Pv system running watts

[vino1982]

Hello, i just had a 39 panel system installed 11.7 kwh total. 300 watt panels, with mini inverters. something odd i have discovered is the pv system drawing current 24/7. i found this by installing a kwh monitoring sytem in my electrical panel... Having shutoff all the breakers except the main breaker, my interent modem and the pv sytem disconnect i get a constant draw of 698 watts... if i shut the pv sytem disconnect off I get a reading of 0 watts total household consumption. which is what you would expect having all the breakers off... an interesting thing I also found, with all the breakers on by switching the pv system disconnect on and off I see a 298 watts fluctuation in total household consumption... i did not consider the pv system drawing power therefore it having to contend with its own consumption before it produces... if it is in fact drawing 298 watts 24/7 thats roughly 214 kwh usage a month! ouch.

[ButchDeal]

Hello, i just had a 39 panel system installed 11.7 kwh total. 300 watt panels,

Thats 11.7kW (no H) you have 39 modules at 300w each so 39 X 300watts = 11,700 watts = 11.7kw
The H comes into play over time and would be significantly more in a day

with mini inverters.

Micro inverters or micros for short

something odd i have discovered is the pv system drawing current 24/7. i found this by installing a kwh monitoring sytem in my electrical panel... Having shutoff all the breakers except the main breaker, my interent modem and the pv sytem disconnect i get a constant draw of 698 watts... if i shut the pv sytem disconnect off I get a reading of 0 watts total household consumption. which is what you would expect having all the breakers off... an interesting thing I also found, with all the breakers on by switching the pv system disconnect on and off I see a 298 watts fluctuation in total household consumption... i did not consider the pv system drawing power therefore it having to contend with its own consumption before it produces... if it is in fact drawing 298 watts 24/7 thats roughly 214 kwh usage a month! ouch.

Most micro inverter systems have a monitoring system included. Enphase has the envoy. This will draw some power but should be in the tens of watts not houndreds of watts range.
You should be able to turn off the PV monitoring system (envoy) and leave the micro inverters connected.

Is it possible that you have something else on the circuite with your inverters like a battery charger?

there is also the calibration of your monitoring system, it is likely +/-5% or such and though more accurate than that generally leaves some room.
For example you stated that it showed 0w consumption with your modem, and monitor system plugged in.

do yo have some specifics of your monitoring system and micro model/brand?

[vino1982]

Hi ButchDeal, I have two disconnects on my solar system... 1 is in between the array and the white box on outside of house... the other is in between the white box on outside of house and electrical panel. I have been the switching the latter one in my monitoring...

im looking into battery charger and specifics

thank you

[ButchDeal]

Hi ButchDeal, I have two disconnects on my solar system... 1 is in between the array and the white box on outside of house... the other is in between the white box on outside of house and electrical panel. I have been the switching the latter one in my monitoring...

im looking into battery charger and specifics

thank you

what brand & model of inverters do you have

[vino1982]

PV Module: CS6K-300MS Canadian Solar

thats what im reading off my online monitor

[ButchDeal]

PV Module: CS6K-300MS Canadian Solar

thats what im reading off my online monitor

ok that is the PV module not the inverter.
What web site are you using for your online monitoring?

is it something like http://enlighten.enphaseenergy.com/ ??

[vino1982]

myenlighten

[ButchDeal]

myenlighten

ok so you have enphase brand micro inverters. not sure of the model though, M250, S280, IQ6, IQ6+ etc.

the M250s have a night time consumption of 65mw or 0.065 watt each
you have 39 micro inverters so that would come to 2.5watts consumption.

The envoy or gateway likely consumes ~10watts.

What is the "monitoring system" that you installed? and when you did the testing was myenlighten showing zero production?

[vino1982]

the monitoring system is called "my eyedro" When I was doing my testing it was dark out and panels covered in snow, so they were not producing. im not sure if my enlighten was showing 0 production, i am assuming it was

[bcroe]

Interesting discussion. It would be good to know just what the AC standby power of any inverter
is, something else to be measured here. Small continuous loads add up, spent a couple years
fixing these before a 2013 leap into solar. Bruce Roe

[ButchDeal]

the monitoring system is called "my eyedro" When I was doing my testing it was dark out and panels covered in snow, so they were not producing. im not sure if my enlighten was showing 0 production, i am assuming it was

ok so it looks like an eyedro which does not seem to take into account some factors as it does not seem to have a voltage sensor.
So it can't account for powerfactor or voltage differences.
it doesn't seem to be able to tell the difference in the direction of energy flow from the web site, so it couldn't tell if it was load or generation.

[vino1982]

ok, i can see that not knowing load or generation. but at night with the panels not producing should i not see any generation anyhow? in activating/deactivating the pv disconnect at night shouldnt have any effect on wattage generation since they are not generating. if that makes any sense

[ButchDeal]

ok, i can see that not knowing load or generation. but at night with the panels not producing should i not see any generation anyhow? in activating/deactivating the pv disconnect at night shouldnt have any effect on wattage generation since they are not generating. if that makes any sense

possibly,
but that said it is not clear the the eyedro has the correct voltage as it doesn't have a voltage sensor connection.
there may be other draws on the circuit with the micros as well.
Do you have a storage system? enphase AC batteries or other batteries or UPS.

[vino1982]

the eyedro does not have a voltage sensor but it does allow me to put in what the voltage is on each leg of power. in my case testing hot to ground i have 117 volts on each leg, which I input to eyedro... i do not have any storage batteries. i am not certain if there is a battery inside the white box on the house for backup purposes... i will find out

[ButchDeal]

the eyedro does not have a voltage sensor but it does allow me to put in what the voltage is on each leg of power. in my case testing hot to ground i have 117 volts on each leg, which I input to eyedro... i do not have any storage batteries. i am not certain if there is a battery inside the white box on the house for backup purposes... i will find out

I don't know what the white box is that you mention but it is unlikely a battery. could you upload a photo of it?

Yes I read the instructions on the eyedro about putting in the voltage but distribution network voltage is not constant and fluctuates quite a bit throughout the day.
Your PV system will increase the voltage when it is working as well.