Estimating KWh electicity billing using clamp-on amp meter

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Our water and electricity (and garbage, and soon to be cable/Internet) are all from the same "company". The city. ;-) ...though the water is billed separately (electricity and garbage are billed together).
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wrote

Aren't you in the MA area? That seems to be a monopoly of the monopolies. Is the city getting a cut?
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Me? Good God, man. I'm not nuts! I moved out of New England (Vermont), for good, four years ago. We live in Alabama, 100mi down the road from Dufas. ;-)

I don't think so. Everything (but water) is pretty cheap. Electricity is $.08/kWh and garbage is $15/month, both half what they're paying in Vermont. Property taxes are a quarter.
The downside is that there are a significant number of power outages. None long, just enough to be annoying. ...and no cable TV, yet (Charter did just come by, but I'm holding out for the city's "fiber to the house").
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Ed Pawlowski wrote:

I'm in Ontario, Canada.
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[ ... ]

Sometimes the "power company" does other things. In my case, they're also the water and gas companies, and handle billing for trash pickup and sewage (which is the same units as water, just a higher rate).
Gary
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Gary Heston wrote:

The city where I live owns and operates the electicity distribution utility and the water supply.
Which is going to make it tricky for the water department because most homes have been retrofitted with time-of-use electronic electricity meters which have some sort of RF wireless communications link which is supposed to act like some sort of long daisy-chain communications channel and pass all their readings through each other to collection points or nodes. Which means that the water department is going to have to hire their own meter readers when the electronic power meter network becomes operational.
I think they'll partner with the natural gas people, since they still also have to have a person come by and read the gas meters.
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Why don't they just piggyback the water meters on top of the power meters? There are no meter readers here. It's all "smart grid".
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On 5/30/2011 8:57 AM, Home Guy wrote: ...

...
Maybe he's mixing readings between meters... :)
--
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On 5/30/2011 9:13 AM, Smitty Two wrote:

The one the church here is on is computer-generated and isn't perfectly level; the algorithm adjusts for factors such as weather based on a (very) crude model that uses previous years' records for an adjustment factor to try to preclude the catch-up from being too far out. Hence, the monthlies aren't identical. OTOH, the residential level-pay plans from the same utility in town don't have the adjustment; they are flat.

Well, while OP said that early on, it wasn't clear to me that that might have been his impression as opposed to an actual observation that indeed a real meter reader did physically read the meter each and every month. So, I was surmising there could be a difference between actual and what OP thought was actual.
His later posting indicates the guy actually shows up; it's still indeterminate what he actually does since we don't have his actions on youtube to see that he only walks in, scribbles down some random set of numbers and leaves... :)

Indeed.
Still the very large outliers while others are more or less consistent just reeks of manual correction somewhere. Or, there is a phantom load that is in use on occasion that OP doesn't know about. It isn't meter creep or somesuch causing that discrepancy that is so great.
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The Kill-O-Watt meter can only measure one load at a time... It might take him weeks or months to measure all the devices using power in his office considering he has to also keep doing his actual job at the same time... An emon demon will measure all of the power flowing through an entire 3-phase panel...

That is assuming facts not in evidence... The OP has clearly stated that there is only one electrical meter locked up inside a cabinet that no one in the building has access to, only the meter reader can open it... The OP also has stated that whatever office he works in is the only occupant in the building... OP also described that the "main wires" split off into several different panels...

You install an emon demon... You then operate each circuit individually to ascertain exactly what it is that the circuit is powering... Many places that see weird energy bills often have poorly labeled circuit breaker panels and tons of "mystery switches" on the wall which no one working there knows what they control...
For there to be any vampire loads would require other tenants in the building -- the OP has not said anything about the existence of such tenants (other than to say the building he works in belongs to his employer)...

Bull... A tamperer would not have access to a utility company lock which was obviously supplied by the power company to secure the main metering enclosure cabinet...

Yup, the Kill-O-Watt can not measure hardwired loads... Only plugged in appliances... I once saw an office tenant that tried to save money by removing half the lamps from 4 lamp fluorescent fixtures and not re- lamping burnt out fixtures in a timely manner... Not re-lamping fluorescent fixtures on a predetermined schedule based on the designed life of the lamps being used is an error -- you will end up only getting 50% of the light output for the same consumption of power...

An emon demon gets wired up to a circuit breaker in the panel it is monitoring in order to sense the precise voltage on each phase... There are three sensor loops which clamp on the feeder conductors for each phase of the panel... No electronics on the basic emon demon model, its all in the little gray box...
The cost depends on what type of meter you want, the basic one just displays its reading on its face panel but there are other more advanced meters that can interface with a telephone for remote readings or integrate into a BAS system to track and graph power usage...
I remember the cost being $400 for a basic meter and upwards of $1,200 for an advanced one with all the options but it also depends on the amperage of the panel/circuit/equipment you want to monitor...

