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Meter Multiplier

Nmaac1

Member
Location
New York
Occupation
Office Assistant
I have a smart meter that was installed at my house prior to us moving in. This seems to be a meter that would be used at a large business that consumes a large amount of electricity. We have a meter multiplier of 40 on this and are questioning if this would be correct? Our usage is double from our previous home which was bigger.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
The house size may not be a factor. The problem could be the heating system. Did one home have gas and the other electric? If you have the same requirements on all appliances then you may have an issue,
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Smart meters are becoming the norm even for single family dwellings. Most utility companies will come out and check the meter for accuracy. The only way to know for sure is to have a comparison to the bills using the old meter.
 

TheRiverStyx

New User
Location
Washington
Occupation
Journeyman Meterman
I have a smart meter that was installed at my house prior to us moving in. This seems to be a meter that would be used at a large business that consumes a large amount of electricity. We have a meter multiplier of 40 on this and are questioning if this would be correct? Our usage is double from our previous home which was bigger.
If the meter has a multiplier it is an instrument rated meter meaning it should be wired to CT's, there should be a CT can that houses the CT's somewhat close to the meter base and sealed by the utility company as this is for their use only even if it is located inside your home, for residential services that have these these they would be typically installed on 400+ amp rated services, The house size, neighbor comparisons etc... are not at all very good indicators of what you should expect your usage to be, the same size house with a heat pump and gas furnace will use much less than the same with heat pump and electric air handler and a thousand other items can cause usage to be drastically different, I would call your utility and request a meter test but I would not expect your meter to be out of accuracy, the majority of meter manufactures build a residential meter to be accurate to within +-0.2% across the rated class of the meter, and the majority of the states allow a +-2% variance of the meters accuracy when tested. From my experience most meters test between 99.90% and 100.10% far within the allowable range to most regulatory bodies. the CT's should also be tested to make sure they are accurate but also to make sure they have the correct billing ratio. with a multiplier of 40 the CT's installed should be rated for 200:5 meaning for every 40 amps drawn on your service the meter will see 1 amp, this in turn also means that for every 40kwh you use the meter registers 1kwh, you will see on your bill that the readings on the meter are then multiplied by 40 to reach the usage to be billed.
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
I have a smart meter that was installed at my house prior to us moving in. This seems to be a meter that would be used at a large business that consumes a large amount of electricity. We have a meter multiplier of 40 on this and are questioning if this would be correct? Our usage is double from our previous home which was bigger.
Generally speaking, meter multipliers arent used on houses less than 500 amps because a self contained 2S class 320 will meter correctly. See if your says FM3S on it. Is it mounted to the side of a large CT cabinet? Or, does it look like a normal meter base seen on 99% of the houses around. Form 3S meters are used on single phase CT installations.
 

Nmaac1

Member
Location
New York
Occupation
Office Assistant
The house size may not be a factor. The problem could be the heating system. Did one home have gas and the other electric? If you have the same requirements on all appliances then you may have an issue,
We live in the country and only have electricity for our home, our house is heated by Fuel oil.
 
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