Using 30A AC Charging Cable For Split-Phase on AC300, Correct Phase?

I have two AC300’s with 3 B300’s each, working in split phase mode with a Fusion box. It all seems to work just fine. I just purchased the 30a Split Phase Charging Cable, and before I connect it I wanted to be sure I did this correctly. I seem to remember a comment stating make sure you connect the phases correctly, but how would you do this?

With this cable there are two AC300 connections and neither are marked differently, by phase or by master/slave. Does this matter, or connect it to either AC300 and you’re good to go? I intend to use a gas Generac generator for this only when needed to charge both simultaneously.

Didn’t want to blow up my Bluetti’s! Thanks

I built my own cable in June 2022 before Bluetti offered it, so I have experience.

The two female aviation type connectors and cables have different line (X and Y) wires, but share the neutral (N) and ground (G) wires, so one is X and the other is Y. I don’t know if Bluetti’s cable manufacturer labeled the female connectors . If not, just wrap masking tape around the cables, use a ohmmeter to trace from the NEMA L14-30P contacts and mark them as I did. The instalation order is not important so chose one AC300 as “X” and the other as “Y”. I chosed the Master AC300 as “X” and the Slave unit as “Y”.

The NEMA L14-30P Twist-Lock connector on the other end has four contacts, and the plug must have the X,Y,N, and G markings on it (the G contact has the curved L shape connector).

So you, or a electrician, must wire the L14-30R box (with female contacts) and the two live lines (X and Y) must be on different phases of the 240 VAC circuit with a 40A two pole circuit breaker to protect and allow to disconnect the two AC300 from your home for maintenance. It is safer and easier than twisting and pulling the L14-30P connector out .

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