Voltage drop

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JonathanR
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Voltage drop

Post by JonathanR »

Another electrickery question as this would not be my chosen subject!

I have fitted 5 small led lights (see pic below) inside the van under the wooden side panels (High top). Took the feed from the same line as an existing light running from leisure battery via a switch.
I have fitted them in series and since the tails are short have had to add extra wire in between each LED and then run a long length to complete the circuit. The distance between first and last LED is 1.6 meters although have not wired the last one in.

I am disappointed with the output. Just a dull glow and certainly not enough to illuminate the worktop. More romantic than floodlit.

So I imagine it’s all down to voltage drop. Although my leisure battery is on its way out and only kicks out 10 volts. The wire I have used is 5 amp and I have used a lot of chocbox connectors. I do not know the wattage of the LEDs.

So do I go for thicker wire or thinner, should I split the run and have two parallel feeds of 2/3 LEDs, use a better way of connecting the LEDs or chuck the LEDs and buy some with a higher wattage/brighter.

I want to do the same the other side of the van running off the same switch so will be an even longer run.

Many thanks for help
J
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mrhutch
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Re: Voltage drop

Post by mrhutch »

put the leisure battery on a charger and test again.. 10V will be the problem
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Forden341
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Re: Voltage drop

Post by Forden341 »

What voltage are the led’s?
If they are rated at 12v then they should be connected in parallel.
Is your 10v reading at the battery or at the led, if it’s the battery then charge or replace it but if it’s at the end of your circuit then may well be high resistance in your connections or wiring.

JonathanR
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Re: Voltage drop

Post by JonathanR »

Thanks for helpful input.

10 volts is at the battery end.
Bought the lights at Busfest so assuming 12 Volt.

Have put battery on charge and even in daylight they look brighter. Albeit it’s now at 14V while connected to charger. Will check in dark tonight when fully charged. Will also order a new leisure battery as it’s been on my list for a while, but normally we live without lights during summer.

What would be the best terminal to use for connecting lights in parallel?








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Forden341
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Re: Voltage drop

Post by Forden341 »

If they are 12v leds and you have them wired in series then with 5 connected they’d only be getting a little over 2v each. I’m surprised they light at all, I solder my connections where possible as the crimp on bullet connections are terrible for coming lose on the small gauge wires.
Have you tried just connecting one led to a 12v source?
When in parallel they will all be the same.

JonathanR
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Re: Voltage drop

Post by JonathanR »

Thanks for all the help. Rewired in parallel, and after a lot of reconnecting now all up and running. Lights appear much brighter but only tonight will confirm.

Image

Have kept chocblox until I’m sure I’ve got it right, had another attempt to connect up last light on the run and installed the same on the sliding door side.Then I’ll tidy

Also I’m awaiting LEDs to fit inside the existing original two strip lights.

Another project is to fit two sensors to measure temp inside and out. The inside temp will show in red and outside in blue.

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