Export Power via Solar Inverter DIY

[21st Century Pony]

So does that mean any Joe can just walk by your house and turn your power off?

...and the gas meter as well.

They can even steal our mail from the mailbox.

Yet we trust our fellow Virginians and we have for the 19 years we've lived here. Even our grill had never been stolen. Ditto for our patio hanger plants. Even our unsecured rake and the two unsecured snow shovels... not to mention the two unsecured kayaks.

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[mkhuffman]

...and the gas meter as well.

They can even steal our mail from the mailbox.

Yet we trust our fellow Virginians and we have for the 19 years we've lived here. Even our grill had never been stolen. Ditto for our patio hanger plants. Even our unsecured rake and the two unsecured snow shovels... not to mention the two unsecured kayaks.

I agree with all of that. My grill has never been stolen either, and I don't worry it will be. But I am not a fan of providing a easy off switch on the exterior of my house. I don't like to make it easy for criminals, which is the same reason I have a security system. You would laugh at me if you knew where Iived.

 

[21st Century Pony]

I agree with all of that. My grill has never been stolen either, and I don't worry it will be. But I am not a fan of providing a easy off switch on the exterior of my house. I don't like to make it easy for criminals, which is the same reason I have a security system. You would laugh at me if you knew where Iived.

The solar PV system is a supplement to the normal electric feed into the house.

The outside cutoff switch my jurisdiction demands for solar grid-connected net metering systems is to keep linemen safe when they are trying to bring a downed section of the grid back up.

Switching the cutoff switch OFF merely cuts PV power input. It might (!!) be a teen prank, maybe, but it would not keep grid power from my house.

 

[mkhuffman]

The solar PV system is a supplement to the normal electric feed into the house.

The outside cutoff switch my jurisdiction demands for solar grid-connected net metering systems is to keep linemen safe when they are trying to bring a downed section of the grid back up.

Switching the cutoff switch OFF merely cuts PV power input. It might (!!) be a teen prank, maybe, but it would not keep grid power from my house.

Oh. Now I understand. I would be OK with that.

 

[RodMachE]

I'm going to put this up front. This is a bit extreme and slightly dangerous. Hopefully I covered for most circumstances. I'm open for suggestions, but not UN-constructive criticism.

This is really just a photo session showing what I used to export power from the Heater connection of the mach E. I went through an iteration of using the AC power connection and a DC/DC power supply, but the power supply wasn't up to the task. I did some research and it seemed like the most cost effective way to convert ~380vDC to 240vAC was a solar inverter.

The solar inverter is a Growatt SPF 5000 ES. It puts out 240vAC. No split phase 120v like you need for my panel. We'll get to that in a second. The growatt can handle a max PV input of 450vDC @ 18A. It can also charge a 48vDC battery system. I can't find any PV inverter that I can afford that can handle 380vDC on the battery side. That's why I went for the PV input instead. This is one of the few inverters that can run off PV alone without any battery supplement.

On the AC Side it goes to a L14-30 twist lock into my generator inlet. From the generator inlet, it goes to a Victron 30 amp auto transformer. This turns the 240vAC into split phase 240/120vAC while balancing each 120v leg. From that point it goes into a interlocked breaker to feed the entire panel. I've used this autotransformer for both my other battery system (Ecoflow Delta Pro) and my Inverter Generator and it performs like a champ.

I sourced the vehicle connector and pins from Mouser, which was a big pain in the a$$. Ford doesn't have a part number for any of the connectors, so it was a lot of guesswork. I crimped the pins to the double insulated solar wire, and attached MC4 solar connectors. I figure those are built for some high voltage DC, so they should be up to the task.

I decided to hook to the heater power instead of the AC power because of ease of access. I only have to pull one panel to get to the heater connector vs pulling the whole frunk. Those circuits are protected in the HVBJB by a 50A fuse if i remember correctly. So i made sure I fused my solar connectors at 20A. The inverter should never draw more than 13A on the HV side, so i was able to keep the wire gauge smaller. I don't have a lot of data yet on usage/battery drain. That will be a future thing. I can run the AC unit for the house with no issue. The surge wattage on this inverter is great.

The basic hook up is: Car off, disconnect heater connector. Connect my cable. Turn car on and disable auto-off and turn off accessories. Hook up cable to generator inlet. Flip interlock breaker. On to the pictures.

Cool!

 

[Mach-Lee]

So does that mean any Joe can just walk by your house and turn your power off?

Yes, with changes to the 2023 NEC all new services will have a clearly labeled outside disconnect that anybody can walk up to and shut off. Not the best idea IMO, they didn't think through all the consequences. Firefighters have been trained to pull the meter for decades, not sure why that's no longer acceptable.

