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dc circuit length?

dc circuit length?

dc circuit length?

(OP)
Does anyone know how far you can effectively run 24VDC. We have an application where we need to run it about 300' to a 1/2 amp load. Thanks

RE: dc circuit length?

Depends how thick the wire is and how big a volt-drop you can stand. For a 300' run you will be looking at a fairly heavy cable to keep volt-drop to reasonable limits. Post a bit more detail of your load and what supply variation it can handle and someone will probably give you a cable size.
 

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  Sometimes I only open my mouth to swap feet...

RE: dc circuit length?

(OP)
Basically it will be supplying two 24VDC siren/strobe lights for audio/visual status of a process. Each strobe is .56 amps. I would tend to think it could stand a drop of a couple volts. If anyone could give me a rough idea of wire size that would be great. Thanks

RE: dc circuit length?

16 ga. wire has a resistance of 4 Ohms per 1000 feet.  You have 600 ft. so the resistance is 4 x 0.6 = 2.4 Ohms.  The voltage drop would be V = IR = 0.5 x 2.4 = 1.2 Volts

RE: dc circuit length?

It might be a good idea to put a 1,000 to 4,700uF at the end of that run since the type of loads you have are pulsing.  Momentary current can be considerably higher than the average and this may cause problems.

Just yesterday I was playing with a GPS I had pucked up for $5  bucks with a battery case problem.  My bench power supply had a 5 ohm resistor to jumper to the center connector so I could use a standard banana pair.  The GPS draws less than .06A, but I couldn't get it to turn on till I shorted the 5 ohm resistor!

RE: dc circuit length?

I note that you initially said a 1/2 amp load and now you are saying two 0.56A loads.

sreid's calculation is based on your initial data of 0.5A.

RE: dc circuit length?

This should be about right:

600' (2x300)
24VDC

1.0 amp @  3% drop =>  8ga
0.5 amp @  3% drop => 10ga
1.0 amp @ 10% drop => 12ga
0.5 amp @ 10% drop => 16ga

NOTE: Please be sure to adhere to ABYC standards

NOTE: Use ANCOR tinned & stranded wire in marine applications

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