# Phase Loss Monitor



## NoBot (Oct 12, 2019)

The local power company requires a Phase Loss Monitor with lights on all 3 phase services. It would be located at the main 400 amp panel, 120/240 3º panel.
Yes, it's 120/240, not 208.
Since this is in a remote area of the building, I'd like to have an audible alarm with lights.
I was quoted $700 by the local wholesaler. That seams high.
Does anyone have a source for a better price? It would be feed by a 3 pole 20A at the main panel.


----------



## SWDweller (Dec 9, 2020)

This seems like a honey dew project to me. I am used to the POCO stating make and model to me for anything that they require. 
Another point you have a high leg service, what ever you choose to use needs to be able to handle the high leg. 
What is the function of the alarm? Knowing that there is a phase loss does not protect the equipment. 

I went looking and found one with lights. I did not look long as I stated my interpretation in the first sentence.








PH001 & PAN45-01-00 - Modular monitoring relay by AMI | DirectIndustry


The PH001 coupled with the PAN45-01-00 is the most complete set to monitor your single-phase or three-phase electrical installation, with or without neutral. The PAN45-01-00 is intended to display the information and states detected by the PH001 on the front of the cabinet in complete safety. The...




www.directindustry.com




I would be having the POCO state in writing what they want so you can approach the need with professionalism.


----------



## paulengr (Oct 8, 2017)

Super easy.

Grace Technologies





__





Voltage Indicator Learn More Page


Voltage Test Station Learn More page




www.graceport.com





Ignore all the safety stuff. It’s a 3/4” conduit mount with 4 wires and 8 lights (2/phase) for cheap. Phase lights, whatever you want them for. They blink depending on voltage.

The hassle with Grace is they have far too many products.


----------



## gpop (May 14, 2018)

NoBot said:


> The local power company requires a Phase Loss Monitor with lights on all 3 phase services. It would be located at the main 400 amp panel, 120/240 3º panel.
> Yes, it's 120/240, not 208.
> Since this is in a remote area of the building, I'd like to have an audible alarm with lights.
> I was quoted $700 by the local wholesaler. That seams high.
> Does anyone have a source for a better price? It would be feed by a 3 pole 20A at the main panel.



Are you sure they did not screw up and mean a surge suppressor with a light per phase.

Phase monitor is useless unless its designed to turn off anything in the panel that requires 3 phase. We use atc phase monitor relays and cut control power to lift station panels to protect against single phasing and reversed phase rotation. We also use a step down transformer in case poco switches the high leg position during a repair.


----------



## paulengr (Oct 8, 2017)

gpop said:


> Are you sure they did not screw up and mean a surge suppressor with a light per phase.
> 
> Phase monitor is useless unless its designed to turn off anything in the panel that requires 3 phase. We use atc phase monitor relays and cut control power to lift station panels to protect against single phasing and reversed phase rotation. We also use a step down transformer in case poco switches the high leg position during a repair.


You mean like the ones Carlo Gavazzi or Metamucil sells? That’s a bit different from just phase lights,


----------



## macmikeman (Jan 23, 2007)

I used to do a lot more commercial air conditioning jobs than these days. I would put in phase monitoring relays all the time to protect the motors from going into single phase. I think most of that is handled in the manufacturing of the bigger package units and chilling tower fans nowadays.


----------