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Robert Green wrote:

I've located some PDF documents that my local utility has on-line.
I have to have a "12-month average demand" equal to or more than 50 kW, or have a 12-month rolling kwh consumption greater than 150,000 KWhrs in order to have a demand meter. 150,000 kwhrs divided by 12 is 12,500 kwh per month, which is about 4 times my average monthly consumption.
So no, I don't think I've experienced any one-time excursion into a higher rate zone, at least not in terms of being demand-metered (if indeed there are any other ways of entering a higher rate zone).
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Why are we talking about the issue of a demand meter and rates? From your previous posts, it was clear you were on the path of attempting to measure KWh usage and verify that it matches the bill. Now, I don't know what kind of bill the guys suggesting it's a rate issue have, but on my bill it clearly shows the Kwh actually used. Any billing at higher rates is then taken care of by adjusting the rate clearly on the bill.
And weren't those Kwh usage numbers from the bills that you posted already that we had?
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" snipped-for-privacy@optonline.net" wrote:

Because some people have speculated that I was on a demand meter, and that degenerated into what the typical (or actual) criteria is for a utility company to install a demand meter for a given customer.

Yes, that was on friday. Most of this discussion took place over the weekend, when there was little or no opportunity for new information to come forward.

Yes. You'd have to take up that issue with those that have been harping on the possibility that I have a demand meter.

Yes, those were the "raw" KwH numbers from previous bills. They include a 5% "adjustment factor" to cover energy lost to "line loss" - primarily in the form of heat (heating in supply wires, step-down transformers, etc) - at least that's how they define it.
The adjustment factor for residential customers is 4.1%, and I believe for commercial customers it's 5%.
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Good, that confirms what I thought. Just wanted to make sure I wasn't missing something.
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On 5/29/2011 11:53 PM, Home Guy wrote:

OK, there's at least another data point. What does the bill itself say are the rates just for confirmation that they used the same (or only fuel factors or other known rate adjustments)?
Again, does the bill actual say every month is a "real" reading or estimated or averaged/computer-generated one? That should be discernible as well. That the months that are such obvious outliers are both early in different calendar years and that the other months are more or less regular makes me think they aren't reading the meter physically on the first of every month as you think but are using a use-estimating/averaging plan w/ the annual catchup that's getting you because the average isn't high enough for the total annual use.
I'd again ask; does that same trend hold for the other four years or so since you've had the building? I'm thinking it's a good likelihood it does. What is the annual _total_ use for each year? Is that pretty consistent?
Picking up the phone and confirming that would be a start. Sending a copy of the summary statements that show the anomaly and asking for an explanation of that would be another step.
The single-month discrepancies don't jibe w/ the other ideas thrown out imo unless there's a client/renter/interloper who has a one-month-a-year fetish to run a kiln 24/7 or somesuch large (very) intermittent load.
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dpb wrote:

I will post more info on what a typical bill looks like, and whether or not I see the word "estimated" anywhere on it.
I do know that the bill is broken down into about 4 or 5 different energy rates.
IE - the first X kwh is billed at Y cents per kwh, and the next J kwh is billed at K cents per kwh, etc.
Our residential bills are similarly structured, but they have fewer tiers (maybe just 2, or 3 at most).
Let me throw this out as a new question:
How are poly-phase (in this case, 3 phase) kwh measurements made?
Is it just the sum of the individual phases, or is it the sum times some factor (ie square-root of 3) or some such?
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With a three-phase energy meter, of course, else you would have three meters.

The simple sum of the power in the three phases.
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On 5/30/2011 9:03 AM, Home Guy wrote: ...

Basically, yes. In theory it could be like three single-phase meters each connected across a phase and neutral. But, it ain't quite so easy as generally there isn't access to the N and it turns out one can show that the equivalent of connecting three to a common point ends up that one of the three can be eliminated leaving that one only needs two even for unbalanced loads.
I have vague recollections of this in power circuits 101, but that's been nearly 50 years now... :)
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It's gotta be that way, or power (energy) out <> power (energy) in. The universe gets pissed-off when that happens.
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On 5/30/2011 8:12 PM, snipped-for-privacy@att.bizzzzzzzzzzzz wrote: ...

Well, yes, that's what it is that allows as how it can be shown that only the two are needed...I was trying to smoosh over the details here on purpose of trying to not write a theme but at least brush by the route... :)
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