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The Open Source software/hardware corner => General info => Topic started by: tomartig on January 31, 2022, 05:41:57 PM

Title: Adjusting the Day Light Nite Light sensitivity
Post by: tomartig on January 31, 2022, 05:41:57 PM
Hello,

Newbie here.  I have a Classic 200 and want to use the daylight function on Aux 1 to turn my inverter on and off so I can power some loads during daylight hours with solar but switch them back to shore power in the evening.  The problem I have is the daylight mode is set to go low when the PV voltage falls below the battery voltage.  My battery voltage is 12 volts and my PV volts is around 100 volts.  I have 6 250 watt panels wired up in 2 sets of 3.  The problem is that my PV voltage doesn't drop that low until its almost totally dark and it has been hours since I have had enough watts to run my load.  I found one reference to a place to adjust the sensitivity at Modbus Address 4159 and it looked like a memory location to put a value in that is added to the battery voltage.  I am not familiar with how to modify these values. I am running Classic Status 4 Plus and downloaded his utility to read Modbus locations but I am not sure how to write to them.  This value is not under his classic settings tab.  Any suggestions would be appreciated.
Title: Re: Adjusting the Day Light Nite Light sensitivity
Post by: ClassicCrazy on January 31, 2022, 06:09:12 PM
Have you thought of using other aux functions to turn your inverter on and off ?
If you have a Whizbang you could think about trying SOC % . With SOC control you know your batteries will never be below a certain SOC value.
There is also diversion and waste not on Aux 1 .

Larry
Title: Re: Adjusting the Day Light Nite Light sensitivity
Post by: boB on January 31, 2022, 08:57:31 PM
PV trigger, possibly ?

To make sure it does not trigger on a MPPT sweep or something short lived,  just make the Aux 1 PV Trigger attack time/ delay time (whatever it's called ?) to be longer than a few seconds.   Maybe even a couple of minutes ?
And the HOLD time to be a couple minutes also.

Set the voltage lower than you would ever expect it to go.  Lower than what you normally see it go anyway.  Maybe 20 volts ?

See if that works OK.

This in addition to what Larry is suggesting.

boB