Wiring Two LED Work Lights

[bluedunn]

Hi-

Can someone tell me how I would go about wiring together two LED work lights such that they can be turned on by one switch?

Is it as simple as tapping into the positive wire of light A to the positive of light B and the negative of A to the negative of the B and then using A's wiring to go to the switch? Are LED work lights sold with a harness to avoid doing this?

Thanks for any help!

 

[GreensvilleJay]

yes, it's taht simple.....

 

[dirtydeed]

Yes, correct. However, I'd suggest using relay/switch. Here is a decent harness that includes the lighted switch, relay and fuses.

I used this for my installation. I had to add some additional wire but this will get you started. For $10, it's well worth it.

https://www.amazon.com/gp/product/B071ZPX32N/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

[bluedunn]

yes, it's taht simple.....

Finally - something simple!!! Thanks

 

[Rosher18]

Yes, correct. However, I'd suggest using relay/switch. Here is a decent harness that includes the lighted switch, relay and fuses.

I used this for my installation. I had to add some additional wire but this will get you started. For $10, it's well worth it.

https://www.amazon.com/gp/product/B071ZPX32N/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

This, 100%. If you find a wire that's only hot when the key is on for the "low current" side of the relay, you won't be able to leave your lights on when you shut down.

I ran my high current wire straight off the always hot heavy gauge wire coming into the glow plug switch, since I have a 120W light bar on the switch.

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[chim]

Remember that "D" in LED stands for Diode. Unlike filament lights, LED's care about polarity.

 

[seanbarr]

Yes, correct. However, I'd suggest using relay/switch. Here is a decent harness that includes the lighted switch, relay and fuses.

I used this for my installation. I had to add some additional wire but this will get you started. For $10, it's well worth it.

https://www.amazon.com/gp/product/B071ZPX32N/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Hold on.

With two LED lights, a relay is often not necessary. The OP should share what switch he has and from there, get a proper recommendation. Chances are, no relays would be required.


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[Rosher18]

Hold on.

With two LED lights, a relay is often not necessary. The OP should share what switch he has and from there, get a proper recommendation. Chances are, no relays would be required.


Sent from my iPhone using Tapatalk

OP, I suggest you run a quick Ohm's Law calculation based on the wattage of all LEDs that will run on the switch.

Divide total watts by voltage to get current.
Example, my light bar is 120W and if I assume 12V while running (it will be higher due to the charging system running) I get 10A, which is a lot for most switches. Check the amperage rating for the switches you want to use or do the relay harness.

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[dirtydeed]

Hold on.

With two LED lights, a relay is often not necessary. The OP should share what switch he has and from there, get a proper recommendation. Chances are, no relays would be required.


Sent from my iPhone using Tapatalk

Never mind.

 

[NHSleddog]

Use a meter to measure the actual draw from the lights.

I bought a pair or "120 watt" LED's

They both measured 21 Watts at startup and 19 when running.

 

[i7win7]

LED's are very energy efficient. Volts x Amps = Watts aslo Watts / Volts = Amps. Two examples:

60 watt lightbar 60/12=5 if adding your own wiring use a 6 amp fuse
2 10 watt lights 2*10=20 total watts 20/12=1.666 amps use a 2 amp fuse
A relay is not needed, power is low enough it could be plugged into lighter port.

I have a trailer mover with winch attached- winch has 50 amp fuse. Went to Walmart, bought wiring kit for power amp. The big one for heaviest amperage draw. Replaced 80 amp fuse with 60. Added 12 volt power connectors (forklift shop cheapest source) did same for jumper cables (can jump car or tractor).

Made own ROPS bracket, added 4 sets of LED lights + radio, waterproof box with fused distribution block inside.

 

[GreensvilleJay]

re: LED's care about polarity.

Yes, bare, raw, out of the box ones do BUT ....a good mfr can easily make them work on -ve gnd, +gnd or AC power. I've been doing that for 40 years.
I use 16Watt CREE LEDs, run constant current and don't care what kind of 12 volts you give them.

 

[BManFX4]

Actually, it depends on the operating range of the LED lights you are using. If you wire them in series you will have exactly half of the voltage applied to each light. So in a 13.8VDC situation like your tractor, there will be 6.9VDC across each light.

