turning switching power supply removed from computer on and off

Thread Starter

PeteHL

Joined Dec 17, 2014
473
The green wire connected from the power supply to a plug is identified as R/C. If this stands for "remote control", then I assume that the power supply is turned on by a voltage pulse between the green wire and ground.

The coding printed on the power supply does not identify which wire is ground, but the harnesses coming out of the power supply include a black wire that is not identified. Can I assume that the black wire is ground?

To turn on the power supply, what voltage should I connect to the green wire, and do you think that the turn-on voltage must be a single clean square wave (conditioned)?

My method of turning it off would be to remove AC power to the supply. Would this be safe practice with the supply?

Thanks in advance for your responses,

Pete
 

danadak

Joined Mar 10, 2018
4,057
To turn on normally a pulse has to be applied, a pulse to ground as the
green wire is pulled up to +5.

The pulse has to be a minimum of ~ .5 sec, a max of somewhere around 2 -3
seconds. A longer pulse will turn off supply if it is running.

Best way is a debounced button driving an open collector BJT, or open drain MOSFET
to ground the pin/wire with the pulse.


Regards, Dana.
 

Thread Starter

PeteHL

Joined Dec 17, 2014
473
To turn on normally a pulse has to be applied, a pulse to ground as the
green wire is pulled up to +5.

The pulse has to be a minimum of ~ .5 sec, a max of somewhere around 2 -3
seconds. A longer pulse will turn off supply if it is running.

Best way is a debounced button driving an open collector BJT, or open drain MOSFET
to ground the pin/wire with the pulse.


Regards, Dana.
With the power supply that I have, I can turn it off and on by connecting a solid black and the green wire to the throw and pole terminals of a SPST (mechanical) switch. DC voltage on the green wire measured 2.3V. :(
 

AlbertHall

Joined Jun 4, 2014
12,345
With the power supply that I have, I can turn it off and on by connecting a solid black and the green wire to the throw and pole terminals of a SPST (mechanical) switch. DC voltage on the green wire measured 2.3V. :(
Yes, that sounds normal. When the green wire is grounded the PSU is on and when the green wire is left floating the PSU will be off.
 
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