New to Metering, Installation questions

General questions and discussions focused around the EKM Metering System. Discuss your meters, installations, and meter communications here.
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deafboyzaudio
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Joined: Sat Jan 27, 2018 3:10 pm

New to Metering, Installation questions

Post by deafboyzaudio » Sat Jan 27, 2018 3:22 pm

Hello everyone,
Looking forward to ordering the omnimeter v.4 just using the plain ekm dash and a computer via usb. Will be using it in my personal house to determine what 240v single phase 60hz appliances are consuming so much power in my house and help to figure out the split of the power bill between occupants.

Have watched some videos and read some things but still have questions. I jsut have basic understanding of household power.

How does the meter determine what appliances are using what in kwh?

does it split it up into consumption on each breaker? not sure how it does this by being upstream of it all when there are 20 breakers in a house...

Or does it only monitor one at a time? is this why the 1 amp fused wires are hooked up to another breaker? is this the solitary breaker I am getting results for?

kind of confused.

thanks

Jameson
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Re: New to Metering, Installation questions

Post by Jameson » Mon Jan 29, 2018 4:11 am

Hello deafboyzaudio! Welcome to the EKM forum!

Yes, you can use our Omnimeters to accurately measure the electricity being used by each apartment. This is what is referred to as submetering.
How does the meter determine what appliances are using what in kwh?
If you want to determine the usage for a single appliance you would have to use a dedicated meter for that appliance. In the case of a meter that is installed to measure an entire apartment, our meters and our data systems will not tell you how much your stove uses vs your lights vs your dishwasher for example. This is what is called "energy disaggregation" and we are not there yet. If you were to look at the chart that is in the EKM Dash you can sometimes tell by looking at the patterns to see which loads in the apartment are being used. For example small cycling loads of a couple hundred watts could be a refrigerator, whereas longer multi-thousand watt loads could be a water heater.

Here is an example (This is an EKM Push connected meter in the EKM Widget) of what your data might look like, you can see there are patterns in the usage that could be attributed to different appliances.
Screenshot 2018-01-29 12.09.02.png
Screenshot 2018-01-29 12.09.02.png (318.88 KiB) Viewed 8192 times
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371

deafboyzaudio
Posts: 4
Joined: Sat Jan 27, 2018 3:10 pm

Re: New to Metering, Installation questions

Post by deafboyzaudio » Mon Jan 29, 2018 11:11 am

Ok so if I wanted to measure the kwh on a single breaker would I just move the cts to that individual breaker?

Jameson
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Re: New to Metering, Installation questions

Post by Jameson » Mon Jan 29, 2018 1:36 pm

Yes, if you wanted to move your meter from one electrical system (the entire breaker panel) to another electrical system (just a single breaker) you would move the CTs and potentially reconfigure the voltage reference wires.

For a 120 volt 2 wire (1 hot 1 neutral) system (like what just a single breaker would be) you would only use 1 CT like this: https://help.ekmmetering.com/support/so ... s-metering

For a 120/240 volt 3-wire (2 hots 1 neutral) system (like what your entire panel probably is) you would only use 2 CTs like this: https://help.ekmmetering.com/support/so ... v-metering
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371

deafboyzaudio
Posts: 4
Joined: Sat Jan 27, 2018 3:10 pm

Re: New to Metering, Installation questions

Post by deafboyzaudio » Tue Jan 30, 2018 11:01 am

Ok that makes as lot more sense now, thanks. The last question I have is how to hook up the voltage reference wires. From the diagram it looks like they are connected using the same wires the cts are on, upstream. Is this accurate?

These are just to measure voltage I assume?

If I did the whole house metering how do I decide which ones to use for voltage reference? There are 120 and 240 3 wire both.

Thanks a lot

Jameson
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Re: New to Metering, Installation questions

Post by Jameson » Tue Jan 30, 2018 12:04 pm

Yes, you need to connect the voltage reference wire for Line 1 to Line 1 and you need to install CT1 on Line1. The voltage reference wire for Line 1 can connect anywhere in your panel to Line1 (it does not need to be upstream or downstream of the CT)

Yes the voltage reference wires are to measure voltage and to power the meter itself. You need to follow the instructions in the help article I sent you in my previous post to have a good installation.
If I did the whole house metering how do I decide which ones to use for voltage reference? There are 120 and 240 3 wire both.
In the USA we have 3 wires delivered to a residence. 2 wires are hot and 1 wire is Neutral. If you use a multimeter to measure from either of the hot wires to neutral you will measure ~120 volts. If you measure from hot wire to hot wire you will get ~240 volts. You can designate either of the hot wires to be Line1, the other hot wire would then be Line2.
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371

deafboyzaudio
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Joined: Sat Jan 27, 2018 3:10 pm

Re: New to Metering, Installation questions

Post by deafboyzaudio » Thu Feb 08, 2018 11:42 pm

Ok thanks. Got the meter a couple days ago and looking to hook it up tonight. One last last question I havent seen in documentation anywhere for sure... Can i hook up multiple current transformer sets to the meter and log data separately? or would i need another whole meter for this?

Jameson
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Re: New to Metering, Installation questions

Post by Jameson » Fri Feb 09, 2018 3:35 am

I would say it depends on what you are trying to do:

If you want to get 4 separate kWh values from your electrical panel, treat these as 4 separate systems and use 4 separate kWh meters.


If you want to keep track of each phase separately, the EKM Omnimeter will measure and report volts, amps, watts, and power factor on each line (each phase). So you can use this to monitor each phase separately. Depending on your electrical system you will use 1,2 or 3 of the Omnimeters CT inputs: https://help.ekmmetering.com/support/so ... 6000200176


If you want to use multiple CTs on each phase, you can connect multiple Current Transformers to each of the 3 CT inputs on an Omnimeter, but these CTs will be cumulative. For example you can connect 4 CTs in parallel to CT Input Line1, if you have 20 amps going through each CT, the meter will register 80 amps amps on Line1.

Please Note: if you are using 4 x 200 amp CTs on Line1, the cumulative measured value of the 4 CTs should not exceed 200 amps.
Jameson
EKM METERING
http://www.ekmmetering.com
831.425.7371

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