Submetering

1. What is the difference between "primary metering" and "submetering"?
2. I can't understand my utility bill. What is a "kilowatt," and what is a "kilowatt hour"?
3. I understand about the Demand Charge, but what can I do about it?
4. Is submetering illegal?
5. My building is already built. Is it too late to add submetering?
6. Do I have to see my EMON meter to read it?
7. I have another question

What is the difference between "primary metering" and "submetering"?

The primary meter is installed at the building service entrance, accessible from outside the building, and is read by the utility. The primary meter reading is used for billing purposes. A submeter (also known as a "check meter) is installed on a branch circuit for the purpose of keeping track of electrical usage and/or KW demand on that branch. EMON is the nation's largest manufacturer of submeters.

I can't understand my utility bill. What is a "kilowatt," and what is a "kilowatt hour"?

Kilowatts (KW) are a unit of power, measured at one precise point in time. Residential utility customers rarely if ever have to pay for kilowatts. Electric utilities generally charge a few dollars per kilowatt (the "Demand Charge" ) on three phase service for medium-to-large customers. Here in the Pacific Northwest, this "demand charge" for larger users often constitutes one quarter to one third of the monthly bill.

Kilowatt-hours (KWH) measure the total energy consumption over a long period of time, typically one month. Every utility bill includes an energy usage charge of a few cents per KWH. For most residential customers, the KWH charge makes up virtually the whole bill.

I understand about the Demand Charge, but what can I do about it?

EMON offers an inexpensive and easy-to-install meter that records both KWH and KW. This data can be used to locate electrical loads that drive demand above acceptable levels.

For a more immediate solution, EMON's Promon style meter can be installed right at the building service entrance. An optional dry contact output signal can be configured to warn the property manager, or initiate an automatic load-shedding system, when overall building demand rises above a pre-set level.

Is submetering illegal?

There is no state or federal law against submetering. Utilities, however, do have the legal right to forbid their customers from buying energy and re-selling it at a profit.

A landlord has the legal right to ask his tenants to pay for the energy they use, as long as the landlord does not charge the tenants more than the energy actually costs. The landlord may estimate the tenant usage based on a square footage calculation or other method, or measure it more accurately by the use of submeters.

My building is already built. Is it too late to add submetering?

The standard EMON KWH and KWH/KW meters all utilize a split-core type current sensor that can be installed in place over live conductors. The sensors do not require a separate CT cabinet, and can be installed in a switchboard or panel up to 2,000 feet away from the meter.

Do I have to see my EMON meter to read it?

EMON offers an optional package of hardware and software to allow EMON meters to be read, and statements generated, automatically, from a remote location. This system can be connected to new meters, or to existing EMON meters less than ten years old. It can be hosted on a Windows XP or Windows 98 operating system.

I have another question

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