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The Vital Sequence:

How to Shut Down the Solar System Before Service

When a cell in the battery bank needs to be replaced or maintained, you don't just turn things off at random. If you do it incorrectly, you risk nasty sparks, destroyed BMS boards, or fried inverters.

In the video below, you can see my step-by-step procedure for safely removing the voltage from the system:

Step 1: The inverter is turned off/disconnected.

Step 2: The solar panels (PV) are disconnected via the breakers under the MPPT controllers.

Step 2a: Always turn off the solar panels first, then the battery bank.
When turning the system on, first turn on the battery bank, wait until the fan stops spinning, and then turn on the solar panels.

Step 3: The battery breakers are trapped.

Step 4: The balancer/BMS plugs are pulled out (as shown in the video).

Step 4a: If there is more than one multi-connector, always remove the connector without the ground/zero wire (connector 2) first, and then remove connector 1.
Installation or Reinstallation is done in reverse: connector 1 is installed first, followed by connector 2.

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