Release Version of Patched Firmware 74.40e for some 48 V PF1.0 58.4 V 5 kW models
[Edit: On 30-Jul-2020 we replaced beta 74.40e here, with release 74.40e. The only change was the first letter of the version number (from B to L). This was after 5 months and 107 downloads of the LFP version and 82 downloads of the Lead aCid/Lithium Cobalt version, with zero bug reports.]
This is the first version of our patched firmware based on factory firmware version 74.40 for the Axpert MKS 5K-48 (
non 64 V), Mecer SOL-I-AX-5P (
not SOL-I-AX-5P64), and equivalents. I note that MPPSolar don't sell an equivalent PIP model at this point. There were no patched firmware versions 74.40a-d. We jumped straight to "e" so that "e" (and later) would indicate the presence of the kettle-compensation feature, as in 73.00e for PF0.8 models, and 72.20e for PF1.0 64 V models. See the
first post of this topic for these and other patched firmware versions.
This patched firmware has all the same patches as both 73.00e, 72.20e, and earlier patched firmwares, including
Dynamic Charge and Load Control,
AussieView™, and KettleKomp™. This includes fixing the infamous
premature float bugs.
It's been a while since all the patched firmware features were listed, so here is a summary:
Change Summary
LFP† and Lead Acid Patched Firmware
- The repaired voltage criterion for transitioning from absorb stage to float (main premature float bug fixed).
- For non-automatic absorb stage timing, only time when the battery voltage is near the CV setting counts as being "in absorb" (second premature float bug fixed).
- "Font" improvements, and HS -> MS for Master units.
- Firmware revision display screen contains patch revision.
- Fixed "change a setting twice", and "limited steps" bugs in factory firmware.
- Improved the accuracy of all charge and discharge current readings.
- AussieView™ improved display of data.
- Dynamic Charge Control (DCC): vary charge current by commands without wearing eeprom and without delays.
- Dynamic Load Control (DLC): switch inverter-proper on and off by commands to save idle power drain.
- KettleKomp™ (load/charge compensation for important battery voltage measurements).
LFP patched firmware only
- The bulk/absorb to float transition occurs with a different current threshold: (sum of maximum charge current settings) divided by 12, minimum 3 A.
- Low battery cutoff voltage range changed from 40-48 V to 44-52 V.
- Back to utility voltage range changed from 44-51 V to 46-53 V.
- Float to bulk charge stage transition occurs at 1.2 V under the float setting.
- The battery low warning occurs at the cutoff voltage plus half a volt, and returns at cutoff plus one volt.
More details on the features can be found
here and
here, and in the manuals linked near the top of this post.
Paralleling PF0.8 and PF1.0 58.4 V machines
Unfortunately, there is no proper way to do this, unless your PF1.0 machine(s) all have factory firmware version 74.10; then you can parallel with factory firmware 72.70 in the PF0.8 machines. Failing this (there would only be a handful of machines with firmware version 74.10, and I don't know of any firmware update files for that version), then the following is a RISKY possibility. You could flash 74.40e into all machines, PF1.0 and PF0.8. Note that this will make the PF0.8 machines think that they are PF1.0 machines, so the fans won't work as hard, and the firmware will let your power loads up to 5 kW without triggering an overload. This is likely very bad for your PF0.8 machines. However, in a paralleled situation, it may be possible to guarantee that the total load when shared amongst all paralleled machines will very rarely if ever exceed 4.0 kW, so the PF0.8 machines should be safe. If you do this, you do so AT YOUR OWN RISK!
This patched firmware is intended for: some genuine 48 V PF1.0 58.4 V (i.e. NON 64 V) 5 kW models.
Do not attempt to use with
clones, workalikes, or 64 V models. Check setting 26 before you flash: if you can choose values higher than 58.4 V, then you have a 64 V model, and this firmware won't work. This patched firmware is not for any model with a 450 V MPPT, or PWM Solar Charge Controller; only for models with a Solar Charge Controller limited to 145 V Voc at the PV input. It is not for any model with a removable display, or for 24 V or 12 V models, or for any apparent power rating less than 5 kVA.
The 'L' initial letter indicates a re
Lease version (tested by many users with no problems reported). It also stands for either "
Lithium" or "
Lead".
The 'F' second letter indicates the L
FP flavour, or 'C' for Lead A
Cid /
Cobalt blends.
The '1' third character indicates that this is main (DSP) firmware, not SCC / display / Bluetooth firmware.
For lithium ferrous phosphate (LFP)† (16S or 15S) or lithium manganese oxide (LMO) (14S).
For lead acid (24S), lithium cobalt-blends (LCO, NMC, NCM, NCA) (14S), and lithium titanate (LTO) (21S or 20S)
For reflashing instructions see the
72.70b reflashing instructions, but ignore the zip files there.
It should go without saying that you use this at your own risk. Please report any problems to this thread.
† "Lithium ferrous phosphate" and "LFP" are the preferred name and abbreviation for what is sometimes called lithium iron phosphate or LiFePO₄.
[ Edit: added DCC and DLC features; added Axpert and Mecer model numbers. ]
[ Edit: removed a chunk out of "Testing to date", which we suspect would happen with factory firmware anyway, as we didn't touch the battery calibration code. ]
[ Edit: replaced original zip files with versions that contain a minor update to the KettleKomp™ manual. This mentions more directly how the maximum charge current of paralleled inverters affects the strength of battery voltage compensation. Thanks, Weber! ]
[ Edit: replaced zip files with ones that have slightly corrected .txt files. The error was quite minor, and has no effect on the final dsp.hex file. ]
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
