My charge controllers are skipping absorb intermittently, I have them set for fixed 1 hour absorb with tail current disabled , they are hooked up to a pair of multiplus 2 in split phase with cerbogx and lynx. Bus bar ,they have rj 45 Victron cables , they did work fine for 4 days then they started skipping absorb and sometimes going into absorb but not for specific time set of 1hour .
Do your batteries have systems comms? How else is the systen programmmed? Are you on grid or off grid?
Lithium batteries with no com ,they were going into absorb at one time ,but lately intermittent ,
I’m using the system as off grid I do have grid power but don’t feed out into grid , my multiplus 2 are programmed as a split phase 240 volt with phases offset 180 degrees , my charge controllers are connected to ve can system using Victron rj45 cables , hooked to cerbo gx ,inverters are also hooked up using Victron rj45 cables to ve buss , I do have a links shunt bus bar . They were programmed using veconfigure software using windows computer ,all software up to date, all charge controller settings were done using Victron connect ,I did both settings the same in each charge controller as I’m not sure who is the master controller , no battery com connection ,they are lithium phosphate batteries.
They should be in the ve can. And have a terminator in one end.
Ve bus is for inverters.
They do have terminator at the last charge controller , I was looking at the history of charge controller on Victron connect and absorb time varies and sometimes right on the 1hr time that I set in controller settings, yes charge controllers are plugged into ve can and inverters ve buss ,sorry made a mistake on earlier post, I did power down both charge controllers at night and powered them back up and they worked great for 3 days with absorption exactly at 1 hour, also noticed data for charge controller in VRM advanced shows no absorption time that day but in Victron connect it shows 1hr absorption time for charge controller , I wasn’t there that day so not sure if it actually did a absorbtion time , also I updated my VRM app yesterday maybe Victron fixed this in the update . I will see in the next few days what happens.
No worries. It happens i just wanted to be sure.
And sun /day length was good?
Sometimes that can also be a factor, as well as loads then discharging the battery as well.
I’m going to pay attention to the sun hours and loads in the next few days , today was weird it was in absorb for 1.5 hours , I was assuming when you set the charge controllers to fixed ,it shouldn’t go over that fixed 1.0 hours , I did notice with my loads the voltage dropped below my absorb set voltage (about .5 volts )for a bit . But I was under the assumption if you set to fixed 1.0 hours that’s the maximum time spent in absorb . Also noticed the max max pv watts was off from what charge controller measured 4860 watts compared to VRM max watts 3090 watts , I know VRM does updates every 15 minutes in my setting ( now changed to 5 minutes ) but it was sunny for at least 1/2 hour or more ,also weird it’s inaccurate on one charge controller only . I did see the wattage on both charge controllers on VRM live and they matched charge controllers info on Victron connect app .
Thanks for your help !
Update today they skipped absorb ,full sun today for 5 hours ,batteries were around 48% full , so they were charging with full power from the panels 8000to9000 watts there was med load from the inverters maybe 3000 watts from total capable 10000 watts . I’m starting to think there is a interference from wires close to rj45 com cables , I will try separating them and see what happens,
UPDATE FEB 14TH I replaced charge controller wires from awg 4 18 strand t90 (90 celcius rating )95 amp rating to 2awg 620 strands. 250 amp rating 600 volt ,105 celcius and today they worked perfectly from bulk to absorb 1 hour what I set them at , then into float . I will see what happens in the next few days . I did check voltage drop on old t90 awg4 wires and ripple using a fluke 88 multimeter all seemed good . Voltage drop was .150 volts on positive wire from charge controller to buss bar and .049 volts on negative wire from charge controller to buss bar ,note positive wire goes through a 100 amp breaker , ripple was .172 volts , I didn’t recheck voltage drop or ripple on new wiring set up , I might in the next few days .
Pulling the cables and replacing them with larger cables may have reset the solar charge controllers.
Do you have the solar charge controllers in a Victron Bluetooth Network and also connected to a Cerbo GX (wired)? If so, remove them from that network. It’s not necessary and can create issues like you’re seeing. I can’t explain it, but I’ve seen it on my system with two Smart MPPT 150/35 connected to a Cerbo GX.
Yes charge controllers are wired to cerbo gx with rj45 cables and on Bluetooth ve can ,i previously(before wire updates) had unplugged rj 45 connectors from cerbo gx and removed them from Bluetooth ve can and they still intermittently shipped absorb , I’m hoping they work properly like yesterday , today it’s not the best day for solar ,still in bulk mode since this morning ,batteries are almost full 96%soc , and almost at absorb voltage . Thanks for your info . UPDATE AS OF FEB 17TH so this is 3 times charge controllers have gone to absorb ,2 times exactly 1 hour and once 1: 13 minutes ,this day was cloudy and I noticed they drooped slightly below absorb voltage setting so this is why they were in absorb for a extra 13 minutes . Let’s see in the next few days ,it’s looking good .UPDATE AS OF FEB 18TH , WENT INTO ABSORB TODAY FOR 1HR AS I SET IN SETTINGS ,LOOKING GOOD, UPDATE SO FAR SO GOOD AS OF FEB 20TH , IM GOING TO SAY this is resolved . Thanks everyone
There are a few threads here and on DIYSolarForum.com where removing the solar charge controllers from the bluetooth network solved the problem. Mine are now only on the hardwired network to the Cerbo GX.
Thanks for the info 
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