Another Mx60 Question?

backroad

I've been searching for a battery charge problem and ended up purchasing a MATE for more control of my VFX3524. I think OUTBACK could have either simplified the controls or at least did some better explainations for trouble shooting.

Anyhow, all this time, when i've been charging from my generator (which has been quite a bit), my MX60 has always shown B-MPPT in the lower right corner of the main screen. Now, after fiddling and resetting some things, it now says ABSORBING. It's never shown this before. Can anyone tell me the difference between B-MPPT & ABSORBING?

For the last year, I believe I've been undercharging my batteries greatly and my hydrometer readings have only come up to about 1.2, which is not good. Today, (of course after the fiddling thingee) it's comming up. It's now up to almost 1.25 and still "ABSORBING". Did I finally do something correct.

Dennis in Bagdad.......................................AZ..........

crewzer

Re: Another Mx60 Question?

Dennis,

… after fiddling and resetting some things, it now says ABSORBING. It's never shown this before. Can anyone tell me the difference between B-MPPT & ABSORBING?

B-MPPT means that the MX60 controller is operating in the Bulk (MPPT) mode. It’s attempting to supply enough current to raise the battery voltage to the absorption stage target.

Absorbing means that the batteries have reached their target absorption stage target, that the B-MPPT stage is complete, and the controller is limiting current to maintain target battery voltage.

Did I finally do something correct.

Yes. “Absorbing” for a couple of hours a day and several days per week (minimum) is a good thing!

Enjoy!
Jim / crewzer

System2

Re: Another Mx60 Question?

Others with more experience will add to this I'm sure, but here goes.

No, unfortunately, I don't believe you did finally do something right.
All indications from the info you have given, are that the MX-60 was trying to do it's job - - before you fiddled with it and reset some things.

Reason I say this, is that you tell us that your batteries were not coming up to full charge. The fact is that the MX-60 recognized that and was continuing to attempt a Bulk Charge (B MPPT) which stands for Bulk, Max Power Point Tracking.
ONLY when the batteries are nearing full charge, was the MX-60 originally programmed to start cutting back on charging current (if indeed that current is available) to properly control the final top up of the battery charge. This is the "Absorbing" stage. Finally, again assuming the power is available to finish toping up the batteries, the MX-60 will switch to "FLOAT", which is a lower "holding" voltage.
The fact that the MX-60 (before you "adjusted" it) never came out of B MPPT mode, PLUS the fact that your SG readings only show an undercharged state, indicate to me that (assuming everything is wired properly) the power source for charging, whether that be Hydro, Solar, or wind, is NOT supplying enough power to properly keep up with what you have been taking from the batteries, and, or properly charge the batteries.
Let us know what you have for batteries, what your loads are, what you have for a charging source, and we can give you some information on what's going on, AND what the proper settings should be for the MX-60.
Indications are that you adjusted down the voltage settings of the MX-60 so it "thinks" the batteries are ready for the final top up stage, when in reality they are far from it. It's like readjusting the speedometer on your car to show 60 miles an hour, because you wanted to go that fast, but the engine only had enough power to make the car go 30.
Sorry to have to say, but depending on how long the batteries have been kept in the undercharged state - - they may well be now ruined
We wait for more information from you.
All the best
Wayne

backroad

Re: Another Mx60 Question?

I've already figured that I have hurt the batteries, so now I'm going deeply back into the learning stage.

QUOTE: Let us know what you have for batteries, what your loads are, what you have for a charging source, and we can give you some information on what's going on, AND what the proper settings should be for the MX-60.

I have 12 of the L16 6v Crowns (395ah)
I never have really figured my loads as they change so.
About 1300 watts of panels.
Generator is a wheelhouse 8500 that puts out a
continuous 5500 watts.

The batteries have been in an undercharged state for about a year now.....:(:(:( and are only a year old. So sad. I now know that I shut my generator down way too soon, and Niel and Crewzer have told me that I did not have enough Panels for my batteries. I've now got 6 more 130 watt panels and a second MX60 to install after I get a couple of deep holes dug for the mount.

Now that I may have a slight clue on how the MX and MATE work, any help getting them programmed correctly would be just awesome. This truck driver just wasn't really meant for electrical stuff and the electrician son doesn't have enough time.

Thanx again,

Dennis in Bagdad......................................AZ........

