Yeti Pro 4000 Nominal Voltage

scottnichol67
scottnichol67 Member Posts: 6 ✭✭

So, I had an incident recently where, after sitting unused for a few days my Yeti 4000 started beeping with the CHGMONERR warning. There was also an alert telling me there was a battery fault. The only way I could get the unit to power on was to plug the AC charging cable into the back of the unit. Even with it plugged in and powered on, the inverter wouldn't power the AC outputs.

Device Info menu showed me that the voltage was at 41.1 V, even though the front panel was showing 100% charge. I read some other posts here where it seemed like others were reviving the Yeti with a direct DC charge. So, I pulled out my Nomad 400 panel and plugged it in. Almost immediately the voltage started to rise. Then when the voltage got somewhere into the 50s, I was able to power up the AC outputs.

I plugged in a nearby shop vac and started it up. It ran for a few seconds, then shut off and the Yeti showed 0% charge instead of the 100% it showed just seconds ago. So, it seems to me that after sitting idle for a few days, the voltage drops and the unit doesn't display the corresponding drop in %-charge.

I guess my question is, what is the nominal voltage for the unit? Mine is currently holding steady at 53.3 V. Also does the current firmware version 1.5.8 do a better job at either reflecting the voltage drop on the front panel through the state-of-charge %, or does it better maintain the voltage while plugged into AC input power? I would think that this would be essential for emergency preparedness where the unit can sit idle for weeks until needed and the voltage could potentially drop over time.

Comments

  • Learning
    Learning Member Posts: 1 ✭✭

    I had a similar issue. Charged 100% on A/C, let it sit for weeks, and then the unit wouldn’t turn on without being on A/C. Had the CHGMOSERR and BATTERY FAULT errors, internal battery temp issues (showed -459 on the app). The firmware wouldn’t even update. Goal Zero shipped me a 600w power supply (no charge). After sitting on that power supply for 24 hours, everything was working fine. I was able to update the firmware and use all outputs without issues.

  • scottnichol67
    scottnichol67 Member Posts: 6 ✭✭

    @Learning Thanks for sharing your experience. This is very consistent with what I've seen over the past couple of weeks. Mine sat idle for the past few weeks and was holding steady at 90% charge. But yesterday I tried to use it with my shop vac in the garage and as soon as I turned on the AC ports and started the vacuum, the state of charge dropped to 78%. So, it feels to me as if the system doesn't do a good job of monitoring its true state of charge.

    I have the same 600V power supply that they sent me and maybe over the course of the next couple weeks, I'll leave it plugged in to the Yeti and see if it does a better job at maintaining readiness. Ideally in the spring, I will add some more solar power to the house and use that to maintain the charge on the unit.

  • Ely
    Ely Member Posts: 39 ✭✭

    LFP haves a higher self drain as NMC. I think the system does not recognize the self drain und shows you a higher SOC as it is.