Author Topic: Capacitors / diodes or not?  (Read 624 times)

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Offline John Candy

Capacitors / diodes or not?
« on: March 29, 2017, 12:03:06 PM »

Building the Monkton Priors control panel involves a digital controller to directly feed signals to the servos operating the turnouts and signals and the "box" for that is protected in itself against overloads/surges.
For the illuminated track diagram panel the LEDs are to be fed at a regulated 5V (from a 12V battery supply) and there are miniature relays (with 5V coils - Axicom type IM23TS) involved in the LED circuits.  Relay specs. state "High surge capability (1.2/50 ?s and 10 / 700 ?s) meets Telcordia GR 1089, FCC Part 68 and ITU-T K20,21,45.
• 1500V between open contacts and 2500V between coil and contacts"

The LEDs themselves are rated at 12V but will be fed with just 5V (via the relays), so would you fit capacitors to the circuits to protect against arcing/flash loads? Would you fit diodes to protect against reverse current? Would this be a bit too "belt and braces"....I want to keep as simple as possible?

John.
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline cabbage

Re: Capacitors / diodes or not?
« Reply #1 on: March 29, 2017, 12:26:05 PM »
The answer is no capacitors and no diodes.

Regards

Ralph

Offline John Candy

Re: Capacitors / diodes or not?
« Reply #2 on: March 29, 2017, 01:07:03 PM »
Thanks Ralph.
My fellow Members, ask not what your Society can do for you, ask what you can do for your Society.

Offline Gavin_B

Re: Capacitors / diodes or not?
« Reply #3 on: March 30, 2017, 07:35:22 PM »
I think keep it simple