Light switches with resisters

[RPCW]

I have two light switches designed to be used with cutout relays with broken/torn resisters. I measured 2 ohms across the resister on a good original functioning switch. Can I replace the broken/torn resisters with new 2 ohm resisters from Radio Shack (designed for 6v) ? Thanks in advance for any advice!!

 

[Anonymous-0]

A 2 ohm resistor doesn't know from six or twelve volts you will need a 2 ohm rated for the current load(amps) you will be pushing thru it.

 

[RPCW]

Gary - thanks for the reply! I would assume that the load would be variable with rpms with about 30amps at top load. Would a 2ohm 30 amp resister be acceptable?

 

[Mark57_420]

Resistors are rated by power (Watts). That is V*I, or if you just know the voltage, (V*V)/R. {Voltage squared divided by Resistance}. So, on a 6V system a 2-ohm resistor will need to be at least 18W. The next standard size is 25W.

Make sure you solder the wires to the terminals good because a poor connection could easily add more than 2 ohms to the circuit.

 

[Anonymous-0]

Field current is probably only a couple amps at 6 volts, so you don't have to carry 30 amps in the control resistors. Look for a wire wound resistor at RS or Mouser (www.mouser.com) the same physical size as the originals with your switch and they will handle the power adequately.

Gerald J.

 

[John T]

RP, Id expect a resistor, for it to work as a field current lowering device, to be a power rated unit around 2 to 3 ohms at 25 watts or more. Rat Shack has such low ohms units they identify as Power Resistors I believe. Its possible to mix n match using series or paralell combinations to get the more exact ohms and power needed. Dont forget that light switch needs a good ground source to carry the current that first passes through that current limiting resistor. Also dont mix up any light dimming resistors/circuits with those genny field resistors

John T

 

[Anonymous-0]

Your assumptions are wrong.Ive used a 10 watt resistor.Check the price of a new light switch at A JD dealer.A 20 watt will work if you cant find the 10 watt.2 to 3 ohms will work.