Battery charge current limited to 5A
Posted: Mon Feb 02, 2026 10:48 am
I have an H1 G2 5kW inverter coupled with an ECS2900 energy cube and recently added an additional slave battery to the existing 2 slaves in place. I have two charge periods set for the winter months: 1 to charge up during the 2am-5am Octopus economy slot and another between 3pm-4pm to cover off the expensive tea-time tariff.
Everything worked fine for about 4 days and then I noticed that I was drawing from the grid at 7am, which shouldn't happen. The inverter is charging the batteries but is limiting the current to 5A - the max charge setting in the inverter is 40A - so the battery is only partially charged when the charge period ends. For the few days that everything was fine, I didn't check the charge current specifically, but the charge load was 5kW (compared to the 1kW I see now) so more than 20A.
I've seen comments that charge current is reduced when it's cold - less than 5c I think - and it's certainly warmer than that in the attic. The FoxCloud app says the battery is 11.9c and Home Assistant shows a battery temp of 23c (I think this is maybe the cell temp?).
I've tried removing the new battery pack but it made no difference so I put it back on. The new pack is an EQ2900 which Fox list as compatible with the EC2900s I already had. There's no big sticker saying V2 Type A like on the older packs but the supplier has assured me that it' compatible and I've seen references to the EQ series being type A only.
Anyway I've written too much already. No errors, red lights or other indication that anything is wrong apart from the charge current not exceeding 5A for nearly a week now. Am I missing something simple or do I need to call my installer?
Everything worked fine for about 4 days and then I noticed that I was drawing from the grid at 7am, which shouldn't happen. The inverter is charging the batteries but is limiting the current to 5A - the max charge setting in the inverter is 40A - so the battery is only partially charged when the charge period ends. For the few days that everything was fine, I didn't check the charge current specifically, but the charge load was 5kW (compared to the 1kW I see now) so more than 20A.
I've seen comments that charge current is reduced when it's cold - less than 5c I think - and it's certainly warmer than that in the attic. The FoxCloud app says the battery is 11.9c and Home Assistant shows a battery temp of 23c (I think this is maybe the cell temp?).
I've tried removing the new battery pack but it made no difference so I put it back on. The new pack is an EQ2900 which Fox list as compatible with the EC2900s I already had. There's no big sticker saying V2 Type A like on the older packs but the supplier has assured me that it' compatible and I've seen references to the EQ series being type A only.
Anyway I've written too much already. No errors, red lights or other indication that anything is wrong apart from the charge current not exceeding 5A for nearly a week now. Am I missing something simple or do I need to call my installer?