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Panel Replacement / Transfer Switch questions

sealingandbolting

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Max output is 23kW, but it is 0kW when the grid is down. After a few days hte truck battery is dead, and I am out of water...
Maybe there is something getting lost, but why would your solar panels stop working when the grid goes down??? The sun doesnt stop shining?
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Inverters are designed to only come on when they see a sine wave from an AC (Alternating Current) source, and then the inverter has to match that sine wave when converting DC (Direct Current) to AC. The primary reason is so the solar system does not remain on during a power outage, back feeding to grid and transformers, which can electrocute the lineman working on the line. If the sine waves do not match between electrical sources, things blow up and catch on fire. Sine waves are very tricky. Most generators DO NOT put out a clean enough sine wave to be compatible with inverters, so unless you have special equipment that will generate a very clean sine wave, it is usually best to bypass the solar system with the transfer switch when the generator, truck or batteries come on line. The exception is if the solar system is being used just to charge the batteries so you have DC to DC, or if the AC source is a stand along generator or other other completely independent power source. Anytime a system is converting DC to AC with an existing AC source online, the sine waves have to match and be compatible between the two sources.

For years I have tried to find a safe and reliable way to put my 14.5 KWH solar system back on line after a power outage, but so far I have not been successful. I am sure at some point this will get solved economically by someone.
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wiffleballpractice

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Inverters are designed to only come on when they see a sine wave from an AC (Alternating Current) source, and then the inverter has to match that sine wave when converting DC (Direct Current) to AC. The primary reason is so the solar system does not remain on during a power outage, back feeding to grid and transformers, which can electrocute the lineman working on the line. If the sine waves do not match between electrical sources, things blow up and catch on fire. Sine waves are very tricky. Most generators DO NOT put out a clean enough sine wave to be compatible with inverters, so unless you have special equipment that will generate a very clean sine wave, it is usually best to bypass the solar system with the transfer switch when the generator, truck or batteries come on line. The exception is if the solar system is being used just to charge the batteries so you have DC to DC, or if the AC source is a stand along generator or other other completely independent power source. Anytime a system is converting DC to AC with an existing AC source online, the sine waves have to match and be compatible between the two sources.

For years I have tried to find a safe and reliable way to put my 14.5 KWH solar system back on line after a power outage, but so far I have not been successful. I am sure at some point this will get solved economically by someone.

There are plenty of folks out there with off-grid solar systems, but you would basically need 2 sets of inverters to swap between to have both off grid and grid-tie, realistically. Off grid systems also require a sizeable battery in order to properly function, which isn't required for grid-tie.

Also, you probably mean a 14.5 KW solar system, not KWH.
 

sealingandbolting

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There are plenty of folks out there with off-grid solar systems, but you would basically need 2 sets of inverters to swap between to have both off grid and grid-tie, realistically. Off grid systems also require a sizeable battery in order to properly function, which isn't required for grid-tie.

Also, you probably mean a 14.5 KW solar system, not KWH.
True. I just got in the habit of using KWH. Mussel memory...
 

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PungoteagueDave

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There are plenty of folks out there with off-grid solar systems, but you would basically need 2 sets of inverters to swap between to have both off grid and grid-tie, realistically. Off grid systems also require a sizeable battery in order to properly function, which isn't required for grid-tie.

Also, you probably mean a 14.5 KW solar system, not KWH.
Ford/SunRun supplies a battery with its bi-directional home integration system for this very reason. It also has a wall-mounted inverter and an intelligent switching system to go along with the wall charger that comes with the truck, an integrated system. It actually goes one step further and is pre-provisioned for inputs from solar panels. A battery is required to operate the land-side of the system when the grid goes down and during the automated switchover in either direction. This seamlessness was why we decided to bite the bullet and go with the Ford/SunRun system - we need it to operate when away.
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