"Smart Meter" Western Mich?

[gar]

130817-0829 EDT

In Western Michigan (Consumers Power) what is the brand and model number of smart meter that is being used for residential service?

If the meter is an Itron, then:

1. Is the the scaling factor 1.0 Kh? Any idea what Kh means?

If it were Wh, then it would make sense. On DTE meters I have seen 1.0 Kh, and 10 Kh. On the normal residential meter the 1.0 Kh is present and each step of the dot sequence is 1 Wh, on some commericial meters with 10 kH each step is 10 Wh.

2. Is the display a single digital section quantized to 1 kWh, with an area below the 004 sequence number having a sequencing of square dots, triangle, and blank for fine Wh resolution?

3. What on-line graphical data is provided at the power company (Consumers) website?

4. If you have one of these meters, then what is your typical average sleep time base load power usage?

Last winter with with gas heat, water heater, and range top, one refrigerator, two freezers, and miscellaneous competers and other small loads on all the time my base load was about 825 W, in the spring about 650 W, and now with one freezer and some other items off I am in the range of 300 to 400 W. The only gas item using electricity is the furnace and it is about 200 W average.

.

 

[meternerd]

130817-0829 EDT

In Western Michigan (Consumers Power) what is the brand and model number of smart meter that is being used for residential service?

If the meter is an Itron, then:

1. Is the the scaling factor 1.0 Kh? Any idea what Kh means?

If it were Wh, then it would make sense. On DTE meters I have seen 1.0 Kh, and 10 Kh. On the normal residential meter the 1.0 Kh is present and each step of the dot sequence is 1 Wh, on some commericial meters with 10 kH each step is 10 Wh.

2. Is the display a single digital section quantized to 1 kWh, with an area below the 004 sequence number having a sequencing of square dots, triangle, and blank for fine Wh resolution?

3. What on-line graphical data is provided at the power company (Consumers) website?

4. If you have one of these meters, then what is your typical average sleep time base load power usage?

Last winter with with gas heat, water heater, and range top, one refrigerator, two freezers, and miscellaneous competers and other small loads on all the time my base load was about 825 W, in the spring about 650 W, and now with one freezer and some other items off I am in the range of 300 to 400 W. The only gas item using electricity is the furnace and it is about 200 W average.

.

I can answer some of the questions. Kh is the Watthour constant. Watthours per revolution. On mechanical meters (usually 7.2 Kh), it's how many Watthours are used per disc revolution. On electronic meters, the "sequencing square dots" is called a disc emulator, and it's just a graphic display of the direction of power flow. To the right is forward, to the left is reverse. One complete sequence is one revolution. With a 1.0 Kh, the "disc" has to rotate 1,000 times to equal one Kwh.

 

[gar]

130823-0947 EDT

meternerd:

Thank you for the information.

My experiments indicate that each dot step on our Itron meters with the scale factor of 1.0 Kh are equal to 1 Wh, and on the meters labeled 10 Kh each step is 10 Wh.

The letters Kh are confusing. The K alone on the 1.0 Kh would make sense as the number of single dots steps to equal 1 step on the kWh digital display. Bringing hours into the scale factor, as implied by h, does not make sense.

On the 10 Kh meters I have to determine if the digital display increments by 1 kWh or 10 kWh. But I do know that 1 dot step is 10 Wh. In other words the 10 Kh meter dot sequence is 1/10 the speed of the 1 Kh meter with the same constant power load.

.

 

[GoldDigger]

The letters Kh are confusing. The K alone on the 1.0 Kh would make sense as the number of single dots steps to equal 1 step on the kWh digital display. Bringing hours into the scale factor, as implied by h, does not make sense.

Possible explanation is that K is traditionally used in math and science for a calibration constant ("Konstant" in German) rather then just meaning a factor of 1000.
In that case the print form would be something like K_h meaning the constant for the hours factor, rather than Kh.
All in all, I would have to chalk it up to "tradition" unless somebody else can provide a better explanation.

 

[meternerd]

[The letters Kh are confusing. The K alone on the 1.0 Kh would make sense as the number of single dots steps to equal 1 step on the kWh digital display. Bringing hours into the scale factor, as implied by h, does not make sense.]

