Current Cost Support Forum

During setup, the EnviR is first paired with the transmitter as a Type-2 pulse-count device (with the EnviR displaying the text "data" but no values), and then as a Type-1 device that shows "Energy Now" wattage on the EnviR screen. Does anyone know how the "Energy Now" wattage is calculated? I'm puzzled because when I check what is being reported by my EnviR using C2 Terminal, the wattage numbers are being updated more frequently than the pulse-count numbers whereas I expect them both to update at the same time (the "Energy Now" being determined from change in pulse-count times IPU divided by change in time).

I think I've answered my own question, and am posting it here in case it helps others.

The "Energy Now" value is calculated within the transmitter according to an internal algorithm that uses the frequency of pulses and the energy per pulse, and is transmitted as a separate channel to that of the pulse-count "data" channel. Hence, the transmitter requires 2 sensor channels on an EnviR monitor, one for "Energy Now" (watts) and one for "data" (cumulative pulse-counts).

The energy per pulse has to be specified, and the default is 0.001 kWh/pulse (expressed as 1000 pulses/kWh or "ipu"'s). This can be changed when pairing the transmitter and EnviR, but surprisingly it is set when pairing the data channel even though its value is actually used in the Energy Now channel. I set my system to 100 pulses/kWh and got an "Energy Now" reading that was ten times what it would have been with the default settings, so it works as I described it.

To see how accurate the Energy Now algorithm is, I've plotted power consumption (for gas using my GaSmart) according to the Energy Now channel and the (more accurate) Meter Reading channel. Over the period, Energy Now underestimates power usage by 25% because it seems to zero low power consumption.

Chart.png [ 11.64 KiB | Viewed 38830 times ]

Indeed, I always wondered how well the real time display worked and before the product for electricity was launched I thought they would have used the clamp to read the amps so the display could more accurately react to a changing load.

Of course, systems on sale and the USA measure volts and amps to get true AC power and sample every second to give a very near real time display rather than a sum of what happened in the past (every six minutes I think the netsmart updates the website).

Automan.