Bulk float absorb...repeat

[Isfry]

Forgive me, my memory isn't what it used to be, and I have upgraded a couple of components since this time last year (all new battery bank, second inverter stacked). Nevertheless, my recollection was my batteries would get close to 100% SOC, the float charge would then run for two hours and then the absorb would run for two hours (assuming I was at or above 60v.)
Lately I have watched as the batteries get up to full in the morning (bulk charge?) then watched as the two hour float charge begins and completes, with voltage comfortably above 54v. My absorb charge timer stays at 2:00, and never starts, despite the fact that I hover for over two hours at over 60v after the float completes.
Any ideas? Suggestions? Need more info? Thanks in advance.

[raysun]

The normal sequence of charging is Bulk (to about 80% SoC), followed by Absorb (to 100% SoC), and finally Float (to maintain the battery at 100% SoC until there is no further charging current.)

If the charge cycle is different than that, there is likely a misconfiguration in the Absorb Voltage, Absorb Time, and/or Float Voltage.

If all the above parameters are set correctly, check the Re-bulk voltage, it may be set too low.

[Isfry]

Absorb is set at 60 v (2 hours), float is set at 54 volts (2 hours), rebulk is set at 50 volts.
Is that wrong?

I got the absorb and float parameters from the rolls battery manual, reading the column for a 48v setup with regular charging. I don't see a suggested rebulk voltage anywhere in that manual. The 50v setting for rebulk may have been from my original setup (which I didn't do) on install, four years ago.

[Mike Curran]

Don't forget, the VFXRs also have a refloat setpoint that should be set above your rebulk setting. My VFXR settings are shown below, and my rebulk is 24.4 (48.8 equivalent on 48V system), with refloat at 25.0 (50V equivalent).

There's no float time setting on my FM80s, is there one on your FM100? If not, I thought your FM100 would try to maintain float indefinitely, same as my FM80s.

It's not clear to me exactly what your system is doing. You say,

I hover for over two hours at over 60v after the float completes.

How could your system be hovering at over 60V after float, when float is set for 54? If you can post a screenshot like this for your system (showing battery voltage, not SOC) it would help us understand what's going on.

[Isfry]

I'm not hooked up to the outback web program at present for unrelated reasons, so I cannot post any such screenshot. Hmm...

When I push the charger button in my Mate3 it says the following:
Inverter charger status
Battery 54.5v Charger control ON
Absorb 60.0v 02:00 remaining
Float 54.0v 02:00 remaining

However, when I go to the battery charger settings I don't have an option on float time, either. I can only adjust the voltage.

[Mike Curran]

As a reference point, right now (end of day) my float & absorb time remaining both say 0:00. What time did you get these 02:00 remaining readings?

[raysun]

I'm not hooked up to the outback web program at present for unrelated reasons, so I cannot post any such screenshot. Hmm...

When I push the charger button in my Mate3 it says the following:
Inverter charger status
Battery 54.5v Charger control ON
Absorb 60.0v 02:00 remaining
Float 54.0v 02:00 remaining

However, when I go to the battery charger settings I don't have an option on float time, either. I can only adjust the voltage.

Note this is the Inverter Charger status.

The inverter charger specifies Float Time. The FlexMax charge controllers maintain float as long as the sun permits, and do not specify Float Time.

The two charging systems work autonomously, but should be adjusted to work in sync.

[Isfry]

When I wake up in the morning both the float and absorb timers say 2:00. The float timer starts ticking down once I get close to 90% SOC or so. The absorb timer (I think) used to start counting down after the float timer finished, which may have been improper to begin with. Nonetheless, the absorb timer never budges now, so I end up with a float timer reading zero and an absorb timer still at 2:00 at the end of the day.

[Isfry]

I have a different battery charger sub menu under the inverter heading that lists the following:

Battery Charger
Absorb Voltage 60.0 VDC Time 2:00
Float Voltage 54.0 VDC Time 2:00
Re-Float Voltage 50.0 VDC
Re-Bulk Voltage 50.0 VDC

No time is listed after either of the latter two, but I can adjust either Re-Float or Re-Bulk Voltage here, if I knew what to reset them to.

