1/3/2017 8:34 AM | |
Posts: 16 Rating: (1) |
I combine voltage and amps mesurement to kw, next I use the totalizer block but the reading is not correct. I've added an attachment |
1/3/2017 9:01 AM | |
Joined: 3/5/2014 Last visit: 8/5/2022 Posts: 5521 Rating: (1051) |
hi, with what are you reading the values in? For applications like this, there are technology modules that can handle this for you. Have a look to the ET200s or ET200SP Energy meters. SIMATIC ET 200SP analog input module AI Energy Meter ST here you can see, what values the Energy meter provides
If you want to calculate it of your own, you need a fix timed interval where the calculation happens, like an interrupt OB with 100ms. Then you need to devide the power with the time, e.g. 100W / 100ms = 1 W/ms =0,0027777W/h. To totalize it, you have to add this value up everytime when the calculation is executed. But I think this is not really accurate. If you need an accurate value, I would rather use an energy meter. hope this helps, regards, |
Last edited by: mopS04 at: 1/3/2017 9:05:07 AMFCK WAR! |
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1/4/2017 4:06 PM | |
Joined: 4/19/2008 Last visit: 6/6/2024 Posts: 1525 Rating: (159) |
Hello, Small Information about the KW calculation. AC single phase amps to kilowatts calculationThe powerPin kilowatts (kW) is equal to thepower factorPFtimes the phase currentIin amps (A), times the RMS voltageVin volts (V) divided by 1000: P(kW)=PF×I(A)×V(V)/ 1000 AC three phase amps to kilowatts calculationCalculation with line to line voltageThe powerPin kilowatts (kW) is equal to square root of 3 times thepower factorPFtimes the phase currentIin amps (A), times the line to line RMS voltageVL-Lin volts (V) divided by 1000: P(kW)=√3×PF×I(A)×VL-L(V)/ 1000 Calculation with line to neutral voltageThe powerPin kilowatts (kW) is equal to 3 times thepower factorPFtimes the phase currentIin amps (A), times the line to neutral RMS voltageVL-Nin volts (V) divided by 1000: P(kW)= 3 ×PF×I(A)×VL-N(V)/ 1000 If with above calculation you get the kW.... |
Ammy |
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