PIP 3024MSE Charging Slowly?

[Sonic01]

Hi Gents,

So first question,I got my PIP online today, it has a 24v 7s40 battery using a 60A 7s BMS, AC input and output but no solar currently.

I've set it to charge at 25A from AC but my PIP is only reporting 11A charge... I've attached config pics below... does anyone have any ideas?











Any tips would be much appreciated!

 

[Korishan]

Just curious, have you verified that it's charging at 11A externally?

Altho, if the PIP sees it's charging at 11A and you have it to charge at 25A, I guess that wouldn't really make a different :huh:

 

[Sonic01]

Just curious, have you verified that it's charging at 11A externally?

Altho, if the PIP sees it's charging at 11A and you have it to charge at 25A, I guess that wouldn't really make a different :huh:

does the PIP show the charging current anywhere? i cant see it? i could only tell by looking at the BMS

also what did you mean charging externally? do you mean taking my own meter readings on the battery leads?

 

[not2bme]

Your bulk charge is set to 28.2V. It probably hit that target and switched to CV so it is lowering its amperage to keep the constant voltage. Let your pack drain to 27.5V and charge it up again. Does it read 25A?

 

[Sonic01]

Your bulk charge is set to 28.2V. It probably hit that target and switched to CV so it is lowering its amperage to keep the constant voltage. Let your pack drain to 27.5V and charge it up again. Does it read 25A?

i thought that but it was saying the same at 26.9v... i also tried raising the bulk charge and float points to like 31v or something and it made no difference

 

[Korishan]

When I mean check externally, I mean using a DMM to verify voltages (at the battery terminals and at the charger connection), and to read the amps being charged at (clamp meter if you have one)

 

[Sonic01]

When I mean check externally, I mean using a DMM to verify voltages (at the battery terminals and at the charger connection), and to read the amps being charged at (clamp meter if you have one)

no idea what DMM means but I'm guessing you mean a voltmeter no I haven't checked yet, currently I've set the primary source to battery so once its full drained I'll check with a voltmeter during the charge from low voltage and see what happens.

 

[Korishan]

DMM = Digital Multi Meter

 

[Sonic01]

DMM = Digital Multi Meter

figured well i drained it right down to 23v and increased the wiring capacity on both -/+ to 44amps and it started charging from AC at 20 Amps... still not the 25 amps it should be... but still, this is good enough for me, I only plan to charge via solar and my PV max ampage is 16A so this is fine.

 

[completelycharged]

It may be due to the way you have connected the battery pack and the resulting voltage drop to the pack.

On the screens you show one is saying 27.61V and the other 28.06V at 11A current flow which is a 450mV drop or difference between the reading points. If the two are 28.06V internal to PIP and 27.61V at the pack then this would mean you rleads between the PIP and pack have a resistance of 0.041 Ohms.

At 22A the volt drop between PIP and pack would be 0.9V. This may be creating some of the difference as to when the PIP is switching to CV at a lot lower pack voltage than expected (or reading at the pack) because the voltage internal to the PIP is higher.

Separate thought - how does the PIP screen determine the battery % as it is showing 100% when at 28.06V - indicating it would be at CV...

 

[Sonic01]

It may be due to the way you have connected the battery pack and the resulting voltage drop to the pack.

On the screens you show one is saying 27.61V and the other 28.06V at 11A current flow which is a 450mV drop or difference between the reading points. If the two are 28.06V internal to PIP and 27.61V at the pack then this would mean you rleads between the PIP and pack have a resistance of 0.041 Ohms.

At 22A the volt drop between PIP and pack would be 0.9V. This may be creating some of the difference as to when the PIP is switching to CV at a lot lower pack voltage than expected (or reading at the pack) because the voltage internal to the PIP is higher.

hm interesting, that might explain why the charge rate went up so much after i swapped the positive lead from the pack to PIPout from a 14awg 32A rated copper silicone wire to a 57amp rated PV wire. maybe thats why I'm now getting a much closer reading between the 2?

My PIP negative to BMS is currently 2x 16awg 22amprated silicone wires (so 44a combined), I'll probably move them later to something rated 120-150 amps and see if it improves more. the positive will get upgraded to match as well.

Separate thought - how does the PIP screen determine the battery % as it is showing 100% when at 28.06V - indicating it would be at CV...

No idea - a youtube video i saw from another PIP user said the PIP has no shunt and therefor no real way to calculate the %, so the figure should be completely ignored - they shouldnt have even added it to the GUI.