[ralphday224]

I just checked mine...float voltage 53.6v, 24/7 duration. Once bulk and absorb are done it holds float 24/7 unless charger is turned off. Time is adjustable.

[raysun]

When I wake up in the morning both the float and absorb timers say 2:00. The float timer starts ticking down once I get close to 90% SOC or so. The absorb timer (I think) used to start counting down after the float timer finished, which may have been improper to begin with. Nonetheless, the absorb timer never budges now, so I end up with a float timer reading zero and an absorb timer still at 2:00 at the end of the day.

The sequence described for Absorb and Float is exactly the opposite of normal operation. TBH, I have a hard time envisioning how its even possible.

There are three charging sources in the system: the 2 inverter chargers and the FM100 charge controller.

All three need to be calibrated to the battery voltage.

All three need charging profiles that are compatible with the battery and with the functioning of the other chargers.

Something is very strange here.

Perhaps start by listing the battery charging parameters for all three chargers.

[Isfry]

I had a guy come and stack a second inverter last year, and prior to that the charging all seem to be functioning properly. I'm going to call him and have him come up and see if maybe there's something above my pay grade (which isn't very high) that needs to be tinkered with in the control room itself, outside of the Mate. I'll post whatever solution is achieved.

[Isfry]

UPDATE (for those who have nothing better to do than worry about my problems...)
I had the inverter wiring checked and was told all is correct. The original battery specs I punched in were from the Rolls manual for my S6 L16's. As an attempt to fix the absorb problem, I changed them to the default numbers from the Outback manual. Still no absorb cycle happening. The guy who came up (who seems to know his stuff, better than me, at least) said the Rolls numbers were too high and the default Outback numbers were too low. He tweaked a bunch of them to be somewhere in the middle. Moreover, he identified one error I had made, which was I was adjusting the battery numbers for one inverter (master) in port one without switching to the other inverter (phase master) in port 7. (I know, I know, stupid mistake, but I am new to inverter stacking so give me a break.) I hoped that after he left the next day would reveal an absorb cycle in advance of my float charge, but no such luck. I am at a loss, and am still not hooked back up to Opticsre, so I can't provide any more data than I have, but am more than happy to answer any questions that may help round out the picture. Anyone who thinks they have a simple change that might start my absorb cycle again, I am willing to try. I just bought 16 new batteries last year for the first time and really want to maintain them properly so as to avoid dropping that chunk of change again any time soon. Thanks in advance.

[Mike Curran]

Is there a reason why no Optics? Because a screenshot of your system dashboard from Optics would help (me, at least) understand what you're describing. No pressure, more info = better solutions.

[Isfry]

The optics problem is because the Cat5 went outside along the foundation around the house and then back in for the router connection. I'm building a bedroom and dining room addition, which expanded the foundation beyond the length of the Cat5. I could temporarily run a short Cat5 indoors and just get a snapshot, if that would help, but I can't leave it plugged in as I have two small children and two big dogs and a small space.

Also, if it's relevant, when I push the charger button on my Mate3 and then push the button under charger status it says charger ON and then Bulk and Float Charge Enabled below that. I don't recall if it ever said anything about absorb charge there. Is it possible it's turned off?

[Isfry]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in. I tried a second cable to see if the cable was bad but same result. OpticsRE is "enabled" in the systems menu on my Mate, and I turned on serial data stream, which was disabled, thinking maybe that was the data I needed to be streaming. As usual, my hamhanded attempt to fix one problem has unearthed (or caused) another...
ugh

[raysun]

don't recall if it ever said anything about absorb charge there. Is it possible it's turned off?

The only way (normally) to disable Absorb is to set Absorb Time to 0H. That actually disables Bulk and Absorb at the same time, skipping directly to Float.

[raysun]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in.

