As touched on in post `/forum/topic/6`, there should be additional standardized point definitions for an elecMeter equip. Today we have

• elecKw: demand in kW
• elecKwh: consumption in kWh

Those are obviously the two biggies (and might not actually be that simplistic in real life). Additional points to consider:

• power factor
• voltage
• current

We need domain experts to help address these questions:

1. what are other commonly measures points which are used enough to warrant standardization?
2. we need a concise description of what each point measures and what unit (or units) should be used for the measurement

Typically, here are basics informations we want to find a power monitoring device.

Generally, phases are known as A,B,C. Phase-neutral could be written L-N (Line neutral) or P-N (Phase-Neutral) For tags, maybe we could forget the L-N or P-N. ex. voltA,... would be clear enough... Phase-Phase readings should be AB, BC, CA form. ex. voltAB...

This list could be a good place to begin. Those are only suggestions, for some points, I used two lines to submit different possible ways.

Readings

• Volt Phase-Neutral for all 3 phases (V)
  • voltA, voltB, voltC
• Volt Phase-Phase for all 3 phases (V)
  • voltAB, voltBC, voltCA
• Current for each phases (A)
  • currentA, currentB, currentC
• Average of all phases (A)
  • currentAvg
• Power factor for each phase
  • pfA, pfB, pfC
• Power factor (average of all phases)
  • powerFactor
• AC Frequency
  • frequency

Energy (accumulated)

• Accumulated Real Energy (kWh) for each phases
  • realEnergyA, realEnergyB, realEnergyC
  • kWhA, kWhB, kWhC
• Accumulated Real Energy (kWh) total of all phases
  • realEnergy
  • kWhTotal
• Accumulated Reactive Energy (kVARh) total of all phases
  • reactiveEnergy
  • kVARhTotal
• Accumulated Apparent Energy (kVAh) total of all phases
  • apparentEnergy
  • kVAhTotal

Actual demand (calculated over an interval, usually 15 minutes) This will define what is the peak

• Real power(kW)
  • demand
  • kWDemand
• Reactive power(kVAR)
  • reactivePower
  • kVARDemand
• Apparent power(kVA)
  • apparentPower
  • kVADemand

Instantaneous power (each phase/total) Units are telling a lot for thoses points, it could be a good choice to use units as names, instead of there real names...

• Real power(kW)
  • kWA, kWB, kWC, kWTotal
• Reactive power(kVAR)
  • kVARA, kVARB, kVARC, kVARTotal or kVARSum
• Apparent power (kVA)
  • kVAA, kVAB, kVAC, kVATotal or kVASum

You certainly noticed tha A,B,C is lost for those tags... it could be better to use ex. kVA_A

Peaks / Max demands

• Max Real power(kWh)
  • kWhPeak or kWhMax
• Max Reactive power(kVARh)
  • kVARhPeak
• Max Apparent power(kVAh)
  • kVAhPeak
• Timestamp of peaks
  • This could be a tag of each peaks tags ? as timestamp certainly exists ?

As reference, here are 2 links pointing well known devices

• Veris
• Wattnode

Best regards,

Christian Tremblay

Christian, thank you very much for contributing info to this topic to help flush out the electric meter model. My goal to try and review this material and work with John to make a formal proposal (hopefully in next week or two). If anybody else has domain knowledge, please share for proposal input.

I'd like to add a few more commonly points to elecMeter for next rev.

First off I'd like to suggest a breaking change. The current tags for demand and consumption are elecKw and elecKwh respectively. I've had comments that maybe we shouldn't force to be in a specific unit (allow W, kW, MW, etc) and use generic terms. But I think that is the wrong direction b/w these are the probably the two most important points in the entire Haystack model and I think agreeing to force a consistent unit for modeling is worth trade-offs for simplicity. Still if anyone disagrees, now would be good time to discuss.

Instead I want to suggest that we shorten these tags to kw and kwh and drop the elec prefix. Couple reasons:

• the elec prefix is redundant (it is a remnant of when I was using a convention of prefixing all point tags with their equipment name)
• I find myself typing these tags more than any other tags in the system by an order of magnitude and shorter is better
• It is more easily combined consistently for names like kwhPeak (either as tags or functions)

Here are some other common points which I think we can nail down:

kw  sensor           // rename elecKw
kwh sensor           // rename elecKwh
current avg sensor
current a sensor
current b sensor
current c sensor
volt avg sensor
volt a sensor      
volt b sensor      
volt c sensor      
volt ab sensor
volt bc sensor
volt ca sensor
pf avg sensor
pf a sensor
pf b sensor
pf c sensor
freq sensor

Those are just the sensor readings proposed by Christian reworked for new tagging conventions. I seem to see these quite a bit and they seem pretty straight forward compared to getting into the more complicated aspects of real/apparent power, etc.

Specific questions:

1. Is there any objections or feedback on renaming elecKw and elecKwh?
2. Any comments on new points? All the phase combo's look ok?
3. What units are commonly used for current/volt in field? Just Amps and Volts?

1. Overall I don't see a problem with tagging the elec points like this, I just want to be clear on a few things:
   • It seems like you are going the direction of just adding the unit as a tag on the electrical point. So if you wish to have points that are W, MW, GW, etc... Do you visualize using these tags as well?
   • Although this is the ElecMeter post would you envision doing this for other types of meters as well, for example; a gas meter may be tagged with btu or therm?
2. The other new points look good as a good starting point.

It seems like you are going the direction of just adding the unit as a tag on the electrical point.

Just for kw and kwh as short, normalized tags. I think it will make rate modeling more straight forward too when we want to create tags like costPerKwh or whatnot.

Also brainstorm that Nick had, instead of having lots of tags like a, b, ab for phase, let's have just one tag called phase that has the string values "A", "B", "C", "AB", "BC", or "CA". Think that is cleaner and more consistent with how we did stage tag for cooling/heating stages. Maybe also get rid of avg tag and say that is just the omission of the phase tag.

Brian,

I'd like to revive this topic as we have a client who has a use case for all these extra tags.

What is the status of this proposal? I checked the tag documentation and it appears as if none of the suggestions here have been implemented.

What is needed to move this forward?

regards, Richard

What is the status of this proposal? I checked the tag documentation and it appears as if none of the suggestions here have been implemented.

I added all the tags Nov 2011 proposal (with phase changes as suggested by Nick). So they all are all there in Elec Meter. That includes power factor, current, and volt with different phases.

What specifically other points did you want to standardize?