System2

Re: Another Mx60 Question?

OK, from the inverter model number, I take it that you have a 24 volt system, so you would have 3 strings of 4 batteries. 3X395 amp hrs= 1185 AH X50%= 590 AH that you could draw down from your fully charged battery bank IF the batteries were in top condition. Unfortunately, I fear that's no longer the case.
For proper charging, it's standard to have available from your solar panels, between about 5% and 10% of total battery capacity, which would be between 60 and 120 amps, and up to 30.5 volts, to be able to run the EQ mode.
Your 1300 watts of PV, when all losses are included, will probably only give you 35 amps or less. Your 6 new panels would probably add almost another 20 amps, bringing the total available to perhaps 55 amps. Probably close enough - - - - ASSUMING that you aren't using so much power from the batteries that the panels just can't keep up!
I have basically the same batteries, but from Power Battery. Power Battery gave me the following specs for charging a 24 volt bank:

Absorb 28.8 - 29.4 Volts at 25*C BATTERY Temperature
Float 27.6 - 28.2 Volts at 25*C BATTERY Temperature
Equalize 30.0 - 30.6 Volts at 25*C BATTERY Temperature

Those are the voltage settings your MX-60 should be set for, to properly look after your battery bank. AND NOTE, that these voltages only hold for a BATTERY temp of 25C. That's where the remote battery temp sensor comes in. It feeds the battery temp info to the MX-60, which them automatically adjust those voltages up or down as required, to match the battery temp.
The MX-60 should be set to do an EQ about once a month, for 3 hours max. BUT, it will NEVER successfully complete an EQ, UNTIL the batteries have reached a full charge FIRST.
Your next step is to get the new panels up and running, and you must get a handle on your power consumption, otherwise you will never know where you stand.
If I sounded grumpy, that was not my intention, I just needed to get the thoughts across clearly.
I wish you the very best of luck and that you can salvage your batteries. Is there any way that you can shut all loads off for a day or so, once you have the MX-60 properly programmed, so you can get a damned good charge in those batteries and do an EQ? In fact, it may take more time, depending on how low they are and how much sun you get etc. If your loads are sucking up everything from the PV's, there will be nothing left to charge the batteries, which I suspect has been the case all along.
Good luck
Wayne

System2

Re: Another Mx60 Question?

Just had another thought - -
What is the voltage coming in to the MX-60, FROM your panels?
The system would do best if the panels were wired to provide the MX-60 with about 48 volts more or less. The MX-60 will automatically adjust from there, to provide what the batteries need, as long as the panels can provide.

backroad

Re: Another Mx60 Question?

You did not come across as "grumpy"...

The voltage comming from the panels to the MX IS 48 volts.

As for shuting everything down for a day or two.....well, that would mean running the house completely of of a generator. Could happen.........

My current setting for absorb, float and eq are just a couple of tenth's higher than your suggestion.

My daytime Pv charging is not too awefull bad, as I gain quite a bit on the batteries. I just have to run the gen a couple of hours in the evening and they are down pretty low in the morning. Usually 24.3 - 24.6 and occasionally a bit lower.


My largest draw is my frig...and it's not bad at 1.1 - 1.2kw day. We run a couple of 13 watt CFL's, some computer and a bunch of TV. The wifes 32' uses about 48 watts and the 36" uses about 85 watts. Everything that can be on a power strip IS and is shut off when not in use. The Direct TV receivers draw 8 watts and 7 watts on standby. We heat the house by gas and woodstove, using NO electricity. Generally, I believe we're in pretty good shape there.

I know this is an ongoing learning curve and nothing happens suddenly. I just hope I can make my year old battery bank survive another couple of years.

System2

Re: Another Mx60 Question?

Sounds like you're very close on most things, to where they should be, except for the total loads and the need to get those new PV's installed.
I'm assuming you have an upright, regular fridge.
Have you considered a chest fridge? I converted a chest freezer to a chest fridge, and it uses about 1/3 KWH per day. I'm VERY pleased with it's operation. But then I don't have a wife to blast me. LOL What power you don't use, you don't have to produce.
Well, it's 2:30 AM here and way past when I should be asleep so I'll say Good Night and good luck.
Wayne

System2

Re: Another Mx60 Question?

