Monitoring 220VAC

[Mustang65]

Well, I have taken the big step!!!! I have purchased a GEM System 2 (Donut version), and it should be arriving tomorrow. Just received my shipment of DS18B20 temperature sensors this morning and a few other electronics toys. The plastic case to protect the GEM from the elements, arrives on Thursday. Here in Florida, our panels are mounted outside.

So I was looking over the documentation and had a question. The PT that is used to measure the line voltage is only connected to one of the phases. We tend to get a lot of 1/2 power outages. Yes, we lose power on only one side of the service. Can play hell on some of the equipment, but lucky for me, the AC shuts down when it only sees one phase and does not start up until they are both back in service.

So, is there an option to install a second PT and be able to monitor both phase voltages? Probably not... Wait... how about a 220 VAC PT? I would see the voltage (1/2) and could determine which phase is out, by looking at the current on the mains. PT (220VAC) used in Europe... Forget that idea....

[Teken]

Well, I have taken the big step!!!! I have purchased a GEM System 2 (Donut version), and it should be arriving tomorrow. Just received my shipment of DS18B20 temperature sensors this morning and a few other electronics toys. The plastic case to protect the GEM from the elements, arrives on Thursday. Here in Florida, our panels are mounted outside.

So I was looking over the documentation and had a question. The PT that is used to measure the line voltage is only connected to one of the phases. We tend to get a lot of 1/2 power outages. Yes, we lose power on only one side of the service. Can play hell on some of the equipment, but lucky for me, the AC shuts down when it only sees one phase and does not start up until they are both back in service.

So, is there an option to install a second PT and be able to monitor both phase voltages? Probably not... Wait... how about a 220 VAC PT? I would see the voltage (1/2) and could determine which phase is out, by looking at the current on the mains. PT (220VAC) used in Europe... Forget that idea....

Hello Don,

Brultech indeed offers a 240 VAC PT if you require it. I have both in use in my home, one is using the standard 120 VAC PT on GEM 1 and GEM 2 uses the other 240 VAC PT.

But its configured to monitor 120 VAC and measures the other electrical leg of the 120 / 240 VAC split single phase electrical system in my home.

Congratulations on the new purchase and take the time to read the entire service manual. While you wait for the hardware to arrive you can print off the last few pages in the install guide which offers a blank breaker template for you to use to document each of the CT's and what loads it monitors.

Purchase some *Ideal* 44-102 label markers to help you identify and track the CT wires in the GEM's. Also, please remember the PT can not be placed on a UPS only the PSU that powers the GEM and DB should be placed on such.

[ben]

I spoke with Paul and he says it's possible you have a loose lug given the half outages. It could be in your panel, at the meter box, or at the transformer.