Still Confused - GEM Showing 46 Amps @ 240V but 5266 Watts

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G550_Pilot
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Still Confused - GEM Showing 46 Amps @ 240V but 5266 Watts

Post by G550_Pilot » Fri Aug 17, 2018 7:21 pm

OK, I think I am still confused about how the GEM and Dashboard present Watts and Amps.

In a previous POST I asked a question about how the GEM was showing watts and amps. I thought I had it figured out, but now I am (again) not so sure.

Here is the background, hopefully, someone can make it clear for me:

I have a 240V Circuit for an Electric clothes dryer. There is no neutral. I have two CTs, one on each hot leg setup as a type-b dual CT configuration. I have verified and reverified proper configuration of the CTs and the GEM previously when I had this questions. My dryer is rated at 5,500 watts and it appears to be pulling over 5,200 watts during operation:
Screen Shot 2018-08-17 at 5.01.36 PM.png
Screen Shot 2018-08-17 at 5.01.36 PM.png (51.73 KiB) Viewed 2907 times
What I cannot for the life of me (still) figure out why the GEM is reporting 46 Amps. Somewhere this number must be getting doubled. 5,266 Watts / 240v should give me about 22 amps, not 46 amps. My breaker is only a 30 amp breaker.

Where in my GEM or dashboard setup can I adjust my settings to show the correct Wattage AND amperage?
Screen Shot 2018-08-17 at 5.19.00 PM.png
Screen Shot 2018-08-17 at 5.19.00 PM.png (549.06 KiB) Viewed 2907 times
Thanks!!
ben
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Re: Still Confused - GEM Showing 46 Amps @ 240V but 5266 Wat

Post by ben » Mon Aug 20, 2018 10:31 am

Deleted my previous post and attached a document Paul created that explains how power is calculated on the GEM.

If you want the DashBox to calculate VA, you're best off leaving it as-is as VA uses the voltage reference from the GEM (which is at 120V).

If you just want the Amps to show in the 240V range:

For balanced loads, you can get the amperage at a 240V level by removing 1 CT and then applying the "Multiply by Two" setting.

For unbalanced loads, you can increase the CT Range by 1 on the channel and then turn on the "Multiply by Two" setting.
Attachments
How GEM measures power v2.pdf
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Ben
Brultech Research Inc.
E: ben(at)brultech.com
G550_Pilot
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Re: Still Confused - GEM Showing 46 Amps @ 240V but 5266 Wat

Post by G550_Pilot » Mon Aug 20, 2018 12:09 pm

Ben -

Thank you. So basically, if I am using 2 CTs on a 240V circuit, I just need to cut the Amp reading in half because the GEMs voltage reference is 120V, is that correct?
ben
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Re: Still Confused - GEM Showing 46 Amps @ 240V but 5266 Wat

Post by ben » Mon Aug 20, 2018 12:31 pm

G550_Pilot wrote:Ben -

Thank you. So basically, if I am using 2 CTs on a 240V circuit, I just need to cut the Amp reading in half because the GEMs voltage reference is 120V, is that correct?
Yeah, if you want it to log Amps at the 240V level you'll have to cut the amperage in half using one of the methods listed.
Ben
Brultech Research Inc.
E: ben(at)brultech.com
G550_Pilot
Posts: 61
Joined: Sun Apr 17, 2016 1:25 am

Re: Still Confused - GEM Showing 46 Amps @ 240V but 5266 Wat

Post by G550_Pilot » Mon Aug 20, 2018 1:25 pm

Ben -

But the watts would be correct even if the amperage is showing double, correct?
ben
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Re: Still Confused - GEM Showing 46 Amps @ 240V but 5266 Wat

Post by ben » Mon Aug 20, 2018 2:23 pm

G550_Pilot wrote:Ben -

But the watts would be correct even if the amperage is showing double, correct?
Yeah, the watts are correct.
Ben
Brultech Research Inc.
E: ben(at)brultech.com
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