Author Topic: low temperature charging cutoff  (Read 550 times)

GaryReysa

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low temperature charging cutoff
« on: November 13, 2021, 04:28:17 PM »
Hi,
Is there any way to setup the Kid so that it will cut off charging at 32F?

This is to protect Li batteries.

Thanks Gary

ClassicCrazy

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Re: low temperature charging cutoff
« Reply #1 on: November 13, 2021, 10:33:45 PM »
Hi,
Is there any way to setup the Kid so that it will cut off charging at 32F?

This is to protect Li batteries.

Thanks Gary

No afraid not .
Classic can not do that either, though it would be more possible for a classic to do that with a firmware update.
They have said the Kid will get no more development so likely not in the future for that.
There are lots of inexpensive thermostats available that could be used  to control a relay to cut off charging and that would be one option .

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , Jakiper 48v LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batteries

boB

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Re: low temperature charging cutoff
« Reply #2 on: November 13, 2021, 11:23:24 PM »

High temperature cutoff but not low temperature yet.

It's coming !

K7IQ 🌛  He/She/It

ClassicCrazy

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Re: low temperature charging cutoff
« Reply #3 on: November 13, 2021, 11:40:22 PM »

High temperature cutoff but not low temperature yet.

It's coming !

For the Kid ?
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , Jakiper 48v LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batteries

Steve_S

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Re: low temperature charging cutoff
« Reply #4 on: November 14, 2021, 07:31:20 AM »
The BMS with your battery pack should cutoff at 0C/32F IF this is LFP (LiFePO4) and only allow a reduced charge (<= 0.25C) to 10C/50F.  Other Lithium chemistries vary on temp & charge rates at temps.

The Kid will not like having the battery drop off due to a Lo Temp Disconnect and that is when the fun starts...

Was tossing around the idea of using the KIDS 24V output to drive a small warmer (silicone warming pad) with a thermostat as a pack warmer.  I DIY my packs so it's would be easy to slip one under the cells.  But I am still tossed up as to running one off the Battery Pack Terminals or off the Kid...   pros/cons to ponder.

GaryReysa

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Re: low temperature charging cutoff
« Reply #5 on: November 14, 2021, 09:51:55 AM »
Hi,
Thanks for all the quick replies!

My BMS does not have a low temp cutout.

I will put a temperature controlled switch in the one of the leads coming down from the PV panels - less than 10 amps in my case.  Seems pretty straightforward and cheap?
Maybe a manually or temperature controlled heating pad for the battery.


Thanks - Gary


ClassicCrazy

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Re: low temperature charging cutoff
« Reply #6 on: November 14, 2021, 11:28:44 AM »
Hi,
Thanks for all the quick replies!

My BMS does not have a low temp cutout.

I will put a temperature controlled switch in the one of the leads coming down from the PV panels - less than 10 amps in my case.  Seems pretty straightforward and cheap?
Maybe a manually or temperature controlled heating pad for the battery.


Thanks - Gary

Make sure your switch is rated for DC . The arc on DC  is much different than AC . Running the switch to DC rated solid state relay is good option.

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , Jakiper 48v LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batteries

GaryReysa

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Re: low temperature charging cutoff
« Reply #7 on: November 15, 2021, 11:13:27 PM »
Thanks - it says its rated for 20 amps DC, so should be OK.

Gary