Commercial vs Residential GEM?

Ask questions about the GEM here.
Post Reply
vespaman
Posts: 68
Joined: Sat Oct 08, 2011 2:48 am
Location: Sweden

Commercial vs Residential GEM?

Post by vespaman » Sat Apr 22, 2017 7:35 am

Looking at adding another GEM, since all channels are used up on my old (2013) GEM.
Now, it looks like there are two versions of GEM, where one is specified to work with three phases, whereas the residential is not.
I guess this means that I need the commercial version? Sounds expensive. :cry:
(Where I am at, all houses uses 230V 3 phases, only apartments has single phases)

Did I understand this correctly, and if so, what would be the price for a commercial GEM with ethernet interface?

Thanks,
Micael
Teken
Posts: 2700
Joined: Wed Dec 15, 2010 4:09 pm
Location: The Bad Lands

Re: Commercial vs Residential GEM?

Post by Teken » Sat Apr 22, 2017 8:34 am

Hello Micael,

The only difference between the commercial vs residential is the use of a 3 phase harness kit as far as I am aware. Send in a request to the sales department to confirm the costs.
Teken . . .

My ongoing projects thread: http://www.brultech.com/community/viewt ... ?f=2&t=929
Buy me a cup of coffee: https://www.paypal.me/Teken https://gfinotify.com/ Discount Code: PC10
vespaman
Posts: 68
Joined: Sat Oct 08, 2011 2:48 am
Location: Sweden

Re: Commercial vs Residential GEM?

Post by vespaman » Sat Apr 22, 2017 8:43 am

What is that (the three phase harness kit)?

I don't have this on my old GEM, I just have normal CT's and program which phase they reside on...
Teken
Posts: 2700
Joined: Wed Dec 15, 2010 4:09 pm
Location: The Bad Lands

Re: Commercial vs Residential GEM?

Post by Teken » Sat Apr 22, 2017 8:56 am

Going off memory it was a modified PT (Potential Transformer) that had the ability to monitor all three legs of the electrical phases. If your GEM is set up to monitor three phase what does the PT look like and how is it hooked up to monitor all three phases?
Teken . . .

My ongoing projects thread: http://www.brultech.com/community/viewt ... ?f=2&t=929
Buy me a cup of coffee: https://www.paypal.me/Teken https://gfinotify.com/ Discount Code: PC10
vespaman
Posts: 68
Joined: Sat Oct 08, 2011 2:48 am
Location: Sweden

Re: Commercial vs Residential GEM?

Post by vespaman » Sat Apr 22, 2017 9:03 am

It is a single PT off one phase. Apparently there's some magic going on to resolve the voltage on the other two phases from this and the current run through the other phases. (All from Ben, I never understood how it actually worked).
Teken
Posts: 2700
Joined: Wed Dec 15, 2010 4:09 pm
Location: The Bad Lands

Re: Commercial vs Residential GEM?

Post by Teken » Sat Apr 22, 2017 9:13 am

vespaman wrote:It is a single PT off one phase. Apparently there's some magic going on to resolve the voltage on the other two phases from this and the current run through the other phases. (All from Ben, I never understood how it actually worked).
Hrmm, that's interesting as this is like the 240 VAC doubling feature they use for balanced 240 VAC loads to save on CT's. I would have to gather if the system has operated fine using software to operate in 3 phase mode.

You need only purchase the exact same GEM hardware and forgo the extra expense.

In the past when 3 phase was discussed the special harness was noted by Ben. I have to gather it looks like the one I received but for 120 / 240 use. I would assume it would be spec'd for 120 / 208 for North America light commercial and 277 / 480 for high voltage commercial applications.
Teken . . .

My ongoing projects thread: http://www.brultech.com/community/viewt ... ?f=2&t=929
Buy me a cup of coffee: https://www.paypal.me/Teken https://gfinotify.com/ Discount Code: PC10
vespaman
Posts: 68
Joined: Sat Oct 08, 2011 2:48 am
Location: Sweden

Re: Commercial vs Residential GEM?

