SW4024 - "Dead" Lithium Batteries or is it a CSW4024 Issue?

rpvietzke

Hi,

I have a Schneider CSW-4024 connected to three simplifi lithium 24V 3.8KW batteries, several charge controllers and an Ecogen 6K at an off grid home some distance from my regular house.

This week was plenty cloudy all week and the generator failed to start. Power has been out since Tuesday, but we've been above freezing, so I waited for today to come check things out. It looks like the SW4024 did its job and cut out, but the small LBCO I have for a couple 24V/12V loads did not. The result is my batteries are sitting at 20.5 v or something like that.

I got the generator up and running. (Annual problem of a sticky choke.) and have 220V back to the inverter again. However, the CSW4024 will not start to charge the batteries and in fact my insight home only recognizes the 3xMPPT's and BattMon. It doesn't see the CSW4024 or AGS (which ironically the XANBUS runs through to get to the devices it does see.).

I seem to recall that the CSW4024 may not come on without a valid battery, but I also recall it is supposed to charge from a dead battery. Obviously if the Insight home can't see it, I can't poke around to see what it is thinking.

Any ideas or recommendations?   I guess my next step is to find a 24V battery charger to try to bring the batteries back a bit?

Rob

BB.

Or a pair of 12 volt chargers (or even one to bring up 1/2 the bank, and then charge the other 1/2 the bank)--You do not have to fully charge the batteries--Just enough that they can power the CSW (my guesses).

From the Simpliphi manual, page 26-27 (note I had to edit the cut and past--Double check with actual manual if there are questions--And contact the Mfg or retailer/support if you still have questions):

https://simpliphipower.com/wp-content/uploads/documentation/phi-3-8-m/simpliphi-power-phi-3-8-m-installation-manual.pdf

6.0 – Troubleshooting

If your PHI Battery bank is reaching its Low Battery Cut Out voltage (LBCO), load disconnects or load shedding set points may need to be adjusted.

The PHI batteries are reading extremely low or no voltage:

Programmed settings in the PHI Battery’s accompanying Balance of System equipment should prevent the PHI Battery’s internal BMS from reaching its low voltage setting. However, in the instance that the PHI Battery’s BMS has turned the PHI battery off, the battery will read low or no voltage, and the following steps should be taken to re-set the BMS:

1. Turn off each of the built-in breakers in all of the PHI Batteries in the battery bank*.

2. Turn off the main DC disconnect located in the inverter’s power panel, between the battery bank and the inverter.

3. Turn off the main breaker at the top of the inverter’s AC distribution panel or sub-panel.

4. Wait 5 minutes, for the BMS in each battery to re-set itself.

5. Use a multi meter to take voltage measurements of each PHI battery in the battery bank,to make sure the voltage increased to the minimum voltage necessary for the inverter to turn on. To measure a single battery’s voltage within a battery bank, only the battery being measured has its built-in breaker in the ON (I) position; all other batteries in the bank must have their built-in breakers OFF (0).

6. Turn on each of the built-in breakers in all of the PHI Batteries in the battery bank.

7. Turn on the main DC disconnect located in the inverter’s power panel.

8. Check that all parameters in the Balance of System equipment are programmed according to the relevant SimpliPhi Integration Guide. Failure to do so will damage the PHI batteries and Void the Warranty.

9. To charge the batteries quickly, SimpliPhi recommends using an AC power source to immediately charge the PHI battery bank via the inverter’s charger. However, the PHI batteries will not incur any damage if they are charged using a connected solar PV array via the charge controller. The important aspect of this step is that the batteries re-charge as soon as the BMS has re-set.

10. Turn on the inverter’s AC Input breaker and turn on the inverter.

11. The inverter should automatically self-initiate a battery charge. However, a Force Charge may need to be initiated in the inverter. *This process can be duplicated with PHI battery models that do not include built-in breakers. To re-set the BMS on the PHI battery models that are equipped with Anderson Connectors, disconnect the PHI Battery at the Anderson Connector instead of the built-in breaker.

Hopefully, the integrated BMS protected the cells from going under voltage and causing damage.

-Bill

rpvietzke

Thanks. I actually have tried that procedure and it didn't help. I did manage to cobble together a trickle charger from a 12V power supply and a Solar Converter 12V-24V. It is only putting out .5 amps at 24v, but I'm trickling 24.5 volts to the SimpliFi's and they are taking it now. We're already up to 23.9V in a couple of hours and 

I turned the CSW4024 breaker back on and still nada. The Invert LED comes on (as does the fault light) and the flashing indicator that it sees the AC from the generator comes on after a minute or two, but the insight home never recognizes the CSW-4024 or the AGS. (Insight Home does see the 3 MPPT's and the the BattMon. I am increasingly worried something is not all right in the CSW4024. I can't "see" it to see if something is wrong, however until it starts talking to the insight home.  (No SCP here.)

Frustrated.

Rob

Dave Angelini

Guessing that when CSW shut down (never a good thing offgrid) the charger became disabled and you lost the CSW circuitry that runs/powers the xanbus network. The internal charger if enabled should have come on at 12V+ for the csw4024.

If you are sure that the CSW bat terms got to zero VDC for 5 minutes, or more. You could try using a wall wart to power Conext Home xanbus power. Not sure what make/model mppts you have. I doubt this will work but.  I doubt giving csw a swift kick would fix a welded relay failure, but it did once for me.

You know you should have the SCP and surge protection. Maybe you do but generators that are not working perfectly are a prime source for damaging electronics. As is the Utility grid. 

 I have so many clients that have neither grid or generators,  they just never have electronics damage in home/power system.   Ever!

Crossing fingers and good luck!

rpvietzke

Hey all,

A couple hours after I wrote this last note, the combination of the trickle charge overnight and a tiny bit of sun on the array brought the battery voltage up to 25.5 and voila!!!!  The CSW and AGS came back to life. I was on the phone trying to find a replacement when I heard a little fan noise in the basement and went to investigate.

All I can figure is that the CSW wouldn't restart from LBCO (which is set at 24V) until it was above the "recharge voltage" (which is set at 25.4). I sure wish the software allowed the XANBUS to be powered up at some lower threshold and it allowed the insight home to tell you what is going on, but ultimately, I'll take it. 

Everything is entirely back to normal now. Ran the generator another 4 hours to bring the batteries back to a more normal charge and have had a "regular" day since. We had a 6" snowstorm overnight and this time the generator started when it needed to (2nd cup of Keurig coffee this morning). All seems well.

During all this I jerry rigged a bypass of the Inverter from the generator to keep the furnace, internet and a few plug in lights on. I'll probably do some work to make that easier in the future. It probably also makes sense to have an aux charger that can get to 25.5 around too.

The lesson in all of this, I guess, is make sure you never get to LBCO and be patient in bringing your batteries back if you ever do.

Rob

Dave Angelini

Good job ! The only thing worse than hitting LBCO is doing firmware during LBCO 😉