ECN Forum Forums General Topics of the Trade General Discussion Area 208V Photo Cell.. doesn't work

If the cell info says 208 - 277 Volts it needs that between phase and neutral.

Otherwise the bimetallic strip will not heat up enough, or the internal electronics doesn't work at the undervoltage of 120 Volts.

Normally at switch on (daytime) the load should come on for about a minute and then switch off, to show that the circuit works.

If the lights stay on, either the control voltage is not correct 120V instead of 208 - 277V or the contacts have fused together because of overload.

Whats the phase to phase voltage? (A-B, B-C, A-C) If all are roughly 240 - its a delta. But you say all 120 to ground... 208 phase to phase, with all 120's is a wye system. Just wondering why you mentioned a high-leg earlier???? As you would only get one on a delta....

As mentioned, the initial current can be much more, and can fuse contacts on you. And it may seem contradictory - but that unit may only be rated at 1700VA at that voltage?

http://www.intermatic.com/Default.asp?action=prod&pid=9163&sid=237&cid=52&did=5


I can find the wiring diagram on intermatics site for that model #, but it sounds odd that if it has a neutral it being rated for 208~277. And couldnt tell if that white were to be phase connected for 208 or 240???? Still got the destructions?????

It may have this in it:

Heres another fun one - I've made this mistake before - Did you wait a while for it to come on? Sometimes it takes ~10 minutes...

From what I read I think you are only feeding 120V to the eye element.
The neutral or rather the WHITE wire off the photo-eye will have to be connected to one of the phases.. If you have your lights wired between say B&C phases, then connect the photo eye between B&C or whatever you are using..
Better yet, picture it like a standard 120V circuit, where one of the phases is your hot, but the other phase you use is "neutral" even though it isn't and wire it up as if its a regular 120V circuit..

A.D

aldav53 ,

Connect the White Control Circuit Lead off the Photocell, to the other side of the 208 Volt 1Ø Circuit.
The Photocell's internal Relay Coil is designed to be driven from 208 Volts up to 277 Volts, so the Control Circuit must be within those parameters.

As it is now, the Control Circuit is only being driven at 120 Volts, so that internal Relay is most likely trying to pull in (may even be an audible "chirping" sound emitted).

I do agree with the use of Lighting Contactors for this type of Lighting option - mostly because the Photocell leaves a "Live" Ungrounded Conductor at each of the Fixtures when they are off during daylight hours, and someone may get "Shockenzeeassennoffer" (Shocked) if servicing a Lamp - due to the Screwshell being "Hot" still.

Multipole Contactors with all Ungrounded Conductors run through them, would reduce the potential for "Shokkenzeeassenoffer" by opening all the Ungrounded Conductors, plus eliminate the large load through the Photocell.
Not that this is a "Must Do" thing - you likely bid the job using a simple Photocell for the sole controller, and this is code compliant.

Anyhow, simply connect that White Lead to the "Other Side" of the 208 Volt Lighting Circuit, and the thing should work.
The Photocell's relay lead is "White" by "Default", so don't let that confuse you.
The White wire you used for the Photocell may be used to pull in a "Non-Identified Color" (i.e. Black, Red, Blue), which may be terminated to the "Other Side" of the 208 Volt Circuit at a convenient point - or if both Ungrounded Conductors run through the same box where the Photocell is at, simply terminate the White Photocell lead to the "Other Side" of the Circuit at that box.

Good luck! Let me know if smoke comes out

Found out, hooks in lineBlack in red out with the 120v side and the load side ties in with the white.

"load side ties in with the white"

Dont ya mean with the other phase the load is controlled with? As writen it would sound like the load were through the photo cells control side.

Correct me if I am wrong.... It seems to me your trying to run the photo cell with 120 volts, there is no neutral connection on a 208 0r 240 volt photo control, and a 400W MH is 2.3 A. @208V, a contactor controlled by PC, or PCs in each fixture might be another option.