Is this the same Mate as was originally registered with OpticsRE, or a replacement unit?

When the PORT key is pressed while on the main status screen, does the Mate have a valid IP address for your LAN?

[Isfry]

don't recall if it ever said anything about absorb charge there. Is it possible it's turned off?

The only way (normally) to disable Absorb is to set Absorb Time to 0H. That actually disables Bulk and Absorb at the same time, skipping directly to Float.

absorb was set at 2 hours ( I think that was the default). Based on my setup the guy who came to tinker with it lowered it to 1.6 hours for some reason. It still doesn't start.

[Isfry]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in.

Is this the same Mate as was originally registered with OpticsRE, or a replacement unit?

When the PORT key is pressed while on the main status screen, does the Mate have a valid IP address for your LAN?

Same Mate. Never changed it. Which Main status screen? I tried pushing port at the main screen, nothing. I tried pushing it at the main Mate menu, nothing. Not sure which screen you mean. Sorry. I know it's probably like trying to teach a child calculus...

[Isfry]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in.

Is this the same Mate as was originally registered with OpticsRE, or a replacement unit?

When the PORT key is pressed while on the main status screen, does the Mate have a valid IP address for your LAN?

In case it's relevant, both of my VFXR3648A inverters are using firmware update 001.006.063. Should I update that? I see that 001.006.067 is newer.

EDIT: Nevermind. Puerto Rico only.

My Mate appears to have the newest firmware update, as well.

[Mike Curran]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in. I tried a second cable to see if the cable was bad but same result. OpticsRE is "enabled" in the systems menu on my Mate, and I turned on serial data stream, which was disabled, thinking maybe that was the data I needed to be streaming. As usual, my hamhanded attempt to fix one problem has unearthed (or caused) another...
ugh

Don't worry about it, I just thought if it was something simple we could get it going. Sorry if I've sidetracked your main issue.

[Isfry]

So I tried to hook a thirty foot Cat5 across my house into the modem and the Opticsre site says my system is offline when I log in. I tried a second cable to see if the cable was bad but same result. OpticsRE is "enabled" in the systems menu on my Mate, and I turned on serial data stream, which was disabled, thinking maybe that was the data I needed to be streaming. As usual, my hamhanded attempt to fix one problem has unearthed (or caused) another...
ugh

Don't worry about it, I just thought if it was something simple we could get it going. Sorry if I've sidetracked your main issue.

No. Not at all. I'm trying to get you more info so you might be able to help with the main issue. The optics thing is bugging me, now, too, but I still am mainly concerned with the absorb charge anomaly. I wish I could give you (and others) more data. No sorries, tho. Thanks for the help.

If you have any suggestions on what setting might have gotten changed that disabled the optics (despite the fact it's "enabled") I'm all ears.

[Isfry]

UPDATE: I spoke with a guy at Rolls for almost an hour, who advised me to put the absorb back at 60v but to set the time at 5.2 hours, based on the size of my array, which he also recommended (strongly) I increase (double.) RaySun had told me a while back to do the same. Anyway, let's see if the absorb even starts. Today is cloudy so I'll have to wait til tomorrow to see if this helps. I also think I will need to use my generator to help boost the charge a couple hours before the pv really kicks in. We'll see...

[raysun]

UPDATE: I spoke with a guy at Rolls for almost an hour, who advised me to put the absorb back at 60v but to set the time at 5.2 hours, based on the size of my array, which he also recommended (strongly) I increase (double.) RaySun had told me a while back to do the same. Anyway, let's see if the absorb even starts. Today is cloudy so I'll have to wait til tomorrow to see if this helps. I also think I will need to use my generator to help boost the charge a couple hours before the pv really kicks in. We'll see...

Since you have (two) inverter chargers and a pv charge controller, use all in tandem to get through a full charge cycle.

Set the Absorb Voltage on the Flexmax to (the recommended) 60V, and Absorb Voltage on the inverter chargers to 56.6V. Set Absorb Time the same on all chargers.