SG - WAY OFF THE CHARTS!

morpho · December 2015

Hi,
Hoping someone will have a word of advice on my issue.

I found out late morning that my battery monitor kicked the bucket on me 3 days ago. (Magnum ME-BMK. )
Also noted the system was in float. (impossible as it was too early in the day.)
I put it into force bulk...it rolled into absorb right away. (which would have been normal for that time of day)
Checked the SG...not charged, but close.

Ok...I have been operating without the BMK for 2 days now, so I am looking under the hood daily to check things manually.
I get home today and open her up, take a sample and the bulb is floating high...real high...like off the chart high. (normally I see it settled at just barely 1.260)

I look at CC...it says floating...it had the 3 hours of absorb and about an hour of float under it's belt. The norm.

Any words of advice?
Thanks.

Outback Flexmax 60 CC
Magnum MS-PAE Inverter
Magnum ME-RC50 remote
ME-BMK batt-monitor
8 - US 2200xc 232amp hour (48v)

inetdog · December 2015

Do you know from the manufacturer what the nominal fully charged SG is for their batteries?

PS: Some manufacturers also ship a "tropical" variant with a lower SG.

morpho · December 2015

Hi Inetdog
No, I don't know to be honest...but these have been in service for 5 years and have performed in a steady and reliable way...until today.

When I say the reading was off the chart...I mean the bottom of the gauge/scale was way out of the electrolyte by about 1/4 inch on every cell.

morpho · December 2015

Dug into my files and the battery should have an SG of 1.270 minimum. I have never hit that mark, regardless of absorption times or running an Equalize on the batteries etc.

morpho · December 2015

mike95490 · December 2015

What was the thermal adjustment ? The temperature affects the measured density.

Surfpath · December 2015

Hi Morpho,
Could you give us a little more on your system specs. How do you charge these batteries? Solar? How many Watts?
5 years - not bad. According to the specs (see link below). At 30% depth of discharge it's anticipated they will last ~5-6 years.

Other factors impact this timeframe. What has been the typical SOC at the end of the day if they were not getting up to the recommended 1.270 mark? How long have you been absorbing them, and at what voltage?
Best,
SP

http://usbattery.com/wp-content/uploads/2015/02/usb_2200_data_2015_WEB.pdf

morpho · December 2015

Hey Mike,
The battery bank was reading 83ºF that day.... which I can appreciate as they were obviously WAY WAY over-charging. So, just a scratch past the baseline commonly used . Typically I fall almost spot on at 80ºF
But I hope temp wouldn't float the bulb almost right out of the electrolyte!

Hey Surfpath,
- It's PV charged (3kw)
- Typical discharge is 15 - 20% (this has been - more or less - religiously maintained)
- The typical SG reading at "100%" SOC is 1.260 - 1.265
- Absorb has been 3 hours at 58.8 volts.

Thanks folks!

Mountain Don · December 2015

Does it float to 1.0000 in plain distilled water? Temperature corrected too

morpho · December 2015

Hold the presses!
Ok....so I went to check the SG this morning before the system turned on and I spotted that the bottom of the glass bulb was broken. A wedge was gone and the weights were coming out of the bottom. So there you go....sigh....nobody said it wasn't going to be an adventure!

Thanks.

zoneblue · December 2015

Aint life fun. Back in my miltary days, i was like 16 years old out on this exercise in the mountains. It was a total white out, everybody was getting cold, and the commanding officer, hes on at me to make a quick decision about our bearing off the top of this peak. My compass was giving me a reading that just didnt feel right, and i hesitated. So finally he just charges off in the direction that i also felt was right, but was 90 degrees off the course the compass said. Several hours later finally admitting the error we all returned to the top and followed the compass and quickly found the correct spur. Turned out we had kind of cork screwed our way up that hill in the mist, and while i thought my compass must have got demagnetised somehow, it was actually our eyes tracking the light as we climbed that was at fault. So it can go both ways!

morpho · December 2015

Hi Zoneblue,
Why didn't you just use your smartphone!!??!!?? (tongue planted firmly in cheek)
Ya, I ran out to the hardware store first thing this morning and picked up a new Hydrometer. Then I proceeded to question if it was accurate. Winding my way around the mountain in the mist.

Thanks everyone.

SG - WAY OFF THE CHARTS!

Comments

Categories