N Gauge Forum

General Category => General Discussion => Topic started by: Geoff on October 17, 2014, 06:34:46 PM

Title: Circuit Breakers
Post by: Geoff on October 17, 2014, 06:34:46 PM
I have just found these and they look really handy.

http://www.microminiatures.co.uk/acatalog/Circuit-Breakers.html (http://www.microminiatures.co.uk/acatalog/Circuit-Breakers.html)
Title: Re: Circuit Breakers
Post by: edwin_m on October 17, 2014, 08:17:58 PM
I'd be very cautious about these - just googled and found this page and the trip time of the little blue ones is around 30 seconds, by which time anything they are supposed to be protecting will probably have melted. 

http://uk.farnell.com/multicomp/an-101-fc67200/circuit-breaker-1a/dp/698234 (http://uk.farnell.com/multicomp/an-101-fc67200/circuit-breaker-1a/dp/698234)

There's no part number to google for the other one but it's probably similar, and 3A is too much for N gauge anyway. 

Title: Re: Circuit Breakers
Post by: trainsdownunder on October 17, 2014, 10:25:25 PM
Loking at the data sheet a little more closely the trip time is dependant on overflow current.

The 1 Amp trips within 30 if 100% overload dropping to between 1 & 5 secs with 300% overload. Most decoders have a stall reading of around 2A so I would suggest caution in use to avoid frying those "expensive Chips"

Don't want to go protecting a £2.99 trip with a £25 decoder !

More details on stall currents at https://sites.google.com/site/markgurries/home/decoders/decoder-motor-ratings (https://sites.google.com/site/markgurries/home/decoders/decoder-motor-ratings)
Title: Re: Circuit Breakers
Post by: Malc on October 17, 2014, 10:54:12 PM
I was going to get one for my lights.
Title: Re: Circuit Breakers
Post by: Geoff on October 17, 2014, 11:01:34 PM
Me to Malc I thought they would be handy but not now.
Title: Re: Circuit Breakers
Post by: edwin_m on October 18, 2014, 11:31:05 AM
I doubt any circuit breaker that involves thermal action or mechanical movement (these have both) will be any good at protecting against overloads on DCC.  The cutout on a DCC command station and the circuit breakers designed for DCC power zones are fully solid state and rely on measuring the current, so have a much faster response time. 
Title: Re: Circuit Breakers
Post by: Geoff on October 18, 2014, 03:47:47 PM
Quote from: edwin_m on October 18, 2014, 11:31:05 AM
I doubt any circuit breaker that involves thermal action or mechanical movement (these have both) will be any good at protecting against overloads on DCC.  The cutout on a DCC command station and the circuit breakers designed for DCC power zones are fully solid state and rely on measuring the current, so have a much faster response time.

Thanks Edwin I will probably go down the digitrax route a little expensive but worth it.
Title: Re: Circuit Breakers
Post by: lil chris on October 18, 2014, 09:50:39 PM
Just be carefull of some of the digitrax ones are mecanical ie work with relays, Your are better off with the Dcc specialties psx breakers they are digital.I am using 4 on my layout.
Title: Re: Circuit Breakers
Post by: Geoff on October 18, 2014, 09:52:39 PM
Quote from: lil chris on October 18, 2014, 09:50:39 PM
Just be carefull of some of the digitrax ones are mecanical ie work with relays, Your are better off with the Dcc specialties psx breakers they are digital.I am using 4 on my layout.

Thanks for the heads up on that Chris.