Sorry if I confused the situation. By sequence, I meant On to Off and back to On. Kh merely means the amount of energy used (measured in WattHours) per pulse or revolution. Energy is Watts X Tme. If you use 1000 watts for an hour, your energy will total 1000 watthours or one Kilowatthour. Use 2000 watts for half an hour, one KWh. The utility bills are based on total KWh. Use more watts per hour or watts for a longer time, your bill goes up. Most are around 15 cents per Kwh. Still pretty cheap, considering. Just consider it like a garden hose and a bucket. In the electric utility world, KW is gallons per hour (known as demand) and KWh is total gallons (known as consumption or energy). I'm really not trying to "talk down" to anyone, just trying to make it clearer.

Now why we still bill for KWH instead of KVAH (so we could ignore power factor) is a whole other subject.

 

[GoldDigger]

Now why we still bill for KWH instead of KVAH (so we could ignore power factor) is a whole other subject.

The answer to that is incredibly simple:

Each kWh costs money to produce. The entire excess of kVAh over kWh is free, except for transport, since it delivers no net energy.

 

[mivey]

On electronic meters, the "sequencing square dots" is called a disc emulator, and it's just a graphic display of the direction of power flow.

Not only the direction but quantity as well. This is a load emulator and not a disk emulator in the traditional sense because a complete set of state changes represents 6 Kh not 1 Kh. Segment progression right = delivered, Segment progression left = received.

To the right is forward, to the left is reverse. One complete sequence is one revolution. With a 1.0 Kh, the "disc" has to rotate 1,000 times to equal one Kwh.

First, it is kWh not Kwh. The capital K indicates a constant and the lower case k represents kilo. We have kW, kWh, kvar, kVA.

Kh is the watthour constant. The h here is really like a subscript and in fact we also have K_H used for the watthour constant.

Each segment pulse is a Kh quantity so does not act like a classic disk emulator like the GE meters. This is a six state display with 4 segments but only three are used for a given energy direction. The segments are: left arrow, square, square, right arrow.

For the states, let * be unused, 0 be hollow (white), and 1 be filled (black). Consider the case where Kh = 1 Wh. For energy delivered we have the state progression as:
*000 = 0 Wh d
*100 = 1 Wh d
*110 = 2 Wh d
*111 = 3 Wh d
*011 = 4 Wh d
*001 = 5 Wh d
*000 = 6 Wh d

For energy received we have the state progression as:
000* = 0 Wh r
001* = 1 Wh r
011* = 2 Wh r
111* = 3 Wh r
110* = 4 Wh r
100* = 5 Wh r
000* = 6 Wh r

This is different from the GE meters where the display is a realistic disk emulator as I detailed here:
http://forums.mikeholt.com/showthread.php?t=149005&p=1439479#post1439479

 

[mivey]

Each kWh costs money to produce. The entire excess of kVAh over kWh is free, except for transport, since it delivers no net energy.

Don't forget the other losses at the generation point as well as the associated equipment cost. It ain't free.

 

[gar]

130823-1159 EDT

GoldDigger and mivey:

The description of h being a subscript helps. But why not just label the meter as K = 1.0 Wh or 10 Wh, and then it would be self evident?

mivey what is your brand of meter? Since the dot sequence is slightly different than our Itrons.

For those readers with the Itron type of meter labeled with 1 Kh the equation for average power over the time period of measurement is

Pave = 3.6/T

where Pave is in kW, and
T = the time is seconds for one dot step.

If you counted 6 dot steps in 20.3 seconds, then there are are 3.383 seconds per dot step and the average power over the 20.3 seconds measurement time is 1.064 kW.

If the scale factor was 10 Kh, then change 3.6 to 36 and the average power in the above example would be 10.64 kW.

.

 

[mivey]

But why not just label the meter as K = 1.0 Wh or 10 Wh, and then it would be self evident?

Because there are other meter constants that also use "K" as the first letter.

mivey what is your brand of meter? Since the dot sequence is slightly different than our Itrons.

IIRC, the example is for Itron's Sentinal and Centron meters. What particular Itron meter are you talking about?

 

[mivey]

IIRC, the example is for Itron's Sentinal and Centron meters. What particular Itron meter are you talking about?

I looked and the Itron smartmeter offering appears to be a Centron. There are different display versions and the C1SD, C1ST, C1SL are like I described before with the segments in the lower left corner of the display. The C1SR and C1SC have a display with 3 square segments in the lower right hand corner but it works essentially the same way.

