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I am trying to control a linear actuator using a cheap remote controlled 2 channel relay (it controls a gate for my workshop dust collector). I'm think it's as simple as connecting each relay the same way...

NO: +12v from power supply

Comm: one motor line on relay 1 and the other motor line on relay 2

NC: neutral (ground? Or -12v???) from power supply

This gives me the following voltages on the common lines...

No relays activated = NC / NC = neutral

Relay 1 activated / relay 2 off = NO / NC = +12v

Relay 1 off / relay 2 activated = NC / NO = -12v

Both relay activated = NO / NO = 0V

I feel comfortable I got everything above right except that last line. If I put 12v on each side of the motor then I should have no voltage difference and therefore no current running through.

This thing sits around in one of these states all the time in a remot barn so I just want to confirm nothing is dangerous about my setup.

Is there a better way to do this? If above is safe then I have to remember to shut off each relay once the actuators reaches its end position (closed or open). What I need is a circuit tho if I press 1 it closes (+12v) and if I press 2 if opens (-12v). The linear actuator has a switch that opens once it has rich its final position. So trying to press 1 or 2 more times won't do anything until it goes the other way.

Thanks for any feedback or suggestions.

enter image description here

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schematic

simulate this circuit – Schematic created using CircuitLab

Figure 1. (a) One way. (b) Another way.

Your question was a very hard read. I think you are describing (b) which will work fine.

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It could be a problem if you are using relays that are make before break. This would cause a momentary short circuit on your 12V supply when switching.

From forward to reverse. From reverse to forward. From off to forward or reverse. From forward or reverse to off.

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This design will work, but it is likely to be rather hard on relays unless one includes a transient suppressor to absorb inductive flyback from motor. Normally when using a relay to switch an inductive load one would use a back-biased diode across that load for flyback suppression, but that won't work if the motor may run both ways. An alternative would be to use four flyback diodes: one from each side of the motor to the positive rail, and one from each side to the negative rail.

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