 

[Alutacon]

Next time I lose power can I bring my house to your car?

 

[bbulkow]

not missing the point at all.... since our MMEs do not have a grid-forming high output split-phase inverter on board (like the f-150), the most practical solution in my view is to have a small (1500 watt) 12vDC->120vAC inverter exporting from the MME to 'whatever' load you want. Which could be:

1. direct 120vAC loads up to 1500watts

Hi!

Getting this thread back to using a MME as a power source. I also agree that basically staying within a 1500W envelope using a 12vDC 110vAC inverter solves most of the problems I have.

One question: you state "standard 12v connection points". Which exact 12V connection points do you recommend for this use?

I would tend to go right at the battery terminals, but I remember a thread that had a better answer.

Thanks!!!

 

[dtbaker61]

Hi!

Getting this thread back to using a MME as a power source. I also agree that basically staying within a 1500W envelope using a 12vDC 110vAC inverter solves most of the problems I have.

One question: you state "standard 12v connection points". Which exact 12V connection points do you recommend for this use?

I would tend to go right at the battery terminals, but I remember a thread that had a better answer.

Thanks!!!

'advanced search' is your friend.....

https://www.macheforum.com/site/thr...120vac-power-from-lvb-connection-points.7317/

 

[Kaskaskia 309]

Why is opening the main breaker not good enough?

Because accidents happen and workers lives are at risk.
Your power is out, and crews are hands on trying to restore it. If voltage comes from your panel to the transformer on the pole, it is boosted to high voltage, thousands of volts. Someones dad might not make it home. Installing a transfer switch is the proper way its done, If you care about people.

 

[mkhuffman]

Because accidents happen and workers lives are at risk.
Your power is out, and crews are hands on trying to restore it. If voltage comes from your panel to the transformer on the pole, it is boosted to high voltage, thousands of volts. Someones dad might not make it home. Installing a transfer switch is the proper way its done, If you care about people.

Well, I definitely don't care about people.

 

[dtbaker61]

Because it’s not idiot-proof. A transfer switch or breaker interlock makes it physically impossible to backfeed the grid no matter who does (or forgets to do) anything.

if you are afraid idiots might use your generator to backfeed to the grid and try to re-energize nearby transformers, you can install a manual interlock on the dedicated circuit you will use for backfeed for about $60, or less depending what brand electrical panel/breakers you have.

https://www.amazon.com/Generator-In...-Murray/dp/B08Y78NVTH/ref=asc_df_B08Y78NVTH/?

but, this approach obviously means you need an additional dedicated 'generator-only' circuit. This is definitely safer, and relatively idiot-proof for anyone that might forget to open the MAIN disconnect before firing up the generator.

 

[i8iridium]

I wanted to come back with a small update. I bought a new solar inverter. It’s a EG4 6000xp. A little more powerful than the previous inverter. Also I mounted it. Not much has changed with the rest of the system. I tied it in with SolarAssistant running on a raspberry pi so I could measure output.

This was from yesterday when i was putting it to work charging some EcoFlow Delta Batteries. After the big load, that was just normal house load.

That was only pulling about 12 amps on the DC side from the car. So far it's a good backup system.

 

[dtbaker61]

I wanted to come back with a small update. I bought a new solar inverter. It’s a EG4 6000xp. A little more powerful than the previous inverter. Also I mounted it. Not much has changed with the rest of the system. I tied it in with SolarAssistant running on a raspberry pi so I could measure output.

This was from yesterday when i was putting it to work charging some EcoFlow Delta Batteries. After the big load, that was just normal house load.

That was only pulling about 12 amps on the DC side from the car. So far it's a good backup system.

can you revisit exactly where you are connecting to MME HV, I'm thinking about adding a 'permanent' connector available for HV output ...

Did you end up tapping DCin lines and adding a connector, or disconnecting heater supply and swapping in the PVin when you want to use it ?

my setup with 12vDC export works fine, but limited to 1500-2000 watts... can't run big loads, well-pumps, etc.

 

[i8iridium]

can you revisit exactly where you are connecting to MME HV, I'm thinking about adding a 'permanent' connector available for HV output ...

Did you end up tapping DCin lines and adding a connector, or disconnecting heater supply and swapping in the PVin when you want to use it ?

my setup with 12vDC export works fine, but limited to 1500-2000 watts... can't run big loads, well-pumps, etc.

currently, I just disconnect the heater and swap in the inverter connection. I would like to find something a little easier, but it needs to be easy to remove if I need to take the car in for warranty work. And by easy, if I’m on the side of the road because of the dreaded HVBJB failure and need to be towed directly to a ford dealer, I want to pull it out and throw it in my backpack. Lol

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