Back-Up Light Question

[4x4junkie]

^^
You could do your setup with one relay.
You'd still need two diodes, though they would only need to be small 1-amp diodes.

I tend to agree though the need for a relay isn't quite as great with the lower current draw of LED lights.

 

[anickode]

^^
You could do your setup with one relay.
You'd still need two diodes, though they would only need to be small 1-amp diodes.

I tend to agree though the need for a relay isn't quite as great with the lower current draw of LED lights.

Yes, I could use diodes to trigger a single relay. I was just pointing out that to use JUST relays would be overly complicated for a few amps worth of LED lights.

 

[hamr26]

I have used the Rigid clone flush mount lights and used the Rigid up/down angled adapters. Giant amount of light from such a small package. I would definitely include a way to not use the lights EVERY time you reverse since they are so bright (thinking of urban situations).

 

[carbon60]

If one wants to avoid the "flash" that happens when shifting some automatic transmissions past R on the way from P to D, is there a solution?

I ask because a good friend of mine, who I often end up driving behind on the trail, flashes a rather large LED bar _everytime_ he puts the rig into gear.

 

[4x4junkie]

^^
He probably should put a switch on that so he can shut them off. The 3-way switch setup mentioned earlier in the thread works very well in situations like that.

But to answer the question, a way to add a delay would be to put a resistor inline with the wire going to the coil of the light's relay, and then put a large capacitor across the relay coil itself. The time-constant of the circuit created by the resistor & capacitor will prevent the relay from energizing for a brief moment (values to start with might be 24-27 ohms for the resistor, and 22,000µF (22mF) for the capacitor. This should provide roughly a 1 second delay (typical automotive lighting relays click in at about 7-9 volts). Adjust the size of the capacitor accordingly if a longer or shorter delay is desired).

Note that this will also create a similar delay while shutting it off too.

 

[carbon60]

But to answer the question, a way to add a delay would be to put a resistor inline with the wire going to the coil of the light's relay, and then put a large capacitor across the relay coil itself. The time-constant of the circuit created by the resistor & capacitor will prevent the relay from energizing for a brief moment (values to start with might be 24-27 ohms for the resistor, and 22,000µF (22mF) for the capacitor. This should provide roughly a 1 second delay (typical automotive lighting relays click in at about 7-9 volts). Adjust the size of the capacitor accordingly if a longer or shorter delay is desired).

Makes sense. I'll harass him into doing that.

Also, if you want a switch in the cab and another in the cargo area to be able to use the lights as camp lites, how would that be wired?

 

[emtmark]

FWIW I'm following this closely and getting ideas how to streamline my own plans. Thank you all for contributing. I am sure I will have questions soon. I'm planning on building a mock up before install to test everything out.



Sent from my iPhone using Tapatalk

 

[patoz]

Also, if you want a switch in the cab and another in the cargo area to be able to use the lights as camp lites, how would that be wired?

This is just a simple circuit for household wiring, but the principle is the same, just substitute the words "Ground' for 'Neutral', and 'Positive' for 'Live'. This is the circuit that would be used for a light in a stairwell, where you had a switch at the bottom and one at the top.

With the lights grounded to the body or frame, it requires two control wires to the rear (Common 1 and Common 2), and two SPDT Switches (one in the front and one in the rear). The switches will not have specific 'On and Off' positions, because each one will be relative to the position of the other one. If you are powering the lights via relays, then just use this circuit to control the relays.