Just going over this thread and taking in the info that your MX-60 voltage settings are within a couple of tenths of what Power Battery told me for the same batteries.
I would strongly suggest that you contact the manufacturer of your batteries and find out EXACTLY what voltages they recommend. Reason is, that being off by "a couple of tenths" in the voltage settings can, over time, make a big difference in battery operation and life.
It will be interesting to see if and what any differences between the two manufacturers will be for the same model battery.
All the best.
Wayne

icarus

Re: Another Mx60 Question?

I agree with Wayne about the fridge. 1.0=1.5 kwh/day is not too bad with a grid tied system, but it clearly a big draw on your system. (I don't think a new 'energy star" rated fridge will do much better). You might look to Wayne's suggestion, or think about propane. Propane comes at a cost, both to purchase as well as the fuel, but it can make a PV system MUCH smaller to fill all your other needs.

You could also look to see if you are using your fridge efficiently. Keeping it full is way more efficient that partly full. (I even fill jugs of water to keep the mass in the fridge when it is less than full). Also keeping good air circulation inside and outside the cabinet. A simple, cheap add on to dramatically lower the energy use of a fridge is too add insulation to the outside of the cabinet. If your cabinet has coils back or under, a simple layer of bubble wrap on the cabinet, or 1-4 of foam board will cut the cold loss by a lot. It sounds like your climate is hot, (AZ) so keeping the temp difference from the outside to the inside as small as possible. Barring that, more insulation.

Good luck,

Icarus

backroad

Re: Another Mx60 Question?

My 1.1 kwh is an Energy Star Sears and If I were to cover it with any kind of insulation, It would probably end up almost like me trying to use a chest type freezer that was converted to a frige. :):):( Momma would come apart.

Since I'm probably going to have to replace my battery bank sometime in the forseeable future, anyone got any ideas as to the next step upgrade. AGM's would really be nice, but expensive and would probably take quite a few of them to match (or better) my current 12 L16's.

System2

Re: Another Mx60 Question?

NO, I would not, in your circumstances even consider AGM, or anything but flooded. Reason being, the L-16 flooded batteries can take a ton of abuse compared to AGM's, and it looks like your rather new L-16's are already failing due to improper charging etc. AGM and Gel will not take any abuse at all and last. By comparison, the L-16's are very forgiving. But even they have their limits, as you are finding out.
Good luck with whatever you decide.
Wayne

nigtomdaw

Re: Another Mx60 Question?

As a suggestion why dont you try using your generator in the morning to bring your batteries up to bulk to absorb switching voltage (approx 28.8v) timing it to complete this task about an hour before solar noon then allow the solar to provide either A a full absorb charge, or an monthly equalising charge.

If you can do this absorb period 3 times a week for a couple of weeks you might bring your batteries up and its about the most efficient way fuel usuage wise.
(edit, good practice says not just for 3 weeks,every week when your solar is not providing at least 3 absorbtion charges weekly)

You can then be sure that the MX 60 can fully charge your batteries with that all important absorption 2/3 hour charge.

Remember when you change from Bulk charge to absorbtion charge your wet LA batteries are aproximately 80% charged, that all important absorbtion period adds that final 20% before tripping in to the third stage, float which basically maintains the status quo by putting in whats been taken out, from your loads.

You should see an improvement on your status voltage the following mornings because you have effectively regained that lost 20% of capacity by doing this.

HTH. Works for me and others here in Spain .

System2

Re: Another Mx60 Question?

For the record, I agree 100% with the above suggestions from "nigtomdaw"!
Wayne

OH, and the 28.8 volts mentioned, is for a battery temp of 25 degres C.
Add about .03 volts for every degree C, that the actual battery temperature is BELOW 25C and subtract the same for every deg. C above 77C.
If you were strictly charging off Solar, your MX-60 would do that automatically, as long as the Remote Battery Temperature Sensor was properly installed.

backroad

Re: Another Mx60 Question?

How do you not install the battery temp sensor correctly?:D

Windsun

Re: Another Mx60 Question?

Wayne from NS Cana wrote: »

NO, I would not, in your circumstances even consider AGM, or anything but flooded. Reason being, the L-16 flooded batteries can take a ton of abuse compared to AGM's.... .... AGM and Gel will not take any abuse at all and last.Wayne

That simply is not true. While gelled are easy to abuse, any true deep cycle AGM can take as much or more abuse than a flooded.

