Problem with DPDT Rocker Switch and Electric DC Actuators wired in parallel

Thread Starter

MarkTT

Joined Jun 21, 2020
12
I'm trying to wire 4 12V electric linear actuators in parallel using a DPDT rocker switch. When I wire them directly to my power supply they work fine.
When I try wiring in the switch they do not. I have two switches and have tried them both so doubtful it's a faulty switch. Here are the details.

12V 12.5 amp 150W DC power supply
4 12V 3 amp linear actuators wired in parallel
12V 30 amp DPDT rocker switch

Any help would be greatly appreciated.
 

djsfantasi

Joined Apr 11, 2010
6,532
I'm trying to wire 4 12V electric linear actuators in parallel using a DPDT rocker switch. When I wire them directly to my power supply they work fine.
When I try wiring in the switch they do not. I have two switches and have tried them both so doubtful it's a faulty switch. Here are the details.

12V 12.5 amp 150W DC power supply
4 12V 3 amp linear actuators wired in parallel
12V 30 amp DPDT rocker switch

Any help would be greatly appreciated.
Schematic please. Your verbal description is confusing and doesn’t provide sufficient detail.
 

dendad

Joined Feb 20, 2016
3,572
The circuit looks ok.
Try it with just one motor connected. Get that going first.
Then add one at a time.
This will indicate if it is a power supply problem.
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
It doesn't work with even one actuator. A volt meter across the supply terminals of the switch reads 12V with no switch depress. When I depress the switch voltage drops to 0.
 

dendad

Joined Feb 20, 2016
3,572
It could be that the switch is not connected like you have it. Not all switches have the center pins as the common.
Can you take the motors off and see if it still loads the supply down?
 

dendad

Joined Feb 20, 2016
3,572
If one end of the switch is the common, than you will end up with a short on the power supply one direction. Do the motors work one way?
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
This is the switch. I pretty sure the center terminals are for the power supply. Also motors don't work in either direction with the switch in line. When I take the switch out and wire the power supply directly to the motors they work fine.

I'm not actually in my work area right now so I won't be able to try the trouble shooting things you suggest until tomorrow. Thank you for your help. I can update tomorrow.
 

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MisterBill2

Joined Jan 23, 2018
6,383
My guess, based on the photo of the switch, is that a shorted circuit has been created by solder flowing into the crossover strips at the center THAT is the reason for using screw connections instead of losing the screws and soldering wires into the holes.
Of course it might also be that those crossover strips have just been pressed into contact with each other without being soldered. Probably assuring that those strips are not in contact will solve the problem.
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
That looks like it is a ready made switch for this application.
The only thing now is maybe the switch is faulty.
Ok. Problem solved. I went back to the Amazon page where I bought the switch and there was a wiring diagram. It turns out that the power is supposed to be connected to terminals 3 and 6 and the motor to 2 and 5. I had is reversed. It works fine now. It just does not seem intuitive based on the back of the switch.

Thanks all for you help.
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
My guess, based on the photo of the switch, is that a shorted circuit has been created by solder flowing into the crossover strips at the center THAT is the reason for using screw connections instead of losing the screws and soldering wires into the holes.
Of course it might also be that those crossover strips have just been pressed into contact with each other without being soldered. Probably assuring that those strips are not in contact will solve the problem.
Thanks. See my response to dendad. Also, you are right I will use spade connectors on the terminals not solder. I only soldered them because I didn't have any spade connectors.

Thanks for your help.
 

MisterBill2

Joined Jan 23, 2018
6,383
The solution you got makes no sense, unless there is more to the switch than shows. It might be that the switch connects the motor terminals when it is in the off position, other than that, But if it works now leave it alone, don't argue with success.
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
The solution you got makes no sense, unless there is more to the switch than shows. It might be that the switch connects the motor terminals when it is in the off position, other than that, But if it works now leave it alone, don't argue with success.
You are right again. Now it is not working. I have an intermittent problem. sometimes it works and sometimes not. I'm beginning to suspect a bad power supply. I have attached a photo of my setup just in case you can spot something obvious.
 

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djsfantasi

Joined Apr 11, 2010
6,532
Ok. Problem solved. I went back to the Amazon page where I bought the switch and there was a wiring diagram. It turns out that the power is supposed to be connected to terminals 3 and 6 and the motor to 2 and 5. I had is reversed. It works fine now. It just does not seem intuitive based on the back of the switch.

Thanks all for you help.
Can you post the link to the Amazon page where you bought the switch?

Your pic looks good, like it should work. But it’s hard to see a closeup of the connections, how the connecting bars are soldered and what the PIN numbers are.

I’d like to check the Amazon page.
 

djsfantasi

Joined Apr 11, 2010
6,532
You are right again. Now it is not working. I have an intermittent problem. sometimes it works and sometimes not. I'm beginning to suspect a bad power supply. I have attached a photo of my setup just in case you can spot something obvious.
What do you mean by ”sometimes”?
 

Thread Starter

MarkTT

Joined Jun 21, 2020
12
What do you mean by ”sometimes”?
Sometimes when I depress the switch I get no movement of the actuators. Then if I leave the switch depressed the actuators twitch maybe 3 or 4 times with a 4 to 5 second interval between twitches then they finally move. Other times they work normally. I wonder if, as someone above said, the power supply can't supply the startup current. I don't see how that could be though. I have measured the current when they are working with no load on the actuator at 0.3a. The power supply is 12.5a.
 
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