Solar output confusion

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Re: Solar output confusion

Postby Gordon-Loomberah » Thu Aug 02, 2018 2:11 pm

engineern6719 wrote:...Zeversolar inverter.


Model?
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Re: Solar output confusion

Postby engineern6719 » Thu Aug 02, 2018 3:20 pm

Zeverlution 5000
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Re: Solar output confusion

Postby Gordon-Loomberah » Thu Aug 02, 2018 7:12 pm

Is the red LED lit at any time?
>>Red LED:
The red LED is lit when the inverter has stopped feeding power into the grid due to a
fault. The corresponding error code will be shown on the display

What PV voltage is the inverter showing at say 9 or 10am on a sunny day?

What output current are you seeing in the middle of the day?

Is the inverter subject to DRED control? see p37 of the user manual

Do you have wifi monitoring set up?
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Re: Solar output confusion

Postby engineern6719 » Fri Aug 03, 2018 12:20 pm

(1) Red LED hasn’t been on at any time.
(2) Volts @ 9.15 this morning : phone app 350/340,Inverter display 300/294
(3) Current @ 1200 this morning : phone app 7.0/7.3 ,Inverter display 7.0/7.3
(4) output @ 1200 this morning : phone app and inverter 13.2kwh
DRED from what I understand is a external control of inverter output to allow the supplier to vary output.
How can I tell if this is fitted?
As you can see I have wifi monitoring setup.
Last edited by Gordon-Loomberah on Fri Aug 03, 2018 2:00 pm, edited 1 time in total.
Reason: removed unnecessary quoting
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Re: Solar output confusion

Postby Gordon-Loomberah » Fri Aug 03, 2018 2:09 pm

Can you post a graph of the system's output from the data logging and post it here? That should show whether or not the output is being cut back by DRED commands, but I doubt it is in use, otherwise you would have been told (I hope!).

There seems to be a rather large discrepancy between the string voltages reported by the phone app and the inverter.

If you had monitoring of all loads + system output, you'd be able to tell exactly what is going on, and avoid all the guessing. You'd also be able to pick up any problems immediately.
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Re: Solar output confusion

Postby engineern6719 » Sat Aug 04, 2018 7:32 am

I have 2 power monitors that are being used to check power consumption.once that is done the figures taken can be totalled for daily usage.The only thing I can’t check is the air conditioner.
I shall try and get a screen shot of the system out put.
Could somebody explain to me how the meter calculates the readings.If you are getting,for example, solar production of 23kwh/day and daily usage is 10kwh/day shouldn’t you be exporting to the grid or is it a bit more complicated than that?
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Re: Solar output confusion

Postby Gordon-Loomberah » Sat Aug 04, 2018 9:37 am

Are the power monitors the plug-in type? They can give you a good idea of individual appliances for the period being measured, but are not so useful when measuring whole-of-house energy usage and usage patterns. How are you measuring lighting energy use?

Household energy monitors monitor all loads by use of current transducers on the main active cable, plus another CT on the inverter output if measuring solar generation as well. Correct placement (very important!) of the CTs allows you to to graph imports, exports, PV system output and household usage. If you keep an eye on the monitor, it also makes obvious any problems with the PV system.

You should generally be exporting power to the grid whenever solar generation is higher than household loads.
Obviously you wont be exporting at night, but during the day export or import is determined by the rate of generation and power usage, and varies throughout the day as loads change and PV output varies with time of day, clouds, shadows on the array etc. So a simple 24hour 'solar output - energy use' calculation wont give you the amount of exported of imported energy for a day.
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Re: Solar output confusion

Postby engineern6719 » Sat Aug 04, 2018 1:41 pm

To fit the current transformers I imagine you would need a qualified electrician.Wouldnt it be easier to switch off the solar completely and monitor daily usage on the import meter.I know it wouldn’t give you the full picture but would give you daily usage plus usage during normal solar operating times.
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Re: Solar output confusion

Postby Gordon-Loomberah » Sat Aug 04, 2018 2:12 pm

Yes, you can see what total energy usage (= imports) is by turning off the solar. However, as you say, you wont get the full picture that a proper monitoring system will give you.
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Re: Solar output confusion

Postby engineern6719 » Sat Aug 04, 2018 5:48 pm

Gordon-Loomberah wrote:Yes, you can see what total energy usage (= imports) is by turning off the solar. However, as you say, you wont get the full picture that a proper monitoring system will give you.

What’s involved in fitting the monitoring system and the cost?
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