For the states, let 0 be hollow (white), and 1 be filled (black). Consider the case where Kh = 1 Wh. For energy delivered we have the state progression as:
000 = 0 Wh d
100 = 1 Wh d
110 = 2 Wh d
111 = 3 Wh d
011 = 4 Wh d
001 = 5 Wh d
000 = 6 Wh d

For energy received we have the state progression as:
000 = 0 Wh r
001 = 1 Wh r
011 = 2 Wh r
111 = 3 Wh r
110 = 4 Wh r
100 = 5 Wh r
000 = 6 Wh r

 

[gar]

130824-0838 EDT

mivey:

The information on my meter face is:

Top - Centron
Center row - CL200 240 V 3 W Type C2S0D 30 TA 1.0 Kh
Vertically on right - CA 0.5, FM2S, 60 Hz

On the LCD display "kW h", note the space, is displayed below the kWh value when it is displayed.

When you watch the meter long enough there is a sequence point when 120 240 277 480 is displayed on the LCD at the lower left. What is the meaning of this?

My meter sequence consists of two square dots and a triangular dot. Corresponding from left to right with your 3 binary digits.

More clearly the Kh constant is better described as
K_h = 1.0 Wh/dot step and in the spinning disk it is per revolution of the disk instead of per step.

Confusion on Kh results from a non-intuitive presentation and lack of a corresponding definition.

At our power company you can not talk directly with someone that knows anything. Your question gets passed up the line and the response then gets passed back down. When I originally inquired about what 1 dot step equaled the response was 1 kWh. That was quite obviously nonsense because of the visual rate of change of dots. From Itron I finally found out 1 step was 1 Wh, but getting that information was not easy. Somewhere along the communication path at DTE 1 Wh got changed to 1 kWh.

.

 

[meternerd]

130824-0838 EDT

mivey:

The information on my meter face is:

Top - Centron
Center row - CL200 240 V 3 W Type C2S0D 30 TA 1.0 Kh
Vertically on right - CA 0.5, FM2S, 60 Hz




My meter sequence consists of two square dots and a triangular dot. Corresponding from left to right with your 3 binary digits.

More clearly the Kh constant is better described as
K_h = 1.0 Wh/dot step and in the spinning disk it is per revolution of the disk instead of per step.

Confusion on Kh results from a non-intuitive presentation and lack of a corresponding definition.

Oh...never had one of that type. Honestly, though, utilities don't really pay much attention to the display indicators. I usually only look at 'em when I test and reset a meter prior to installation. Meters are tested using optical pickups that look at the infrared pulses coming from the clear plastic light tube in the top of the inner cover (at least on Centron meters).


[When you watch the meter long enough there is a sequence point when 120 240 277 480 is displayed on the LCD at the lower left. What is the meaning of this?]

Once every display cycle, the display does a segment test to let you see that all of the LCD segments are working. Otherwise a 9 could really be an 8 with the lower left segment missing, etc. Many meters automatically detect nominal service voltage and display it. Itron uses the same display module on many different meters, and not all of the available segments are enabled.

[On the LCD display "kW h", note the space, is displayed below the kWh value when it is displayed.]

That segment is probably able to say kW h or kVAh and they just program it to only show the segments they want. Well....good a guess as any


One other issue utilities now face is that most of us no longer read meters manually. Now we read by radio or some other technology. So a meter that has a display or seal problem can go undetected for a long time. Glad I'm almost retired!

 

[mivey]

On the LCD display "kW h", note the space, is displayed below the kWh value when it is displayed.

The space is because of the multiple display options. Normally characters are ordered as CCUMPFMKWVARh and are turned on/off as needed to indicate the item displayed.

When you watch the meter long enough there is a sequence point when 120 240 277 480 is displayed on the LCD at the lower left. What is the meaning of this?

If you see them all, it is during a display segment test. Normally only the closest nominal voltage is displayed but I think this is active for polyphase meters only.

My meter sequence consists of two square dots and a triangular dot. Corresponding from left to right with your 3 binary digits.

Think of the triangles as left and right arrows as described in my other post. This is the 4 dot display with only either the left or right arrow being displayed depending on the direction of energy flow (which results in the 3 dot display sequence I showed in the example).

There are two other arrows (triangles): up and down. For polyphase meters these show the power factor (up = lagging, down = leading). You should be able to see these during the display segment check. There is a VA, VB, and VC also. I don't believe the disk emulator displays during the segment check (probably to avoid confusion).

