I have an Anker 757 unit powering a freezer and it works very well except for one problem.

It is connected to the main electricity supply so charges battery etc. from the mains.

Occasionally we have electricity outages mainly due to faults or maintenance. We are in a rural area.

Sometimes the power will be off for an entire day and therefore the Anker will switch off when the battery runs flat.

The problem arises when the power comes back on, the Anker will charge the battery but will not switch the AC through to the freezer as it has a soft switch thus the freezer does not get power until it is manually switched on at the Anker.

How can I ensure that it does switch power through automatically? Possibly a modification.

Thanks in advance

2 hours ago, wigs said:

I have an Anker 757 unit powering a freezer and it works very well except for one problem.

It is connected to the main electricity supply so charges battery etc. from the mains.

Occasionally we have electricity outages mainly due to faults or maintenance. We are in a rural area.

Sometimes the power will be off for an entire day and therefore the Anker will switch off when the battery runs flat.

The problem arises when the power comes back on, the Anker will charge the battery but will not switch the AC through to the freezer as it has a soft switch thus the freezer does not get power until it is manually switched on at the Anker.

How can I ensure that it does switch power through automatically? Possibly a modification.

Thanks in advance

You’ve run into the big limitation of all Anker / Bluetti / EcoFlow-style power stations: they use soft-touch electronic power buttons, not mechanical latching switches. So after power returns, the AC output does NOT auto-restore, because the unit boots into standby/charging mode, not inverter-on mode. Fortunately, there are several safe and practical workarounds—no dangerous internal modification required.

Solution 1 — Use a “Keep AC On” Feature (if supported — but the Anker 757 does not)

Some newer power stations have a hidden “auto AC resume” or “UPS continuous mode” in settings.

Unfortunately, the Anker 757 does NOT have this function.

So we must use an external method

Solution 2 — Use a “Self-Resetting Relay” / “Auto-Boot Pulse Relay”

This is the simplest, safest, most reliable fix.How it works The Anker turns on when you press its AC button (a soft momentary switch). You can simulate that button press electronically with a small external relay that momentarily shorts the switch contacts. When mains power returns after an outage, the relay generates a brief pulse 》 the AC output turns back on automatically.

What you need: A 12V or 5V momentary pulse relay, triggered by mains returning. Access to the Anker’s power-button contacts (only low-voltage, safe side).

Pros Works 100% automatically. No need to open or modify the inverter section—only the button circuit. Very low risk.

Solution 3 — Put the freezer on a separate auto-switching bypass(autmatic transfer switch) where the left top side input is the primary switch and the right top side input is the secondary switch(NO changes to Anker) If Anker is wired to the right hand top input and the Anker is off the ATS will change left side to activate utility to power the fridge as soon as the Anker comes online the ATS will change back to primary feeding the fridge from the Anker. I would use the latter no interference with the Anker circuitry.

Thank you for your suggestions. I will certainly look into implementing Solution 3.