Sharing supply power for PLC

[>:D]

Hi,

I'm challenging myself to install a PLC for the first time. I went for a Micro830 48QWB, since it has 48 I/O and free software (CCW). From my understanding it only needs about 2 amps to power it. I have a 6 amp transformer that'll be more than enough. Can I use the same 24vdc to power some inputs to the PLC? I'll likely just be using push buttons, possibly a sensor or two (though unlikely). Would this be a problem in the long run or no?

Thanks.

 

[I_Automation]

You can use the external 24VDC power you power up the PLC with for sensors and devices. This is commonly done.


The DON'T is for 120/240VAC powered PLC's that have a 24VDC output on it. Don't use that power outside of the control panel or for anything other than indicator lights, If that gets overloaded it could take down the PLC. If that gets some foreign frequency injected it could interfere with the PLC working.

 

[>:D]

You can use the external 24VDC power you power up the PLC with for sensors and devices. This is commonly done.


The DON'T is for 120/240VAC powered PLC's that have a 24VDC output on it. Don't use that power outside of the control panel or for anything other than indicator lights, If that gets overloaded it could take down the PLC. If that gets some foreign frequency injected it could interfere with the PLC working.

Thanks! That makes sense. Some friends of mine suggested similar, but it doesn't hurt to double check. I was also thinking of using the 24vdc to activate some relays. The relays would have external 120vac power derived separately from the PLC, and the 24vdc would come from the PLC's power supply (which will be controlled through an output on the PLC). I assume as long as I keep the FLA in check it'll be fine?

 

[I_Automation]

As long as you stay within the limit of the power supply you will be fine, and a 6 amp power supply can handle an amazing amount of relays along with the PLC as long as you don't try to use 24V contactors and solenoid valves (have a interposing 24V coil relay control 120VAC for those)


EDIT: I don't mean small 24V IEC contactors, I'm talking 15 to 50 HP+ rated larger contactors.