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Growatt 24v Low DC cut-off at 21v????

Is there a setting to determine when the generator relay energizes? Even if you don't have a generator connected, maybe that will signal the inverter to stop drawing on the batteries.
 
Hi All,
Further to the above, I have been able to adjust setting 21 on my Growatt to 24 volts in the user mode, however in an off-grid setup when running off Batteries at night, if a high load is used, say 1800 - 200 watts, the Voltage can drop below 24 volts and the system will then shut down to protect the batteries, and requires a full manual restart. The system doesn't differentiate between Batt voltage drop under high load vs sustained sub 24 v battery voltage due to discharge. So I have had to adjust it to closer to 23 volts, coincidentally the LV alarm on the battery monitor does exactly the same thing. I would suspect that's why Growatt has it pegged at 21 Volts in the AGM setting.
 
I cannot change the setting. I followed the '305' reset video but still, the low DC cut off will not switch from 21v.

Has this happened to anyone here?
Do I have a lemon?
Hello solarstuff
I'm having same issue. I can't seem to change low dc cut off no matter what I'm doing. Were you able to figure it out? If so then would you please share with me your methods. Greatly appreciate
 
I have growatt 24v off grid hooked up to two 12v 206ah sok lithium batteries in series. Everything is working fine but I can't seem to change low voltage cut off to 24v no matter what I do. It just revert back to 21v. Would you please share on how to adjust setting successfully?
Thank you
 
I have growatt 24v off grid hooked up to two 12v 206ah sok lithium batteries in series. Everything is working fine but I can't seem to change low voltage cut off to 24v no matter what I do. It just revert back to 21v. Would you please share on how to adjust setting successfully?
Thank you
Did you set the battery type to user mode first?
 
I have mine set at USE
I would set my low voltage cutoff to 24v but then growatt revert back to default 21v.
With the SOK batteries, 21V would be fine. This thread started about AGM and the discharge would be too deep at 21V for AGM. My GW3000 is set for 21.5V, and yes, you can't go to 24V. Tried AGM settings also and it will default to 21.0V
 
With the SOK batteries, 21V would be fine. This thread started about AGM and the discharge would be too deep at 21V for AGM. My GW3000 is set for 21.5V, and yes, you can't go to 24V. Tried AGM settings also and it will default to 21.0V
Comfort knowing it's safe lvc at 21v but also would like to know how to make adjustments should I need to in the future. If you know how them would you share. I want to test growatt
 
Why? What's the difference between use ans use2?
USE2 will not let a user set float at a level you would like. It's fixed based upon the bulk charge voltage setting.

This becomes a problem as the SCC only feeds to the DC bus. When bulk charging completes, the SCC will not pull any power from PV until the float setting is reached. This is why you want the ability to set float around 0.5V lower than bulk. When the float setting is reached, the SCC will put PV power onto the bus, allowing PV to help power the inverter.
 
Thanks
USE2 will not let a user set float at a level you would like. It's fixed based upon the bulk charge voltage setting.

This becomes a problem as the SCC only feeds to the DC bus. When bulk charging completes, the SCC will not pull any power from PV until the float setting is reached. This is why you want the ability to set float around 0.5V lower than bulk. When the float setting is reached, the SCC will put PV power onto the bus, allowing PV to help power the inverter.
Thanks!
 
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