What's the best way to end Absorb or EQ through Modbus?

[stephendv]

Hi,

I'd like to end both Absorb and EQ programmatically from another device.  The manual states that setting the absorb timer would have unpredictable results... so which value can I change to get predictable results 

[SolarMusher]

To End Absorb with a classic you need to download the last firmware, just click on firmware on the midnite website and follow the process. It takes +-one minute to stop Absorb. Automatically start an EQ is not always a good idea as you can't control it, manual is better.
Hope this help,
Erik

[stephendv]

Ok, but which register do I need to set through Modbus to end it?

[Vic]

Hi Stephen,  and Erik,

Near the end of the newest manual for the Classic,  there is a listing of all of the ModBus-accessible Registers,  and the definition of their functions -- Manual Here:
http://www.midnitesolar.com/pdfs/classicManual.pdf

In my opinion,  the best one to try using to end any of the charging functions is on Page 91,  Table 4160-1 -- ForceFloatF,   which appears that it MIGHT Force the Charge Stage to Float.

NOTE:  This is only from reading the manual ... I have not tried ANY of this.  Some of these functions might not be yet implemented.  AND there may well be a ModBus box that is a programmable interface that would be a good starting place for us that want to try this.

Those who really know will chime in on this.  Thanks for bringing up this topic,  as it is something that I had wondered about playing with myself,  altho there is some risk  when getting started playing with some of these control functions,  as if some "slight" mistake is made,  the results could be unpredictable as well.

YMMV,  All that I really know,  is that I know nothing.  Good Luck,  Thanks,  Vic

[stephendv]

Thanks Vic, I'll give the forcefloat a try when my classic arrives. 
Can anyone from midnite confirm that changing values such as absorb time, absorb voltage, float voltage is OK to do through modbus while the controller is running, without risking damage?

[boB]

Thanks Vic, I'll give the forcefloat a try when my classic arrives. 
Can anyone from midnite confirm that changing values such as absorb time, absorb voltage, float voltage is OK to do through modbus while the controller is running, without risking damage?

Yep.  Should be fine while on.   Just follow the directions.

The main thing to keep in mind is to NOT write ones (1) to bytes and bits that are undocumented or reserved.

Keep us posted !

boB

[stephendv]

Yep.  Should be fine while on.   Just follow the directions.

The main thing to keep in mind is to NOT write ones (1) to bytes and bits that are undocumented or reserved.

Keep us posted !

Thanks boB, will do.