all, wondering if you can provide some insight. I have the above mentioned battery with a horrible Mecer IVMS 1200MPPT Inverter that "supports" lithium batteries. I set the cut off to 10.8v as recommend by the manual on the box, sadly this morning I had to jump the battery to wake it up as the inverter didn't do its job.

As much as I hate this inverter, it does the job. However I've been recommended not to set the charging to 25amps as it will "blow/pop" the inverter. I notice the float is set to 13.6 but the OSD on the inverter shows 13.3. 

Should I set the battery cut off to 11.8 or so? Additionally at 10 amps, it takes more approx 16 hours to charge (according to my calculator). 

 

Should I just bite the bullet and get rid of this noisy piece of garbage from Mecer? Any advice regarding voltages would be great. 

19 hours ago, Dal2000 said:

I notice the float is set to 13.6 but the OSD on the inverter shows 13.3.

Can you elaborate, please? I'm not following.

19 hours ago, Dal2000 said:

However I've been recommended not to set the charging to 25amps as it will "blow/pop" the inverter.

19 hours ago, Dal2000 said:

Additionally at 10 amps, it takes more approx 16 hours to charge (according to my calculator). 

If there is a 25 A setting on the inverter, without knowing anything about it, I would think it should be able to handle it, and will reduce your charge time considerably. If it pops at that rated output, then it seems that it is worth replacing. [ Edit: However, see next post!! ]

19 hours ago, Dal2000 said:

I set the cut off to 10.8v as recommend by the manual on the box

That  recommendation sounds like a low value for a lead acid battery. Even lead acid should rarely be discharged below 12.0 V. If you are in area with regular load shedding, or you have an LFP battery, the low cut-off voltage should be 12.0 V, or as high as you can set it. There will be next to no run-time below that voltage anyway, assuming it is the Lithium Ferrous Phosphate chemistry (LFP).

Edited February 12, 20242 yr by Coulomb

2 hours ago, Coulomb said:

Can you elaborate, please? I'm not following.

If there is a 25 A setting on the inverter, without knowing anything about it, I would think it should be able to handle it, and will reduce your charge time considerably. If it pops at that rated output, then it seems that it is worth replacing.

 

It has become a common suggestion by sellers that the 12V version only to charge at 10A as it seems the AC charger does fail if used at the higher setting. The same applies on the 720W trolley model.

14 hours ago, Scorp007 said:

It has become a common suggestion by sellers that the 12V version only to charge at 10A as it seems the AC charger does fail if used at the higher setting.

Huh. If it's actually true, then it's false advertising, and/or a really poor design. Perhaps the hardware is capable of 25 A continuous charging, but only if the ventilation is adequate, and Mecer shoehorned it into a trolley that doesn't provide that.

Thanks for the correction, anyway.

10 minutes ago, Coulomb said:

Huh. If it's actually true, then it's false advertising, and/or a really poor design. Perhaps the hardware is capable of 25 A continuous charging, but only if the ventilation is adequate, and Mecer shoehorned it into a trolley that doesn't provide that.

Thanks for the correction, anyway.

Partly market forces and sellers. Instead of fitting a lead acid for which the inverter was designed an upgrade option is taken to a lithium battery that is power hungry during charging that seems to overload when the 20A instead of 10A charging selection is made. 

Normally the lead acid will only charge for a short period at up to 20A then the current drops so the charger seems OK. 

Trolley is also a vague description as again there are a number off different specs under the trolley configuration. Some the inverter is contained inside the box and others it is loose on top of the box. 

I set the float charge to 13.6 as recommended. When the inverter is actually "floating" the OSD on the inverter shows 13.3. The multimeter on the battery shows lower, 13.2.

I see an explanation is provided for the charging issue. Guess it's replace or keep at this point.

 

This is on special at the moment: https://www.firstshop.co.za/products/rct-axpert-vm2-premium-1200w-pure-sine-wave-inverter-with-2000w-mppt-charger-rct-axvm2-prem-1-2k-12v-169974

Any recommendations?

9 hours ago, Dal2000 said:

I set the float charge to 13.6 as recommended. When the inverter is actually "floating" the OSD on the inverter shows 13.3. The multimeter on the battery shows lower, 13.2.

I see an explanation is provided for the charging issue. Guess it's replace or keep at this point.

 

This is on special at the moment: https://www.firstshop.co.za/products/rct-axpert-vm2-premium-1200w-pure-sine-wave-inverter-with-2000w-mppt-charger-rct-axvm2-prem-1-2k-12v-169974

Any recommendations?

There are many other options too. Like a 3kW at about the same price. Yes it does need 24V but just a less over worked inverter and thus ready for the now and again high load. I firmly belief things can just get worse going forward. Having an inverter that can at least warm food has been a priority for our family. 

One cannot braai every day when LS. 

Edited February 12, 20242 yr by Scorp007