Post by vespaman » Sat Apr 22, 2017 9:56 am

Maybe Ben can chime in, it would be useful to know. I don't think there was a specific 3 phase version in 2013? But maybe I have forgotten, it was some years ago... :D

Or maybe it has to do with what kind of three phase system (we have TN over here, 400V between the phases).
ben
Site Admin
Posts: 4254
Joined: Fri Jun 04, 2010 9:39 am

Re: Commercial vs Residential GEM?

Post by ben » Mon Apr 24, 2017 9:21 am

vespaman wrote:Maybe Ben can chime in, it would be useful to know. I don't think there was a specific 3 phase version in 2013? But maybe I have forgotten, it was some years ago... :D

Or maybe it has to do with what kind of three phase system (we have TN over here, 400V between the phases).
In 2013 there wasn't a specific 3-phase version, correct. 3-phase now requires a package that comes along with the GEM including a special high-accuracy PT.

We still only support 3-phase Wye still.

Send an email to Tammy with what you're looking for (sales(at)brultech.com) and she'll get you a quote together.
Ben
Brultech Research Inc.
E: ben(at)brultech.com
vespaman
Posts: 68
Joined: Sat Oct 08, 2011 2:48 am
Location: Sweden

Re: Commercial vs Residential GEM?

Post by vespaman » Sat Jul 22, 2017 12:49 am

ben wrote:
vespaman wrote:Maybe Ben can chime in, it would be useful to know. I don't think there was a specific 3 phase version in 2013? But maybe I have forgotten, it was some years ago... :D

Or maybe it has to do with what kind of three phase system (we have TN over here, 400V between the phases).
In 2013 there wasn't a specific 3-phase version, correct. 3-phase now requires a package that comes along with the GEM including a special high-accuracy PT.

We still only support 3-phase Wye still.

Send an email to Tammy with what you're looking for (sales(at)brultech.com) and she'll get you a quote together.
So, does this mean that the new 3phase kit gives better accuracy, and if so, is the kit available as a retrofit/upgrade to us older 3-phase users?


Or is there some way of using this new kit for both GEM's (that would be the best of course, since space is getting sparse) ?

And finally, reading on the product page, it says

Code: Select all

Supports 120V/208V four wire wye (Y) systems
but does it, in reality, also support 230/400V four wire Y aswell?
ben
Site Admin
Posts: 4254
Joined: Fri Jun 04, 2010 9:39 am

Re: Commercial vs Residential GEM?

Post by ben » Mon Jul 24, 2017 10:21 am

vespaman wrote:
ben wrote:
vespaman wrote:Maybe Ben can chime in, it would be useful to know. I don't think there was a specific 3 phase version in 2013? But maybe I have forgotten, it was some years ago... :D

Or maybe it has to do with what kind of three phase system (we have TN over here, 400V between the phases).
In 2013 there wasn't a specific 3-phase version, correct. 3-phase now requires a package that comes along with the GEM including a special high-accuracy PT.

We still only support 3-phase Wye still.

Send an email to Tammy with what you're looking for (sales(at)brultech.com) and she'll get you a quote together.
So, does this mean that the new 3phase kit gives better accuracy, and if so, is the kit available as a retrofit/upgrade to us older 3-phase users?


Or is there some way of using this new kit for both GEM's (that would be the best of course, since space is getting sparse) ?

And finally, reading on the product page, it says

Code: Select all

Supports 120V/208V four wire wye (Y) systems
but does it, in reality, also support 230/400V four wire Y aswell?
Yeah, the PT in the 3-phase kit is higher accuracy. The old GEMs don't need to be retrofitted if they're working fine.

Yeah, you just need to make sure all the CTs you order are the "-i" versions as they have leads good up to 600V.

Send me an email (ben(at)brultech.com), we can probably work something out given you're a repeat customer.
Ben
Brultech Research Inc.
E: ben(at)brultech.com
Post Reply