If you see an embossed magnet symbol in the face, this is where you can touch and remove a magnet to scroll through display items. Hold the magnet for about 5 seconds to switch display modes (there may or may not be alternate modes programmed and it will time out back to normal after the programmed delay). Also hold the magnet to activate scroll lock (ScrLoc is displayed). If there is no embossed magnet in the face (usually lower left), the touch point is either in the 9 or 10 o'clock position (if there is a magnet switch at all).

 

[gar]

130824-1518 EDT

mivey:

Thank you. Very good. I don't have any generation, and thus the left arrow does not appear.

.

 

[gar]

130828-0944 EDT

I have now converged on describing the average power equation as:

P[SUB]ave[/SUB] = 3.6*K[SUB]h[/SUB] / T

where
     P[SUB]ave[/SUB]   is the short time average power in kW over the "time of measurement"
                 in seconds.
     K[SUB]h[/SUB]    is the meter scaling constant in Wh (watt-hours) per dot sequence 
                 step.
     T     is the time in seconds for one step of the dot sequence. 
           = "time of measurement" / number of dot steps.

Any comments?

.

 

[mivey]

130828-0944 EDT

I have now converged on describing the average power equation as:

P[SUB]ave[/SUB] = 3.6*K[SUB]h[/SUB] / T

where
     P[SUB]ave[/SUB]   is the short time average power in kW over the "time of measurement"
                 in seconds.
     K[SUB]h[/SUB]    is the meter scaling constant in Wh (watt-hours) per dot sequence 
                 step.
     T     is the time in seconds for one step of the dot sequence. 
           = "time of measurement" / number of dot steps.

Any comments?

.

I would prefer a more general form since we may have a meter multiplier or a non-unity indicator count (or # revolutions):

Pave = 3.6 * PKh * #revolutions(or # indication steps) / T

Pave = average power in kW over measurement interval
Kh = secondary watthour constant = meter Wh per disk revolution(or per indication step)
TF = Transformer Factor = CT Ratio x VT Ratio = meter multiplier
PKh = Primary Wh per disk revolution(or per indication step) = Kh x TF
T = time in seconds for # revolutions(or # indication steps)

also,
kWh = Pave * measurement interval in hours = Pave * T / 3600 = PKh * #revolutions(or # indication steps) / 1000

where kWh is the energy through the meter during the measurement interval (assuming energy flow in only one direction during the measurement interval).

 

[K8MHZ]

130817-0829 EDT

In Western Michigan (Consumers Power) what is the brand and model number of smart meter that is being used for residential service?

If the meter is an Itron, then:

1. Is the the scaling factor 1.0 Kh? Any idea what Kh means?

If it were Wh, then it would make sense. On DTE meters I have seen 1.0 Kh, and 10 Kh. On the normal residential meter the 1.0 Kh is present and each step of the dot sequence is 1 Wh, on some commericial meters with 10 kH each step is 10 Wh.

2. Is the display a single digital section quantized to 1 kWh, with an area below the 004 sequence number having a sequencing of square dots, triangle, and blank for fine Wh resolution?

3. What on-line graphical data is provided at the power company (Consumers) website?

4. If you have one of these meters, then what is your typical average sleep time base load power usage?

Last winter with with gas heat, water heater, and range top, one refrigerator, two freezers, and miscellaneous competers and other small loads on all the time my base load was about 825 W, in the spring about 650 W, and now with one freezer and some other items off I am in the range of 300 to 400 W. The only gas item using electricity is the furnace and it is about 200 W average.

.

Mine is an Itron I210.

So far, the promised web site has not been created by Consumers Energy so, at least for Western Michigan, we do not have access to that data.

Also, the info another poster gave about the square and blank sequencing is the same info I got from the POCO when I called them to ask about reading the meters.

 

[meternerd]

Mine is an Itron I210.

So far, the promised web site has not been created by Consumers Energy so, at least for Western Michigan, we do not have access to that data.

Also, the info another poster gave about the square and blank sequencing is the same info I got from the POCO when I called them to ask about reading the meters.

I-210 is a GE meter.

 

[gar]

130828-1938 EDT

mivey:

Thanks again.

The equation is for an ordinary consumer and I want to keep it simple. However, I will add the restriction that the equation should be used for unidirectional power flow. Indirectly I have stated this by saying that the background or base power level must be stable before, during, and after a specific load is measured.

.