Questions? Contact Us Now +1 (303) 772-6100

Automation &
Monitoring Solutions.

Using a Quality Split Core Current Transformer for Submetering Work

Centralized power may be a good thing but there are times when people using a facility must shoulder part of the responsibility and obligations, which are mostly made possible by submetering. An August, 2010 article in The Electricity Forum states as much about an apartment complex in New York City’s Greenwich Village:

Another resident of the 160-unit building, on Seventh Avenue between 13th and 14th Streets, says he leaves the air-conditioning on when he goes to work, when he sleeps at his girlfriend’s apartment, even when he leaves the country on vacation — and only partly out of sympathy for his cat, Kitty.

“My A.C. is pretty much running 24/7,” Kitty’s owner, Michael Perlo, a 28-year-old television producer, said with more bravado than guilt. “Not having to pay for electricity makes me a little bit more reckless.”

Mr. Perlo and his neighbors live in a building where not just heat and hot water, but electricity, is part of their monthly rent — a more-common-than-you’d-think arrangement caused by old-fashioned wiring in which a building has a single “master meter” tracking power use rather than individual meters tied to each tenant. They can blast their air-conditioners all summer long without paying a dollar extra.

In an age of environmental consciousness, it’s easy to overlook the consequences of leaving the power on all day even when nobody’s home. As such, you must act to curtail the unnecessary power usage and figure out where savings are possible. Installing a split core current transformer (CT) like those sold by Aim Dynamics can be a step in that direction.

Split-core CTs are small devices designed to measure the current flow of a primary conduit without having to rewire. The device’s centerpiece is a magnetic core wrapped with thousands of secondary windings. The output is typically a low current or low voltage. Mounting harnesses are sometimes set up after attaching the transformer over the conducting wire. However, most units work perfectly fine by simply dangling from the primary conductor.

A submetering installation involves setting up the split core current sensors on each power line that leads to the units. Instead of just having a master meter each unit will then have its own meter fed by the split core CTs that were installed. However, all corresponding circuits must be from the same voltage source and certain wire gauges may require an extra split core current sensor.

Submetering programs for centralized facilities can carry ample utility savings for managers. An Upper East Side property manager said one of two buildings he runs reaps an extra $52,000 in power costs a year because it had a master meter.

(Source: Submetering ends reckless energy waste, The Electricity Forum)