Blue Sky 3024dil cut in voltage

[pianotuna]

Hi All,

My solar panels were covered in snow this year.

The result was the house batteries got down to below 8 volts.

The sophisticated charger in the Blue Sky refused to send power to them.

The dc to DC unit finally got the voltage up high enough that the Blue Sky could log on. it happened at about 11.9 volts.

[StirCrazy]

pianotuna wrote:

I've seen charging at 3 inches of powder snow, approximately 0.3 of an amp. However this was hard drifted. Heavy wet snow would be even worse.

As I'm 75 and a long range planner, I'll probably not get my SiO2 jars. My plan is to sell the RV at age 80--or give it away to family. I can't justify spending $4000.00 for 700 amp-hours of battery bank. Not when I can get over 500 amp-hours of reconditioned telco jars for $1 per amp-hour.

that makes sense, why spend that money if you plan on not using them very long

[pianotuna]

wing_zealot wrote:
Why 3 posts about the same thing? Wouldn't 1, with continuing dialogue as you see fit suffice?

Because I wanted folks to see specific results for each of the aspects.

In the past I have done several what I call "back yard" experiments.

Most of us don't run the batteries dead flat. Knowing that AGM telcom jars can be rescued may save someone from needlessly buying a new battery bank. That deserves a thread.

Most RV's don't yet have a dc to DC charger--so the results needed their own thread. Hopefully it will give some information to help folks to make a decision on whether they need one or not. Knowing that the dc to DC charger works even on a totally flat battery is good.

There is no information about the cut in voltage on the Blue Sky Charge controller. That is a good number to know--so again a different thread.

I do agree they overlap.

[pianotuna]

StirCrazy wrote:


How thick was the snow Don? Im curious as I have seen charging through a bit of snow and want to know how much it takes to shut it down.

If you would have had LiFePO4 your BMS would have shut them down and protected them from over discharge you know ')

I've seen charging at 3 inches of powder snow, approximately 0.3 of an amp. However this was hard drifted. Heavy wet snow would be even worse.

If I had Li batteries they would require me renting a shop to warm them up before I could safely charge them, if the bms had shut them down. Since the starter battery was also dead that would mean towing the RV. Many of the Li formats I've investigated require a high voltage to switch the bms back on. So I'd probably require a special charger for that purpose.

As I'm 75 and a long range planner, I'll probably not get my SiO2 jars. My plan is to sell the RV at age 80--or give it away to family. I can't justify spending $4000.00 for 700 amp-hours of battery bank. Not when I can get over 500 amp-hours of reconditioned telco jars for $1 per amp-hour.

[wing_zealot]

Why 3 posts about the same thing? Wouldn't 1, with continuing dialogue as you see fit suffice?

[pianotuna]

CATraveler,

I already have a full disconnect switch. This the first time in 13 years there has been an issue.

Once I got to shore power, the inverter/charger started in at 62 amps, after one hour that had risen to 84 amps, in bulk mode. Both those numbers were supplemented by over 10 amps from the solar panels.

After 7 hours that dropped to about 59 amps no longer in bulk mode.

By 11 hours that was down to 10 amps in float mode.

After 15 hours charging is at 1 amp float mode.

The load support is working well, so I'm guessing the battery bank recovered.

[StirCrazy]

pianotuna wrote:
Hi All,

My solar panels were covered in snow this year.

The result was the house batteries got down to below 8 volts.

The sophisticated charger in the Blue Sky refused to send power to them.

The dc to DC unit finally got the voltage up high enough that the Blue Sky could log on. it happened at about 11.9 volts.

How thick was the snow Don? Im curious as I have seen charging through a bit of snow and want to know how much it takes to shut it down.

If you would have had LiFePO4 your BMS would have shut them down and protected them from over discharge you know ')

[CA_Traveler]

Perhaps a full disconnect switch on the battery post is in your future?