Starting off with 2 new Surettes, but cutting my bank in half to try and make this work this time

Freewilley · August 2017

Thanks Vic and all posters.

I am elated.
Finally the system is working as expected. I could NEVER run absorb cycles for at least 3 years.
Now I have fullly charged the new batts and the old ones are just as high as if I ran an EQ cycle.
And my strategy of babying the new batteries is working, although with hiccups.

If there was a way to reset the CC to run a new absorb cycle in a day, that would be fantastic. (I imagine I could reboot the CC, but that is quite the hassle, daily).

Finally I can lay off the babysitting and EQing....thank you Surette for indulging me and replacing 6 batteries over the last 4 years without any arguments!

Vic · August 2017

Hi Freewilley,

Sounds like great progress, congratulations!

What is the purpose of wanting a second Bulk/Absorb charge in a single day? ... OH, right, probably for the second string?

When you are there, you can go to the Misc menu and Force Bulk.

Later, Vic

Freewilley · August 2017

I have used the force bulk many times. It never did work to reset. I will try it again with the new setup, but it just reverted to float or bat full before.
I think I DID try it again when I posted the question and it did not reset....we shall see tomorrow when we get some sun.

Horrible solar season up here, rain and cloud like I have never seen.

Vic · August 2017

Hi Freewilley,

Seem to recall, that if CC EA is being used, that there was some issue ... forget. EA should not be used by the CC until the CC is in Absorb, and, if the battery needs a charge, the transition to Absorb should not be that rapid ... been more than five years since MX-60 were used on a regular basis, here.

Will ruminate on this ...

Later, Vic

Freewilley · August 2017

I am so bored I started reading the 3 year old threads when I first sought help.
Actually, it is a good exercise as there are SO many things to consider...anyway, one post about Rebulk setting was responded by you and Cariboocoot.
You told me the MX setting for Rebulk was too low at 9 amps and get it to 12. I just looked at the MX and the rebulk was 6.
Possibly that is why it would not rebulk when a forced Bulk?
Anyway, I will not look for change in behaviour.

Freewilley · August 2017

FM 60 VBatt calibration 12. 2 +.1V
MX60 VBatt calibration 12. 2 +.2 V

Is this correct, or how do I check this setting?

Vic · August 2017

Freewilley,

Personally, would change Calibration settings by using my very accurate, high quality Multimeter. Changing Calibration on CCs is really saying to the CC, that you KNOW, based upon your very accurate meter, that the CC is a bit off in its accuracy.

Calibration changes will affect ALL voltage-regulated charge stages, so, it is good to only change this when you KNOW that your reference (meter) is quite accurate.

For the purpose of trying to get CCs to share current well in voltage-regulated charge stages (mostly in Absorb), then would just make small changes in the Vabs setting (for example).

If the change that you have made in the Calibration is only 0.1 V, then making the change in the Calibration should be fine.

ReBulk on OB and MidNite CCs is a voltage setting where the additional Bulk stage will begin on any single day. For ReBulk to be initiated, the battery voltage must at or below this set value for some small period of time (IIRC).

... Still trying to remember what was the issue with Force Bulk, and having it stay in, or appear to stay in Float.

What is the reason that you need to Force Bulk?
Is it because you have switched to the second string of batteries ??

Vic

Freewilley · August 2017

Yes, using the 2nd string properly would mean some days starting a 2nd absorb.
I have not made a change in calibration...those are the settings I read.
I have finally bought a clamp meter and have started taking readings....now I am going to Youtube to learn how to use it. Advice on where to test is welcome.

Also, I overnighted for the first time using my new string. I was fully charged, 1.265 at 630 pm (no solar). At 930 pm (bedtime for old farts) pilot cell was 1.250 and at 6am 1.205. So that is a good showing of what I use overnight....
I switched to all four and turned genny on. At 830 system was absorbing and pilot cell on both strings was 1.225. Voltage on CCs were 14.9. However I tested voltage at both strings and the new one was 14.8 and the old 14.2.
Tested SGs on the old string and my worst cell (middle of course) was 1.180 and others were approx 1.225
I conclude that charging both strings together is not really a thing to do. Also that I have at least one old battery that is on last legs. At least having an old string to misuse as backup is very useful in getting the new two started correctly.

Freewilley · August 2017

So watching youtube videos about my Craftsman 400 clampmeter.
Testing the cables out of the inverter I find my reading is jumping from .93 to various readings up to 3...system is on absorb and there is little draw.
Am I doing something wrong?

BB. · August 2017

Is this an ac/DC current clamp meter?

Are you clamping on one cable at a time? For ac wiring with a cord, you have to split the cord into separate wires and clamp one at a time.

Using DC amp range on DC battery cable and ac on 120 vac output?

You can clip onto your car's battery cable and play with lights, engine stopped and running to get an idea how to make measurements.

For dc, you have to zero the meter before making current measurements. With no wire in clamp, first push zero button to no ZERO in lcd dispkay. Then press zero button one to zero reading. ZERO should be on in lcd now. Now clamp on one wire to measure dc current.

Bill

Horsefly · August 2017

You can buy small little devices that provide a split connection for using a clamp meter, like this one: https://www.amazon.com/Amprobe-ELS2A-AC-Line-Splitter/dp/B001DPR0FE

Freewilley · August 2017

Thanks Bill. I read the threads on the basics.
It is the Sears AC/DC 400
Now I need help analyzing...So the string was absorbing and the neg at the inverter read 1.59 to 2.35, bouncing up and down. Turned on EQ and was 7.7, up and down maybe 5%.

Is that expected results?

BB. · August 2017

Most DMMs "sample" the current (say once a second). When you have DC loads (and chargers) that switch on and off (PWM mode--Pulse Width Modulation) it is very possible to get less than stable readings (i.e., the meter sampling and the PWM cycling "alias" between each other).

Otherwise, I am a little confused here. Are you using the the AC inverter for charging your battery bank when making these measurements (clamping negative DC lead to inverter?).

In general, it is better to measure the positive lead for current flow. Most systems are negative ground and it is possible that you have parallel ground paths to the battery bank (although, for big DC stuff, the DC negative should be isolated from the DC ground green wire). So I do not think that is the issue here.

If you want to measure battery charging current--You really need to measure at the battery bank (clamp on Battery + wire to battery bus + common connection). Current is like "water flow", if you measure the current at some other point in the system, you will be having the mathematical addition and subtraction of current flow (i.e., +20 amps from solar charger -10 amps from AC inverter = +10 amps into the battery bank).

Note that DC Current Clamp meters will display + and - for current flow direction. However, you have to be aware of what direction you place the wire through the jaws. Flipping the wire through the jaws of the meter will change the polarity of the current flow (for the meter reading).

-Bill

Freewilley · August 2017

Still not sure what current I should expect, but at least now I know where to measure it...

I started an EQ on one string today, stopped it and then tried to force bulk on both the MX and FM. The MX is acting the way I have seen before, it goes to bulk but quickly reverts to bat full.
So the FM will stay on absorb but is missing 60% of the PV. But I have run absorb on both when I do not try to restart on Bulk
So I just went back to EQ on the old string,,,,they do not come up past 75% SOC unless I eq. I did try to run the absorb on them, after more than an hour they had not come up at all.

Overall I am happy to be able now to baby the new string and bring them quickly up to 100% SOC by changing the strings with my switch.

Starting off with 2 new Surettes, but cutting my bank in half to try and make this work this time

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