Unbalance Current Detection
Unbalance Current Detection
(OP)
I am looking for a meter to detect unbalanced current. This means if one phase current is more than 10% in difference with other two ,the unit initiates a trip.
I also have one set of CT's which are source for Crompton Ammeters. There is diagram for connecting two meters in series, is this going to be accepotabel and provide enough current for proposed meters. I apprecite any feedback on this.
I also have one set of CT's which are source for Crompton Ammeters. There is diagram for connecting two meters in series, is this going to be accepotabel and provide enough current for proposed meters. I apprecite any feedback on this.






RE: Unbalance Current Detection
RE: Unbalance Current Detection
While I am not sure of this, you may want to look up some highend Power quality meter from leading switchgear mfr like SQ D, GE, Eaton etc. to see if they include such a functionality.
RE: Unbalance Current Detection
RE: Unbalance Current Detection
There is no easy way to do this with conventional meters. A digital power meter of some kind is probably your best option.
You may need to extract the current data and calculate the imbalance in a computer or PLC.
For inexpensive, I'd take a look at meters from Electro Industries, such as the "Shark" meter.
RE: Unbalance Current Detection
RE: Unbalance Current Detection
For industrial applications I would look into the Basler 200 and 300 series relays. These are not quite utility standard, but should be priced such.
For a utility application, spend the money needed.
What is unbalance? Negative sequence? Zero sequence? What is the application?
RE: Unbalance Current Detection
I don't think that power meter is good solution for the protection. As posted above, you can use very simple relay:
motor protection or broken conductor detection.
Regards.
Slava
RE: Unbalance Current Detection
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Unbalance Current Detection
Most other relays do not detect the unbalanced for current difference less than %40.00.
My budget is around $500-$700.
I would call 10-20% current imbalance.
does anybody know any other manufacturer I can check?
RE: Unbalance Current Detection
What and why are you protecting? It does make a difference to the solution to the problem.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Unbalance Current Detection
Try http://startco.ca/
Best Regards.
Slava
RE: Unbalance Current Detection
Warros, your suggestion might work, although I prefer using a unit with adjustable settings.
I called Startco, they dont have a unit I am looking for.
RE: Unbalance Current Detection
As Bill implied, if there were a cheap method someone would be selling it by now. There is a reason why this is not a commnly applied protection on small installations: the cost is not justified.
You are the only judge as to what is justified. Anything you will build will require current sensing and a sort of a meter/comparator and decision maker and it can't possibly cost you within the range you specified in the USA.
RE: Unbalance Current Detection
RE: Unbalance Current Detection
RE: Unbalance Current Detection
RE: Unbalance Current Detection
RE: Unbalance Current Detection
Please see attached
http:/
for my pinion you can found this relay in US.
Best Regards
Slava
RE: Unbalance Current Detection
The refrigeration industry uses protectors with similar features. About 1/10th the cost. Several manufacturers to choose from.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Unbalance Current Detection
http://www.ssac.com/standard/ff-mp2.htm
I am used to nits similar to the WVM series.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Unbalance Current Detection
I know
For this issue, I hope enough attached
http:/
Regards.
Slava
RE: Unbalance Current Detection
Regards.
Slava
RE: Unbalance Current Detection
These are all based on voltage sensing concept.
slavag : That company doesnt have any sensor.
I sourced out BE1-700C it has 46 element.I wish I could find a single element relay out there that does my requirment.
RE: Unbalance Current Detection
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Unbalance Current Detection
RE: Unbalance Current Detection
Question is that how heat could affect the resistor performance and overall accuracy of the setup?
RE: Unbalance Current Detection
Bill
--------------------
"Why not the best?"
Jimmy Carter