I was hired to replace all the lighting in a fire station with high efficiency lighting and motion detectors. The fire chief explained to me that the electric bill was averaging $700 a month and hoped upgrading to high efficiency fixtures an bulbs along with motion sensors would lower the bill. I thought the $700 bill per month sounded very high considering they mostly just watch tv to pass away the down time. The chief believed the lighting was the main culprit considering the lights were left on more than turned off. Now it has been 3 months and the chief gave me an update. He said the bill had gone down slightly but something else must be driving the bill sky high. I suspected the bill would not drop dramatically but would like to solve this puzzle and plan to offer some free consulting to the chief to help him figure out the problem. (yes the chiefs under the gun with a shrinking budget)
Besides a tv that pretty much never gets turned off, the rest of the basics like a microwave, electric stove, 2 fridges, ect,, most of whats being used would be comparable to a residential home .
Here is what I discovered upon further investigating and need some advice.
The service is 240 3 phase. A phase and B phase feed a couple sub panels which supply electric to all the 120/240 devices in the building. the 240v 3 phase only feeds an air pack system (to refill oxygen tanks) and 3 phase also feeds a 240v commercial sized dryer. The chief told me that the air pack system is only used 2 or 3 times a month and the dryer may be used by a handfull of fireman who dry their fireproof gear after a fire and a few of the guys wash their work uniforms at the station while the majority take their laundry home to wash and dry. (so 3 phase loads are rare)
SO I know this is a lot of ambiguous information but in a nutshell the $700 electric bill a month seems like it's twice as high as it should be. This is a small town fire station btw. 6 to 8 fireman per 24 hour shift.
I've taken Mike Holts 14 week instructional class (6 weeks electron theory, 8 weeks preparing for master exam) and I have just bought his dvd series. I'm still learning , I come to this forum often to help me make sense of things that haven't clicked yet despite the excellent class I took and the dvds I watch. Unbalanced loads still baffle me. I think the A and B phase electrons are canceling each other out on the 240 single phase loads but the C phase without a load confuses me. I think those electrons return to the source via the neutral.... or with 0 amps , since there is no load ,maybe the service acts as a single phase system 180 degrees (when zero amps on c phase) ???? . I'm unsure how this effects the kwh or does it? Does this cause a power factor issue? Is the service acting as an open delta 95% of the time???
anyway.......
I plan to return and do a load calculation which would give me numbers to play with and I know 99% of you reading this would like some numbers now. (I've read a lot of threads on this forum lol).
Here is my question.
Would the manner in which the main service panel has been split, using 2 phases to supply virtually all the power being used daily..... And then the 3 phase just powering rarely used devices .... be the prime suspect here for the high bill. I obviously recognize that the service is very unbalanced and I would have never split it up like it is, but -
what effect would you expect that this setup would play on the electric bill? or would it :-?
Just asking for general advice right now without providing you guys with numbers to crunch at this time.
Best guesses and theories will be appreciated!
what say you?
Thanks
Ben
Besides a tv that pretty much never gets turned off, the rest of the basics like a microwave, electric stove, 2 fridges, ect,, most of whats being used would be comparable to a residential home .
Here is what I discovered upon further investigating and need some advice.
The service is 240 3 phase. A phase and B phase feed a couple sub panels which supply electric to all the 120/240 devices in the building. the 240v 3 phase only feeds an air pack system (to refill oxygen tanks) and 3 phase also feeds a 240v commercial sized dryer. The chief told me that the air pack system is only used 2 or 3 times a month and the dryer may be used by a handfull of fireman who dry their fireproof gear after a fire and a few of the guys wash their work uniforms at the station while the majority take their laundry home to wash and dry. (so 3 phase loads are rare)
SO I know this is a lot of ambiguous information but in a nutshell the $700 electric bill a month seems like it's twice as high as it should be. This is a small town fire station btw. 6 to 8 fireman per 24 hour shift.
I've taken Mike Holts 14 week instructional class (6 weeks electron theory, 8 weeks preparing for master exam) and I have just bought his dvd series. I'm still learning , I come to this forum often to help me make sense of things that haven't clicked yet despite the excellent class I took and the dvds I watch. Unbalanced loads still baffle me. I think the A and B phase electrons are canceling each other out on the 240 single phase loads but the C phase without a load confuses me. I think those electrons return to the source via the neutral.... or with 0 amps , since there is no load ,maybe the service acts as a single phase system 180 degrees (when zero amps on c phase) ???? . I'm unsure how this effects the kwh or does it? Does this cause a power factor issue? Is the service acting as an open delta 95% of the time???
anyway.......
I plan to return and do a load calculation which would give me numbers to play with and I know 99% of you reading this would like some numbers now. (I've read a lot of threads on this forum lol).
Here is my question.
Would the manner in which the main service panel has been split, using 2 phases to supply virtually all the power being used daily..... And then the 3 phase just powering rarely used devices .... be the prime suspect here for the high bill. I obviously recognize that the service is very unbalanced and I would have never split it up like it is, but -
what effect would you expect that this setup would play on the electric bill? or would it :-?
Just asking for general advice right now without providing you guys with numbers to crunch at this time.
Best guesses and theories will be appreciated!
what say you?
Thanks
Ben