System2

Re: Another Mx60 Question?

Windsun wrote: »

That simply is not true. While gelled are easy to abuse, any true deep cycle AGM can take as much or more abuse than a flooded.

==============================================
Thanks for straightening me out on that. That's what I love about this form, it's a real learning experience for so many of us
Wayne

Just remembered, where that idea of mine had come from. When I bought my L-16's over 5 years ago now, I was working for a major Canadian retailer, and looked after our local battery purchases from Power Battery. When I spoke with the P.B. rep about my wanting batteries for solar, I mentioned that I was considering going with AGM. He practically refused to sell them to me for the reason I gave above. Now I wonder - - were the Power Battery AGM's just no good at that time, or did they just want to move out an overstock of Flooded, or was he just mis-informed.
Very interesting.

Ralph Day

Re: Another Mx60 Question?

Backroad,
You can not install the temp sensor correctly by: plugging it into the Mate connection instead of the Temp sensor hole (in your MX60). I spent the first 2 years off-grid this way. No damage, but no temp comp either.

Once rectified (put plug in correct hole) i realized the OB temp comp was very different from the Xantrex. While the initial actual to comp voltage for both units will read .8vdc, once you start charging (genset charge) the X will read the same for actual and comp-ed usually within 45minutes, the OB might take several hours. One sensor must be more sensetive than the other. So when i charge with genset, i sometimes observe where the MX temp comp voltage is targeted and adjust the Xantrex to match it. I have too much time on my hands.

ralph

ps i'd also say don't give up on your current batteries yet. Do some major desulfating eq charges as per Surrette/Rolls bulletins.

Windsun

Re: Another Mx60 Question?

Wayne from NS Cana wrote: »

==============================================

Just remembered, where that idea of mine had come from. When I bought my L-16's over 5 years ago now, I was working for a major Canadian retailer, and looked after our local battery purchases from Power Battery. When I spoke with the P.B. rep about my wanting batteries for solar, I mentioned that I was considering going with AGM. He practically refused to sell them to me for the reason I gave above. Now I wonder - - were the Power Battery AGM's just no good at that time, or did they just want to move out an overstock of Flooded, or was he just mis-informed.
Very interesting.

Well, I should revise my statement a bit. Major brand AGM deep cycle batteries, like Concorde, Deka, Trojan, can take a lot of abuse. However, in the AGM world there are a lot of cheap knockoffs and non-deep cycle types that are really only good for starting batteries.

System2

Re: Another Mx60 Question?

Good info as always Windsun.
Thanks for that.
Cheers
Wayne

backroad

Re: Another Mx60 Question?

Maybe I have installed the battery temp sensor incorrectly. It's not plugged into the mate or the Mx60, but it IS plugged into the inverter. I believe that's where the instructions said to, though.

I am currently running the generator a while in the evenings, because we watch way too much TV, and of course my wife and I don't usually care for the same channels. Running two TV's, oops. I'm also trying to use the generator in the morning to ease up on my inadequate solar. I really need to get my diesel generator back together, up and running.

I going to get off here now, call Hardy Solar and order my Changfa parts. BTW, you are all really full of it....good information that is.

mike95490

Re: Another Mx60 Question?

backroad wrote: »

Maybe I have installed the battery temp sensor incorrectly. .... but it IS plugged into the inverter.

Ouch ! That does not sound good.

EDIT:
Not having any Outback gear, I don't know what is supposed to plug into where. AFIK, inverters only care when they themselves get too hot. I did not know the inverter ALSO had a charger in it.

crewzer

Re: Another Mx60 Question?

Plugging the RTS into the inverter enables the inverter battery charger’s temp comp function. If the same inverter is plugged into port #1 of an OutBack Hub, then battery temp data will be shared with other inverters and/or controllers also plugged into the Hub.

If you’re not using a Hub, then the simple (and cheap) thing to do is to order another OutBack RTS and plug it into the MX60’s RTS jack.

HTH,
Jim / crewzer

backroad

Re: Another Mx60 Question?

