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We bought a house 3 years ago and it came with a Samsung Refrigerator. For some reason the previous owner bought a fridge with an ice maker and never hooked it up. Well you cannot disable this feature without causing an error that will not go away.

I've replaced the motor in the unit with a resistor but I just want to make a reality check as I am not an engineer.

The motor is a Mabuchi model RF-370CB-13490. I could not find the specs for this exact model but I found the series spec sheet here

So I went with the high side for both voltage (16V) and amps (0.011) with no load which would give me 0.176 watts. I measured the resistance through the motor at 20 ohms. So I installed a 56 ohm 1/2 watt resistor that I had laying around. Now obviously ohm's law says the resistance should be around 1455. Should I install a resistor with a value near 1455 or is the 56 ohm ok? I just don't want to cause a fire.

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    \$\begingroup\$ The DC resistance of a motor has very little to do with its current consumption when it's running : unless it is stalled, when it draws enough current to quite possibly burn out. This suggests Ohms law would be a better guide than the DC resistance value. \$\endgroup\$
    – user16324
    Feb 22, 2016 at 15:12
  • \$\begingroup\$ If the electronics is smart, you won't fool it with a simple resistor, because the motor is an electromechanical device that works reversible - at any time is a motor and generator. If your electronic senses the generated voltage ie for speed control it will trip an error equaly. \$\endgroup\$
    – Marko Buršič
    Feb 22, 2016 at 15:35

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Notice that on the spec sheet you linked, "stall" draws 0.32A with the highlighted motor, while "no-load" it draws only 0.011A.

If you plan to replace the motor with a resistor to "fool" the control electronics, then I would recommend aiming for the "at maximum efficiency" stat of 0.059A, thus about a 220-ohm resistance for the 'nominal' 12V supply, or around 300-ohm resistance for 'max' 16V (with >= 0.5W power dissipation rating).

Once you've tried with the 200-ohm load, adjustments can be made to alter the impedance to more closely/elablrately fit the motor's start-run-jam cycle resistance curve, if that becomes necessary.

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  • \$\begingroup\$ I will try a 1 watt between 200 and 300 ohm. Right now it is working with the 56 ohm 1/2 watt but would rather be safe than sorry. Thanks for the input. \$\endgroup\$
    – user3348186
    Feb 22, 2016 at 18:37
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From my comment: if you want to fool the electronics then a RC may be more usefull: U_nominal=12V; I_stall=0.32A -> R_stall= 12/0.32 = 37.5ohm; I_noload = 0.011A -> R_noload = 12/0.011 = 1090 ohm R2=1090-37.5, the C1 has to be choosen to simulate the back EMF constant L/R = cca RC. For real values you can for example choose R1: 33ohm, R2: 1.1kohm, C1: 680nF

schematic

simulate this circuit – Schematic created using CircuitLab

Maybe a larger cap, will do better like 4.7uF

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