Flasher Relay Questions

[SierraHotel]

Being that I am a lowly roofing consultant, and not an electrical engineer (and that I want to quit buying flasher units!), I’ve got some questions/clarifications for Bjorn’s relay modification. I’m sure his sketch is simple and straightforward for someone that has a clue, unfortunately it would appear I do not. I’d rather not buy yet another flasher because I misinterpreted it.

1. Is my sketch correct for the hookup of the relay? Are the A & C wires hooked up to the X1 & X2 posts or the A1 & A2 posts.
2. The relay I bought came with a diode (black with a light blue stripe) between X1 and X2, is this adequate or does the diode need to connect wires A and C after the relay?
3. Can the relay be used for other things such as the headlights and convoy lights concurrently, or is it just one relay for one item.

Enquiring (and frustrated) minds want to know…thanks Bjorn!

 

[cranetruck]

You got it right. Make sure that the diode has its band ("light blue stripe") facing the X1 terminal.

One relay per application, this one is energized only when the flasher module is "on".

BTW, nice drawing.

 

[SierraHotel]

You are the man (as always), Bjorn!

 

[dabtl]

I find it much easier to keep whining for Bjorn to make me just one more. Please? Pretty please?

 

[cranetruck]

Okay, okay, I now have an extra relay, so you'll have it by Christmas, how's that?

 

[dabtl]

Great.

 

[Jakob]

What's the purpose of this mod? It seems like there's an original post somewhere that I should read...

 

[dabtl]

Flashers are subject to rapid failure from electrical surges. The new flashers especially. Bjorn has designed a protective circuit that eliminates the failures from that cause. I put one on my M35 that had blown two flashers rapidly. No more problems.

 

[Blacksmoke]

Is there a link to the original write-up with the specs of the parts? Just replaced my flasher with a brand new one & would rather not have it fried.

 

[cranetruck]

Blacksmoke, access the forum and do a search with "flasher" and "relay" as keywords. You will get a lot of information regarding the turn signal flasher and also the headlight relay fix (to prevent an overload of the light switch circuit breaker). This and more have also been covered in my articles in the Military Vehicles Magazine (see "Resources").

 

[tmallow2004]

I see what you're doing. The flasher is driving the low current coil on the relay instead of the lights directly. The relay contacts take the surge. Can you give me a source and model number for that relay? Or rather, a current rating (DC and pulsed) for the relay contacts? Think I may want to install this setup.

Thanks,

 

[cranetruck]

Look for mil spec relays on ebay (too costly to buy new, for me anyway) with a 28 vdc coil and 10 to 25 amp contacts, they can handle the inrush currents and in case of a short circuit, trip the circuit breaker.
Typically a 25 amp rated mil spec relay can handle a 10 amp "lamp load", which is more than enough for this application.

 

[Jakob]

I'm looking around for the relay, no luck yet.

 

[Blacksmoke]

I work on industrial machinery & most industrial controls now are 24VDC. When we junk out machines I grab a few relays. I already have these relays installed on my truck: brake light switch to give 12V to my trailer brake controller, relay for my dash lights to run a 12V bulb for my pyro since I couldn't find the right bulb in 24V, & I have a relay box at the back of the truck to convert brake, turn, & tail to 12V for my 7 pin RV plug. Sounds like I will be adding a couple more.

 

[jim-m35a2]

Maybe your blinker box oil needs changing.................
________
Honda Orthia