FAQ: Installing LEDs in McCain PV..

This area is for the discussion of the SignalWiki project.

Moderator: LarryC39

Forum rules
The SignalWiki project pages can be found HERE (wiki.signaltraffic.com).

FAQ: Installing LEDs in McCain PV..

Postby coyttl on Mon Mar 05, 2012 11:27 am

I honestly don't know if this goes here, but a tip for current and future owners of a McCain (ex-3M) PV signal, Mods, feel free to move this, as I'm sure you would anyways.. :grin:

Installing a LED bulb in a McCain Signal requires a small wiring change to the signal - notably, cutting out the dimmer from the circuit. The dimmer cannot handle the LED bulb and will cause the LED to flicker and strobe, and after some time the dimmer will die completely.

Luckily, McCain thought of this, and made it rather simple to install a LED bulb -

  1. Open up the back cover, and locate the wiring going into the front section. You will three three different wire connectors:
    1. A white, rectangular two-prong plug with white and black wires.
    2. Two single-circuit green connectors.
  2. With power off to the signal (duh), disconnect the two green connectors, leaving the white one connected. You will have four separated black wires with green connectors on them. (A wire-tie may be in the way.)
  3. Two of the four black wires will be leading back under the lightbulb socket, and two will lead to wires running back in the front section.
  4. Connect the ends of the wires leading to the socket together. The green connectors should mate fully.
That's it. The circuit's wired so that full power is delivered back to the resistor via the white plug, and then soldered to the two wires leading up to the dimmer. The dimmer, normally, will create a closed circuit, bypassing the resistor. When light sensing falls, the dimmer will open the circuit, causing the feed to be forced through the 35W 550 ohm resistor to the bulb. Depending on light sensitivity, the dimmer will 'pulse' the circuit - opening and closing it at various frequencies - causing the bulb to be powered by full and then resisted feed, allowing the bulb to be 'dimmed'. By connecting the two green connectors together, you're bypassing the dimmer altogether, giving the bulb full power. (The original 3M dimmer may operate the same way - however, I cannot verify that at this point...)

--Mike.
- Fox
"Oh my god there's a bear in my oatmeal!"
User avatar
coyttl
Crusty Old Salt
Crusty Old Salt
 
Posts: 2586
Joined: Sun Feb 20, 2011 1:12 pm
Location: Harpers Ferry, WV

Re: FAQ: Installing LEDs in McCain PV..

Postby Crunge98 on Mon Mar 05, 2012 11:33 am

Good info :thumbsup:
Jay J------




A house is just a place to keep your stuff while you go out and get more stuff.



Click Here!
User avatar
Crunge98
Crusty Old Salt
Crusty Old Salt
 
Posts: 8484
Joined: Sun Jul 01, 2007 10:20 am
Location: New Philadelphia, Ohio. Headquarters for OSM

Re: FAQ: Installing LEDs in McCain PV..

Postby 2070 on Mon Mar 05, 2012 4:53 pm

With ANY LED bulb, No dimmer can be used with a traffic signal LED.

You can not "DIM" them through the Load Switch either!!!!

They are made to run on 120 volts AC @ 60 Cycles..... :blink:
Well what do you know. If I put my name here, I do not have to sign it everytime.

Phil
:doh:
Used Traffic Signal Equipment Expeditor
http://www.twingreenonline.com/
https://www.facebook.com/Twin.Green.Traffic.Signal
https://www.facebook.com/Traffic.Light.King
User avatar
2070
Crusty Old Salt
Crusty Old Salt
 
Posts: 9975
Joined: Tue Sep 02, 2008 8:29 pm
Location: Columbia County, New York


Return to Wiki Topics

Who is online

Users browsing this forum: SignalFreak and 0 guests