skepticcyclist
Member
That is not true. I had grid charging activated when I had my panels removed during a reroof of my house. I ran my house off my battery during peak time and recharged fully from the grid during non-peak time.
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Grid charging update
- Thread starter h2ofun
- Start date
gcsutton
Member
If you're grid charging to charge up to your backup reserve, this is true. However, if you're in time-based control mode and the Powerwalls decide they need to grid charge, they'll go up to 5 kW each. In the screenshot below, my setting used the backup reserve at midnight to reach a set level, charging at 3.3 kW. Just before peak I turned on grid charging again because solar was less than expected and the Powerwalls started charging at 10 kW and then backed off to 8 kW to make it to 100% by 3pm (I have two Powerwalls):
Mine start off at about 1.6 per PW and then after some time both max out at 5.4 per. Maybe with that many they leave it at 1.6 to not overload anything.
That's what I'm seeing too - I did a bit of grid charging after a few days of clouds/rain to get my reserve up, max grid pull was to get 1.6kw inbound to PW, dropping to 0 when the sun peeked out and panels produced enough to cover house + at least 1.6kw to PW.
I wonder with my 7 batteries, if I am on stormwatch, would I pull 35kw from the grid? Hope I have a good transformer.
RKCRLR
Active Member
And that's only if you aren't running anything in your house...I wonder with my 7 batteries, if I am on stormwatch, would I pull 35kw from the grid? Hope I have a good transformer.
You could do a stress test and turn everything on. But your wife might not be amused if it goes awry.
My understanding is that a 200A service should be capable of delivering 48kW and I think that you have a 400A service, so you should be good. Your original PTO should have been for at least 22.8kW based on your two SE-11400 inverters. Have you logged into the the TEG(s) to see what the site export limit is set to in the summary section? I think that the same as the import limit.I wonder with my 7 batteries, if I am on stormwatch, would I pull 35kw from the grid? Hope I have a good transformer.
I have 4 batteries on 1 GW, and 3 on another.
How and where do I log into the gateway to see limits? Is this via installer account or something easier?
This is in the customer view. You can either connect directly to each TEG's private WiFi network and log in to see it, or if you know the local IPs on your network than you can connect using those IPs which would be something similar to https://192.168.1.40
It has been a long time since I set up the local account (which is not the same as your Tesla account) and you might need the password that is on the inside of the TEG.
I have personally seen a 200A service on a 5 kVA and 10 kVA transformer. I personally have a 25 kVA labeled transformer for my 400A service that presented a load calculated 232A to PGE when I requested a 400A service upgrade.
Just because you have a serving size of X, doesn't mean anything about your transformer. However, if you start to regularly pull 50 kVA from a 10 kVA transformer the utility will soon need to replace it, and you may be out of power in the meantime.
At most, you could expect the transformer to be 80% of the service size. So a 200A service might possibly need a 38 kVA transformer to deliver 160A continuous.
EDIT Also, Site import and conductor export limits are very different things. It terrifies me that a customer can just log in and change these.
Wow, that seems crazy to me. I can understand under sizing when a transformer is serving multiple homes, but for a 1:1 situation that seems like a recipe for disaster.
I know, it seems crazy but it is the utility job to provide and maintain that equipment. They can undersize it and then both the customer and utility deal with the consequences
All those cases I mentioned were dedicated transformers, or transformers only serving multiple services on the same property.
How much analysis do you think goes into approving a PTO request? As an installer, do you have access to information that lets you know if the transformer feeding a property is sufficient to proceed since the PTO request happens after installation or is just Tesla that files after the fact?
PGE handles this 100% and we have no visibility or input. We file for PTO and they tell us whether there are limitations or a transformer upgrade is needed.
I have logged into the TEG, and I see nothing but summary info, nothing about limits.
Weird, so you get to the Summary screen and scroll to the bottom and then it doesn't look like this?
Not sure why the results would be different from account-to-account.
