Growatt Commercial C&I Setup

aqsc

Hi All,

we are lookin to install a solar & battery system for a community centre whos service voltage is 600V 3P

we are looking to go with the growatt WIT100k inverter 480V 3P

there will be a back up loads panel that is 208v3P 

there will need to be 2 transformers to set up and step down the voltages.

my question is: for the demand response of the inverter, CT's are used on the incoming service cables to sense the demand of the building. The meter and CT's for the inverter are programed for 480V , while our service is 600v. will this cause a problem in sensing the demand of the building? 

Please view SLD

https://postimg.cc/phtNYRPt

BB.

Just to add a bit of information (my guesses)...

You are in the Ontario Canada area and have 600 VAC / 348 VAC Wye utility connection.

Your main loads are 600 VAC 3 phase, and the Growatt inverter is "behind" a 600/480 VAC buck transformer.

And the protected (backup power) loads are behind a 480/208(?) transformer.

The drawing you supplied is a bit of low resolution, so I am not sure about the rest of the system components (not that I am really able to speak to them anyway--Way out of my knowledge range).

Regarding the CT feedback to the inverter--I guess this is to limit (to "zero Watts") power to the utility lines? I.e., no back feeding energy to the utility grid?

You probably need to work with Growatt and a very knowledgeable Power Engineer to workout the details of the system.

I do have another question... Is solar popular in your area? Especially during winter, you do not get a lot of sun... Using Ontario, 44 degree array tilt facing south, the "hours of sun per day" would run around:

https://pvwatts.nrel.gov/pvwatts.php

Add significant snowfalls and accumulation of snow, again reducing winter harvest until panels are cleared.
-Bill

aqsc

My apologies for the image, try this one?

https://postimg.cc/JDrH1HBt

its popular for residential and net metering

its growing in popularity for commercial.

for flat roofs the angle is usually 10-15 degree tilt. facing south. 

BB.

That image is much more readable...

And a 10 degree tilt is a big help in harvest during the summer/overall...


However, it will be up to another person here to answer your question on the CT connection across 600/480 VAC circuits. It is way beyond my knowledge.

Good luck!
-Bill