.

10

Got it. I thought maybe you were using the front panel of your SB5 to make all your connections - i.e track bus to track & cab bus to Power Cab vs utilizing a UTP panel, which I think makes for a cleaner interface.

I guess the cheapest or simplest solution is to not leave your trains running unattended for more than 3 minutes. If you need to leave the room then just stop your locomotives or shut the layout down.

Tom

11

“In series with” just means ‘in line with’. You want the breaker between the SB5 and any ‘short’ in the track, so you ‘cut’ the circuit to the track (the hot side alone would be sufficient) and insert the breaker.

I think this is clear, but I’ll say it anyway: this breaker will not protect the SB5 by shutting off its power. It is ONLY to preclude futile cycling that cumulatively damages the internal components.

You may want a ‘fast-acting’ breaker rather than one that trips on sustained overcurrent. Best will be a type that can be adjusted just ‘inside’ the point where the device itself trips and cycles, to reduce any ‘false tripping’ from transient conditions.