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So, I’ve run into a weird issue while trying to hook up a voltage controller box to two linear actuators. The voltage controller box receives an input of 12V and outputs 12 or -12 depending on what button you press. There are four leads, two pairs of wires for each actuator, and they correctly output the 12 or -12 volts to change the actuator’s direction. However, whenever I hooking up the leads directly to the actuator, the motor does not draw enough current, the voltage does not read 12 or -12, and the motor slightly jolts as if it wants to begin rotating but never actually moves. I began to think there were issues with the relays inside the voltage control box, but then I used dual-ended alligator clips to jump the leads to the motors, and they worked perfectly. They drew about 2.5 amps as expected, and switched directions when the voltage was reversed. They even work if only one of the two leads has the alligator clips jumping it to the motor ground!

The lead’s wore gauge is 16AWG, and the alligator clips’ gauge is 18. The resistance of the alligator clip is about 1 ohm. The motors are rated for 12-24 volts and up to 14 amps.

I just find it odd that it takes the alligator clips to ensure the motor draws enough current. I even replaced them with different wire of the same gauge and it didn’t work. Then tried a 1 ohm resistor as a substitute for the alligator clip. Still didn’t work! If anyone could explain this weirdness to me, it would be greatly appreciated.

Edit: the leads have a soldered on form M5 connector that attach to a screw terminal block on the linear actuator. They are new and not oxidized, so I don’t think that the alligator clips are “biting” into the terminals to provide better connection.

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    \$\begingroup\$ You never mentioned what methods of connection you used other than alligator clips. My bet is oxidized terminals or wire that alligator clips can punch through. \$\endgroup\$ – DKNguyen Apr 27 at 4:01
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    \$\begingroup\$ What is the current rating of your power supply and switch box? It's entirely possible that a good connection is causing an overload shutdown, while the undersized clipleads add enough extra loss to keep the current below the trip threshold. Questions such as yours which are missing critical detail don't really last here, because they cannot be answered on a factual basis. \$\endgroup\$ – Chris Stratton Apr 27 at 4:27
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    \$\begingroup\$ @ChrisStratton current rating of voltage supply is 10A and the switch box has a rating of 14A. I apologize for the missing detail, descriptive skill is definitely something I need to home. What might you recommend to ensure that I can keep the current below the trip threshold? \$\endgroup\$ – Luke Parker Apr 27 at 4:37
  • \$\begingroup\$ Seems like you are using an incompatible selection of parts, with loads that require more power than you can supply. Maybe you can wire your actuators in series if they are simple coils; they will be weaker but might not overload the supply. But generally this project seems not well thought through. \$\endgroup\$ – Chris Stratton Apr 27 at 5:11
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    \$\begingroup\$ Some photos of your connections would be useful. \$\endgroup\$ – HandyHowie Apr 27 at 7:58

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