# How do you calculate electrical active (3-phase) power with L1,L2,L3 (I) angles to L1 (U) and L1,L2,L3 (I) and L1,L2,L3-N (U) measurement?

I get from a Landis+Ggyr E650 electricity meter data via a serial IR head (62056-21 / D0) about every 20s. This meter provides a lot of data, but not the current actual active power (kW).

Some of the meter data is voltage, current and phase angles shown as followed.

CurrentL1 = 3.43 A
CurrentL2 = 3.35 A
CurrentL3 = 3.36 A
CurrentN  = 0.04 A

VoltageL1_N = 241.1 V
VoltageL2_N = 241.4 V
VoltageL3_N = 241.3 V

Angle U (L1) to U (L1) = 0*Deg
Angle U (L2) to U (L1) = 120*Deg
Angle U (L3) to U (L1) = 240*Deg
Angle I (L1) to U (L1) = 200*Deg
Angle I (L2) to U (L1) = 321*Deg
Angle I (L3) to U (L1) = 80*Deg


I know in general the formula P = U * I * cos phi * sqrt(3), but I am not sure how I can use these single phase values shown above to do that calculation.

How can I calulcate with these values above the 3-phase actual active power in kW?

PS: I also know that it is possible to do a power calculation by two kWh readings and time measurement, but it looks the meter is not updating the kWh counter very regularily and it takes a too long time difference (~2min) to get stable atual values.

• Page 63 shows it will display Active and reactive power: manualslib.com/manual/1632363/… Apr 3, 2022 at 15:55
• Unfortunatly does it not get send via the communication. I shared the received data there in a forum if you are interested in it. Apr 3, 2022 at 16:23
• For the one we used, we would get the data online with a 20min time lag due to the Power company data "loop" but we got all the values... Apr 3, 2022 at 16:25