The second BTS sounds like a good idea. I'm sitting on a second MX60 until I can get up my 6 new panels. Would this mean that I should get a third BTS.:):):)

With multiple MX's, would it be a good thing to think about a HUB? I'm still only going to use a single inverter. Or is there any advantage to the HUB in my situation?

niel

Re: Another Mx60 Question?

maybe you should get the hub.

crewzer

Re: Another Mx60 Question?

Dennis,

Buying a Hub ($156 street for a 4-port mode, $300 for the 10-port version) is probably overkill if you’re just looking to share battery temp data from a single RTS to an inverter an a couple of MX60 charge controllers. Another couple of RTS’ ($26 each) should suffice.

However, if you want to use the Mate to remotely monitor the inverter and controllers, and to perhaps someday add a FlexNet-DC system monitor and/or another inverter, then a Hub would be required. The -10 would probably be the better choice, as a single inverter and a pair of controllers plugged into a -4 would leave but one spare port (The Mate plugs into its own specific jack and is not part of the device count).

HTH,
Jim / crewzer

rrbv

Re: Another Mx60 Question?

Something wierd here. I have a 1.2kw solar array, with two L16 packs at 24 volts. I have a refrigerator that runs about the same, 1.1 kwh/day, have a directtv system and one lcd tv, plus many cf lights, computer, etc. My system is always in float by 10 or 11 am.
The trimetric shows typically 90% in the morning before the sun comes up, ocasionally 85%. I can equalize any day the sun shines, and have no backup generator. I have a Blue Sky 50 amp MPP charge controller and a Trace 4024 inverter.

Something doesn't make sense. I live in NM where there is a lot of sun!

rrbv

BB.

Re: Another Mx60 Question?

Using this link and the City as El Paso Tx (seems to be closest to where you live?) and 1.2 kW of solar panels...

For February, you get roughly:

148 kWhr/Month / 30 days = 4.9 kWhrs per day February average...

Assume that your batteries are flooded cell at 80% efficiency and your inverter is 85% efficient, you should get:

4.9 kWhrs/Day * .80 * .85 = 3.35 kWhrs per day of useful work...

You add up all of your usages and see how that works out for you...

1.1 kWhr Fridge + 0.4 kWhrs / 8 hours laptop + 0.6 kWhrs for TV+lights? = 2.1 kWhrs per day... Seems to be pretty possible.

-Bill

System2

Re: Another Mx60 Question?

I have freezer, "chest fridge", lights and everything but water pump (so far) on 1000 watts PV with 3 packs of L-16 @ 12 volts and when we have sunny days, I'm also seeing float, often before noon. Reflection off the snow helps too
Yesterday,before 10 AM, just seconds before it hit Absorb, the MX-60 was showing 59.4 A / 930 watts / 15.3 volts. (batteries are cold in outside shed, but inside insulated box which is a huge help)
Once Absorb is hit, the power output is all downhill from there on throughout the rest of the awesome sunny day. What a waste
Oh, and that was with the freezer in continuous run mode, which is where I set it on sunny days. Of course I put the freezer back to normal setting just before the sun goes down.
All in all, sounds much in line with your experience. I'm happy with it
Wayne

backroad

Re: Another Mx60 Question?

Wayne......Looks like you are charging 6 batteries from 1,000 watts of panel? Are you also powering a refrigerator, computer and TV(s).

What I understand from the "wiser others" is that I do not currently have enough panels for my batteries....YET... I can actually survive a number of days on the output of my current panels and batteries if I have sun. Most of the time we have at least one TV on, a computer quite a bit, Frig, aquarium (with heater, lights and pump) and at night a couple of CFL's. I've got a pretty good feeling that I'll be fine (even if I plug the Chest freezer in) after I get up the other 6 panels (another 75 watts)......

crewzer

Re: Another Mx60 Question?

What I understand from the "wiser others" is that I do not currently have enough panels for my batteries…

Dennis,

Just to clarify: My recollection is that you don't have "enough panels" for your loads. That's different from "not enough panels for your batteries".


The PV array needs to be sized to environmental conditions and loads as well as to the battery bank size. From a snapshot perspective, Wayne’s charging a 12 V battery bank rated at somewhere between 950 Ah and 1200 Ah from an array rated at 1,000W STC. The PV array is a good match for the battery bank (~1 W per Ah at 12 V), and he also seems to have balanced his loads (Wh/day) against his local environmental conditions (hours of “full” Sun and other local factors).


HTH, Jim / crewzer