Soleniod Valves Grounding

[Richard Carlson]

What is the industry standard for using the ground wire when energizing a solenoid from a PLC 120VAC output

 

[Dennis Alwon]

Are you talking the equipment grounding conductor or the neutral (grounded conductor). The equipment grounding conductor is not to be used as a current carrying conductor.

 

[Richard Carlson]

we fuse the output and the common goes back to the common from the Breaker panel

 

[GoldDigger]

What is the industry standard for using the ground wire when energizing a solenoid from a PLC 120VAC output

Are you asking whether the solenoid needs to be grounded? Or what size wire to use? It seems to me "likely to become energized" so an EGC or bond would have to be supplied.
The "120V output" from a PLC could be a power-limited output or could be subject to standard wiring rules.

 

[don_resqcapt19]

We use the conduit and the LFMC as the EGC for that application and do not connect anything to the green pigtail on the solenoid.

 

[Richard Carlson]

Are you talking the equipment grounding conductor or the neutral (grounded conductor). The equipment grounding conductor is not to be used as a current carrying conductor.

I'm coming out of a PLC 120VAC output 'fused' at 4 amps and controlling a 4 solenoids with the common going back to a common in my PLC cabinet, do I need to run grounds out to the solenoids

 

[roger]

What is the industry standard for using the ground wire when energizing a solenoid from a PLC 120VAC output

As Dennis said, the EGC can not be used as current carrying conductor which seems to be what you are asking.

Roger

 

[GoldDigger]

As Dennis said, the EGC can not be used as current carrying conductor which seems to be what you are asking.

Roger

Post #5 (passing in the night) removed that seeming. It is just a question of whether some sort of EGC (wire or raceway) must be run to the solenoids.

 

[Richard Carlson]

Are you asking whether the solenoid needs to be grounded? Or what size wire to use? It seems to me "likely to become energized" so an EGC or bond would have to be supplied.
The "120V output" from a PLC could be a power-limited output or could be subject to standard wiring rules.

The neutral from the PLC cabinet is bonded to ground do I still need to use the green wire back to the cabinet

 

[roger]

I'm coming out of a PLC 120VAC output 'fused' at 4 amps and controlling a 4 solenoids with the common going back to a common in my PLC cabinet, do I need to run grounds out to the solenoids

We have a communication problem here. If what you are calling a "common" is by design a current carrying conductor and you are asking about bonding the solenoids, the answer with the information you have given is yes, the solenoids need to be bonded with an Equipment Grounding Conductor.

Roger

 

[ptonsparky]

We have a communication problem here. If what you are calling a "common" is by design a current carrying conductor and you are asking about bonding the solenoids, the answer with the information you have given is yes, the solenoids need to be bonded with an Equipment Grounding Conductor.

Roger

Or the EG can be the properly bonded metallic raceway. FMC, LFMC...etc

 

[kwired]

We have a communication problem here. If what you are calling a "common" is by design a current carrying conductor and you are asking about bonding the solenoids, the answer with the information you have given is yes, the solenoids need to be bonded with an Equipment Grounding Conductor.

Roger

I think OP possibly needs a better understanding between the differences between a "grounded" conductor and an "equipment grounding" conductor. He needs to forget about the fact he has a PLC and forget that he has a solenoid for a moment and understand the general rules of power source, services/and or feeders, separately derived system, then grounding and bonding, and the fact that he has a load that happens to use a "grounded" conductor as one of its supply conductors.

Richard - you have a load that uses a "grounded" conductor. This conductor, though it is tied to the "grounding conductor" back at/near the source is not permitted to bond to non current carrying metal objects beyond the bonding jumper at/near the source. To bond beyond that point allows normal operating current to flow through unintended paths of metallic components of equipment, which can cause other problems with stray currents and voltages. In your application you need a separate neutral and equipment grounding conductor to your solenoid. The neutral will be a conductor with insulation on it, the equipment grounding conductor may be a "conductor" or it could be metallic raceways or cable sheaths if they meet requirements in art 250 part VI.

 

[ghorwood]

Solenoid EGC

Solenoid EGC

DO NOT tie the solenoid ground wire to the common of your control circuit. You may get weird problems, and funny readings should you try to ring it out with your meter. The circuit may or may not work. Use your raceway as a ground if you want. I would pull in a separate EGC.

 

[SceneryDriver]

Pretty simple:

black wire(s) are HOT wires - they go to the PLC outputs (in this case)

white wire(s) [or the other power wire from the solenoids' coils] are the NEUTRAL wires - they go to the neutral bar/terminals in your panel

green wire(s) are the GROUND wires - if they're present, then they go to the ground bar/terminals in your panel



How much difference in time and money can it possibly make to pull the green wire(s)?



SceneryDriver

 

[don_resqcapt19]

...
How much difference in time and money can it possibly make to pull the green wire(s)?

SceneryDriver

The material goes up by a third and the labor goes up a bit.

 

[roger]

The material goes up by a third and the labor goes up a bit.

I agree with Don and to clarify my other posts, when I am saying EGC I am not saying it needs to be a wire, it can be any of the EGC's recognized in 250.118.

Roger

 

[kwired]

Pretty simple:

black wire(s) are HOT wires - they go to the PLC outputs (in this case)

white wire(s) [or the other power wire from the solenoids' coils] are the NEUTRAL wires - they go to the neutral bar/terminals in your panel

green wire(s) are the GROUND wires - if they're present, then they go to the ground bar/terminals in your panel



How much difference in time and money can it possibly make to pull the green wire(s)?



SceneryDriver

What do I do if the solenoid has just two red wires? hmy:

A third conductor is one third of the cost of conductors as mentioned. Maybe not too big of a deal is the run is only 10 feet, but what if it is 1300 feet between the controller and solenoid valve and you already have some other qualifying EGC?

 

[don_resqcapt19]

What do I do if the solenoid has just two red wires? hmy:...

It has only been in the past 10 years or so that I have seen the solenoid coil with the green wire. Prior to that, if there were any metal exterior parts, the only EGC that you could use would be the raceway that connected to the solenoid.

 

[kwired]

It has only been in the past 10 years or so that I have seen the solenoid coil with the green wire. Prior to that, if there were any metal exterior parts, the only EGC that you could use would be the raceway that connected to the solenoid.

Can't speak for all solenoid valves, but ASCO "Red Hat" valve coils have had a green wire for at least 20-25 years from my experiences with them.

 

[don_resqcapt19]

Can't speak for all solenoid valves, but ASCO "Red Hat" valve coils have had a green wire for at least 20-25 years from my experiences with them.

Those are the ones I am thinking of, I don't recall seeing EGCs on those that far back.

It looks like they started using the green wire with the Red Hat II one piece epoxy coils. I don't think the ones you could take apart had the green wire.