Steve Fractals
New Member
- Joined
- Sep 6, 2022
- Messages
- 172
Not yet had a reply from MPP but only been a day.
After lots more reading, I don't think this is an inverter issue but I still could be wrong. It appears that the charger in my inverter uses both voltage and resistance to monitor whilst charging. So this should/could mean that bulk charging also includes absorption.
I watched it today and can see that it pumps charge in at a decent rate of 9.6 amps (max set to 10a) and continues at that rate even when bulk charge set rate has been reached. It continues at this 9.6 rate until the batteries get to about 34ah's stored. It then slowly ramps down but still charging at 3.6amps current until the 36ah ish mark. Then it seems to keep slowly dropping the current until it goes below 1 amp.
At the same time the battery monitor shows various Int Resistance numbers with it showing at around 186m ohm whilst still pumping in at around 3.5-6 amps. Then when it gets to 36ah's stored on the monitor it ramps down again to under 1amp current with resistance jumping between 117m ohm and 300+m ohms and then just sits pumping between .3 and .6 amps current with the resistance fluctuating. I have also seen the Int resistance display on the monitor drop to 0 m ohms a few times which I'm guessing means open circuit and will not accept any charge which would to me at least indicate the batteries are full.
With this pattern, I'm now back to wondering if I've been sold batteries with a fake capacity rating being more like 35ah instead of the quoted 130ah. I guess I really need to break the pack and test individually with a 12v charger. Means I'll have to borrow or buy one as don't own one but hey ho.
Thought's anyone?
After lots more reading, I don't think this is an inverter issue but I still could be wrong. It appears that the charger in my inverter uses both voltage and resistance to monitor whilst charging. So this should/could mean that bulk charging also includes absorption.
I watched it today and can see that it pumps charge in at a decent rate of 9.6 amps (max set to 10a) and continues at that rate even when bulk charge set rate has been reached. It continues at this 9.6 rate until the batteries get to about 34ah's stored. It then slowly ramps down but still charging at 3.6amps current until the 36ah ish mark. Then it seems to keep slowly dropping the current until it goes below 1 amp.
At the same time the battery monitor shows various Int Resistance numbers with it showing at around 186m ohm whilst still pumping in at around 3.5-6 amps. Then when it gets to 36ah's stored on the monitor it ramps down again to under 1amp current with resistance jumping between 117m ohm and 300+m ohms and then just sits pumping between .3 and .6 amps current with the resistance fluctuating. I have also seen the Int resistance display on the monitor drop to 0 m ohms a few times which I'm guessing means open circuit and will not accept any charge which would to me at least indicate the batteries are full.
With this pattern, I'm now back to wondering if I've been sold batteries with a fake capacity rating being more like 35ah instead of the quoted 130ah. I guess I really need to break the pack and test individually with a 12v charger. Means I'll have to borrow or buy one as don't own one but hey ho.
Thought's anyone?