LightHawk? Wall Switch Occupancy Sensors

Status
Not open for further replies.
If the yoke is plastic, why bother with the EGC?
On a second note, doesn't your circuit have a EGC?
 
edward said:
If the yoke is plastic, why bother with the EGC?
On a second note, doesn't your circuit have a EGC?
Click to expand...

That's what I'm saying, I don't need to use the EGC, so is there anything wrong with connecting the green ground wire from the occ sensor to the grounded conductor, to avoid objectionable current on the EGC?
 
Someone will correct me or be able to offer more on this but, i think devices like that use the egcfor the LED, photocell. I think it's somehow not objectionable current because its so small? Becuase of the instuctions I'd connect it to the egc personally.
 
Last edited:
I've never hooked up one in my life but if I had to bet I'd say that the line was the voltage in ,the load would be the switch leg (so to speak) and the neutral would go to the load and not the sensor and I would hope there is a ground terminal on the sensor.The device that senses I guess would be a motion sensor and it would be a internal biasing operating like a photo cell or similar on an electronic component(probably a transistor) that would allow the switch to conduct or gate voltage to a internal relay,,,,,,,,,,,,,,,(a black box smart device)

dick
 
wirebender said:
I am installing LightHawk™ Wall Switch Occupancy Sensors on a project.
They have a line, load and ground wire, no neutral.
But the yoke is plastic so I'm thinking I can connect the ground wire to the neutral and actually be more code compliant except for going against the instructions.
Am I thinking wrongly?

http://www.hubbell-automation.com/c...instructions_files/hba_lighthawk_instruct.pdf
Click to expand...

What makes you think that this would be more code compliant. I would look at 110.3(B) to start. IMO it is a BAD idea to connect the EGC with this or any Grounded, Neutral conductor.
 
1793 said:
What makes you think that this would be more code compliant. I would look at 110.3(B) to start. IMO it is a BAD idea to connect the EGC with this or any Grounded, Neutral conductor.
Click to expand...

From the ROP on 404.2(C)

"Occupancy sensors are permitted by UL773A to have a current of
up to 0.5 ma on the grounding conductor. This is allowed because the operation
of an occupancy sensor requires a low level standby current. The standard
permits this current on the grounding conductor because in a typical installation
there is no grounded circuit conductor in the switch box which can be used as
the return conductor for the standby current."

It appears to me that the green wire is not actually a ground wire since the device is plastic. The purpose of 404.2(C) is to someday be able to do away with this 0.5ma on the grounding conductor and place it on the grounded conductor where it belongs.
In my situation, the grounded conductor is there so why not use it? :?
 
wirebender said:
From the ROP on 404.2(C)

"Occupancy sensors are permitted by UL773A to have a current of
up to 0.5 ma on the grounding conductor. This is allowed because the operation
of an occupancy sensor requires a low level standby current. The standard
permits this current on the grounding conductor because in a typical installation
there is no grounded circuit conductor in the switch box which can be used as
the return conductor for the standby current."

It appears to me that the green wire is not actually a ground wire since the device is plastic. The purpose of 404.2(C) is to someday be able to do away with this 0.5ma on the grounding conductor and place it on the grounded conductor where it belongs.
In my situation, the grounded conductor is there so why not use it? :?
Click to expand...

I am in agreement with you. Not knowing anything about the control device you have, it sounds like the green wire is isolated since there is a non metallic yoke, but it is probably there for a reason. If you do not connect it to something grounded the device likely does not work. It likely is carrying less than the allowed .5 ma, but still is carrying current. If I verified this was isolated from other connection to the EGC I likely would connect it to the neutral conductor if it is available at the switch location.
 
wirebender said:
From the ROP on 404.2(C)

"Occupancy sensors are permitted by UL773A to have a current of
up to 0.5 ma on the grounding conductor. This is allowed because the operation
of an occupancy sensor requires a low level standby current. The standard
permits this current on the grounding conductor because in a typical installation
there is no grounded circuit conductor in the switch box which can be used as
the return conductor for the standby current."

It appears to me that the green wire is not actually a ground wire since the device is plastic. The purpose of 404.2(C) is to someday be able to do away with this 0.5ma on the grounding conductor and place it on the grounded conductor where it belongs.
In my situation, the grounded conductor is there so why not use it? :?
Click to expand...

I would follow the Instructions, why 2nd guess the Manufacturer? If it were me and I wanted to make this change in connections, I would call the Manufacturer and ask them. Just my .02.

Let us know what you decide to do.
 
Thanks for the input, everyone.
Guess I'll attach the green wire to the egc even though IMO it should go on the grounded conductor.
Not my company so I better not screw up the bosses warranty.
 
Status
Not open for further replies.
Top