Author Topic: Modbus registers list  (Read 239 times)


  • Newby
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Modbus registers list
« on: October 26, 2021, 11:31:21 AM »
I'm trying to get info from my C200 using modbus from within Node Red. I need the data so that my code can decide what to do with the load based on daily solar energy.  The latest register listing I have from Midnite is "MidNite Solar MODBUS Network Spec. Rev C.4 --- Dec 9, 2013" and it doesn't seem to be helping.  I am able to read the register values into Node Red.

For example, it tells me I can get the C200 charge state from the MSB and LSB at register 4120.  (I think this is float, absorb, bulkMPPT, etc).  When I use table 4120-1 and 2 the states I get are not the same as shown on the C200 display.

Any suggestions.


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Re: Modbus registers list
« Reply #1 on: October 26, 2021, 01:19:23 PM »
look on the open source topic on forums here.
Graham knows most of those modbus addresses and I think he discussed some recently in one of the topic there.

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 , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie


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    • ClassicDiy
Re: Modbus registers list
« Reply #2 on: October 28, 2021, 08:19:31 AM »
My Android app uses the MSB of 4120


I read starting from register 4100 for 44 bytes at line 314 then grab the MSB at index 19 (which is register 4120)

« Last Edit: October 28, 2021, 08:41:39 AM by Graham »
Off-Grid Island cottage, Lac Simon QC Canada
370 Ahrs @ 24V (4 8L16 batteries)
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