In all likelihood you are better off wiring them in parallel, like you suggested.

Almost all commercially sold LED lights will have polarity marked on them - usually with the + wire being red and the other black or blue or, sometimes, white. You never know with the chinese stuff especially.

 

[chim]

re: LED's care about polarity.

Yes, bare, raw, out of the box ones do BUT ....a good mfr can easily make them work on -ve gnd, +gnd or AC power. I've been doing that for 40 years.
I use 16Watt CREE LEDs, run constant current and don't care what kind of 12 volts you give them.

I'd be interested in knowing more about that. I pretty much got out of the field when metal halide was edging out mercs and sodium junk. Those and the twin / quad tube CFL's that were a flash in the pan.

The only LED's I have experience with are the 12v lights and flashers I use on my tractors and they all care about polarity. I have run into misc. strips and hi bay lights with AC (normal building stuff).

 

[i7win7]

https://www.amazon.com/slp/full-wave-bridge-rectifier/upjuh2ypvo8m32n

full-wave-bridge-rectifier has 4 wires or terminals. A +positive and a -negative the other 2 are AC +- switches 60 times per second on US power grid (you can feed AC wires with DC). All LED bulbs running on AC have them as well as other electronics to lower voltage (some, not all are dimmable)

 

[GreensvilleJay]

LEDs by their nature are 'constant curent' devices, rated for xxx ms of current. They need a certain voltage though to begin to light up ,any more and they'll burn out. White LEDs are about 3.4 volts, so most '12V ' LEDs are actually 3 LEDS in series with a simple( cheap) resistor to limit current. The problem is in controlling the intensity and life of the LED. 99.44% of the market for headlight/worklight' LEDs don't need to be dimmed, so they can be nmade real cheap.
Dimmable LEDs use either varying constant current(CC) or PWM modules. CC is technically better for the LED, PWM is cheaper.
I still have some 40 year old LEDs running here, CC mode.

 

[chim]

OK, I do have a familiarity with rectifiers, and a small amount of experience with LED lighting control with drivers and LV controls. I thought the discussion was about the LED vehicle type lighting we use on tractors. Also found it interesting the way vehicle S/S/T lights vary the blinking to change the perceived brightness. LED tail light strobing is a little distracting for me.

 

[bluedunn]

If I have an auxiliary fuse panel that is switched, and is connected to a relay already...do I then need to also wire the two LED work lights into a separate relay? Or is that over-relayed? Guys, sorry for what is probably a dumb question, but I'm pretty green when it comes to electrical - I feel like I can tackle this, but do want to make sure it's not going to fry my electronics or cause an issue.

Thanks for the help!

 

[i7win7]

The purpose of a relay is to use a low amperage circuit to control a high amperage circuit. Your key switch can not handle the 100's of amps pulled by the starter (starter solenoid is a relay). Adding electrical devices existing circuits can be tricky fuses protect existing devices - using larger fuses can melt wiring harness.

Better to use lighter circuit if you never use a lighter (10-15 amps check your manual). Adding fused wire directly to battery is better. Now if you do not want someone turning on the lights and running down battery, it is time to add a relay. Your added wires go across the switch contacts, the coil contacts (one side grounded, other to switch ACCessory terminal)

 

[bluedunn]

The purpose of a relay is to use a low amperage circuit to control a high amperage circuit. Your key switch can not handle the 100's of amps pulled by the starter (starter solenoid is a relay). Adding electrical devices existing circuits can be tricky fuses protect existing devices - using larger fuses can melt wiring harness.

Better to use lighter circuit if you never use a lighter (10-15 amps check your manual). Adding fused wire directly to battery is better. Now if you do not want someone turning on the lights and running down battery, it is time to add a relay. Your added wires go across the switch contacts, the coil contacts (one side grounded, other to switch ACCessory terminal)

Obviously I'm missing something - if I already have a fused (in-line fuse to battery) auxiliary fuse panel, that only is live when the key is on, and has a relay between the battery and the aux. panel...then would I still need to run both LED lights to a relay first, then to the fuse panel such that the lights are only able to be turned on when the key is on?

Again, sorry if this is a stupid question.