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General Category => New Product Ideas and Discussion => Topic started by: Biopwr on July 02, 2016, 02:48:11 PM

Title: After 1811 Kid Update
Post by: Biopwr on July 02, 2016, 02:48:11 PM
I updated my Kid to 1811 this spring and have noticed that several times I have seen the Kid screen go blank the back light is on but no data showing and all buttons are inactive. The only way to get it out of this mode is to turn off the Kid and restart. One time it happened on a cloudy day and the other times on full sun days.
I am running 2ea 24 volt 265watt panels and 2ea smaller 120watt panels charging 4ea 6volt batteries with 420amp hr in my RV.
Has anyone had issues like this with update 1811.
Title: Re: After 1811 Kid Update
Post by: Vic on July 02, 2016, 02:56:55 PM
Hi Biopwr,

I cannot comment on that 1811 FW for the KID.

But,  there is a question about your PVs;

What is the Vmp of those "24V"  265 watt PVs?
What is the Vmp the 12 V PVs?

Assume that you are running two of the 12 V PVs in series,  paralleled with single 265 watt PVs.

Most PV modules that are in the 230 - 280-ish watt PVs are 60 cells,  and therefore are usually not actual 24 V PVs ...   just curious.  Thanks,   Vic
Title: Re: After 1811 Kid Update
Post by: Biopwr on July 02, 2016, 03:05:46 PM
The 2ea 265 watt panels are mono panels and the VMP is 30.0 are in parallel and join the other two at a combiner block down by the kit
The 2ea 120 watt panels I dont have the VMP on them they are in parallel and join the other two at a combiner block down by the kid
Title: Re: After 1811 Kid Update
Post by: Vic on July 02, 2016, 04:36:02 PM
Thanks Biopwr for the reply.

You are probably not seeking optimum power from your system,  perhaps just running what you had on-hand.

A further assumption is that the 120 W PVs ARE true 12 V PVs,  and probably have a Vmp of about 17.7 - 18.2-ish volts.

If so,  you may be loosing a bit of PV production,  as that probable voltage difference might approach about 20%.   At times an MPPT CC may have a bit of an issue finding the Maximum Power Point with this amount of variation,  if the assumption of the 12V PV is fairly close.

Is this a 12 V system?   Is this system operating up to your expectations?

Thanks,   Vic
Title: Re: After 1811 Kid Update
Post by: niel on September 10, 2016, 06:49:33 PM
no doubt vic is on the right track asking these questions of you, but from what i see you have a problem with the setup for either 12v or 24v battery systems. further, you indicate that you've paralleled all pvs and no doubt this is a mismatch. the 12v 120w pvs could possibly be in series to get a 30v+ vmp for a 24v battery system, but the 2 265w pvs are a bit low for a 24v battery system. to a 12v battery system it could work with the 2 265w pvs in parallel and paralleled with the 2 120w 12v pvs in series, but you are not converting all of the solar as you've exceeded the capacity of the controller. it's a bit too high on the 24v battery system too so you need another cc to handle the power.

added- the screen blanking i'm not sure if the mismatching and over current have anything to do with that or not.