BigMike

Thanks.

I do understand why they are used and my reasoning was two-fold (which could be totally wrong).

- How many kits come with relays that do not have diodes? Answer - probably 99% plus.

- I found a thread on the interwebz from a guy that build something similar. The one that he built was probably better quality than what SPOD sells and he knew electronics. I emailed him about not using the diodes and he gave me an explanation that made a lot of sense. But he did use diodes on two circuits for some lights that were powered by high-beams but he ran them inline on the circuit.

The diodes won't hurt anything if installed but they can always be added for sensitive circuits. You can even buy SPST and SPDT relays with the diode already installed in them. I'm just powering LED floods on the windshield and a CB at this point. The LED's are from Black Box and they came with a very heavy duty wiring harness, relay, and switch. The relay didn't have a diode. I didn't use the harness but I did cut it up to run the wires for the lights and attach it my panel since each wire loom was enclosed.

Mark Doiron

The diodes on the relay coils actually protect only what is attached to the coil wiring--in your case I expect just the switch to activate the circuit. They provide no protection to lights, radios, whatever is powered through the switched contacts of the relay. So, unless the circuit uses some type of voltage sensitive switching instead of s discrete hardware switch, I agree the diodes aren't needed.

jnabird333

This turned out really nice! Nice find on the box.

If the run-down protection is something you really liked you can still add it. Here are two options. I'm sure there are more, but I stopped looking after I found these.

30A for $50
"NEW" 12 Volt 30 Amp Low Voltage Disconnect

200A for $125
Cole Hersee Sure Start Auto Low Voltage Disconnect 1 Each Cole Hersee - SureStart™ Automatic Low Voltage Disconnect Switch [CH-48510] - $125.41 : TheElectricalDepot.com!, Electrical Connectors and Much More!

jnabird333

It depends on where the diode is put. If it is put across the coil then you are only managing the relay coil decompression. When we spoke he was thinking of adding the diode across the load terminals which would manage the load's decompression. This can be important with large or noisy 12v loads.

In my case; I use a diode and capacitor to stop relay chatter and protect the CANBUS while using "Hot" that is sourced from a CANBUS circuit. (The factory high-beams and the reverse)

None-the-less we agree he doesn't need them for this application.

BigMike

Nice find! My only worry on the run down is some jackass turning on my LED lights when my Jeep is parked with the top down. I'll probably pass on it for now.

As you can see, when you start making your own relay box, the cost adds up. The SPOD price give you a lot for $435 if you compare apples to apples.

jnabird333

This was a point I tried to make in the write-up I did. Many feel the price of the SPOD is unfair, but it really isn't. If you build in all the features they have, you will likely get close to the same cost in materials alone. This said, it can be a fun project and allows you to add or remove any features you want.