Problems getting the new Schneider/Xantrex C-35 controller to work...

softdown · July 2017

Last week, the LED started flashing red and green. That means that equalization is enabled. Equalization is supposed to stop after two hours. If it fails to do so, one is supposed to be able to use the "reset" button to correct this.

I didn't change any setting before it started flashing red and green. Pressing the reset button multiple times did nothing.

Busy fixing a boat bottom so I hooked up the large freezer to the 48 volt main solar system until I could address this problem with the 24 volt system.

The main system failed at 1am this morning. One of the eight 12 volt batteries has two bad cells. I am going to see how I do with four 8Ds now. The main 48 volt system is now a problem for a different thread.

It would seem that solar systems require an ever vigilant eye.

littleharbor2 · July 2017

softdown said:

I didn't change any setting before it started flashing red and green. Pressing the reset button multiple times did nothing.

Manual says to stop equalization press the reset button until the led goes out. I take that to mean press and hold the button. Is that what you are doing?

softdown · July 2017

littleharbor2 said:

softdown said:

I didn't change any setting before it started flashing red and green. Pressing the reset button multiple times did nothing.

Manual says to stop equalization press the reset button until the led goes out. I take that to mean press and hold the button. Is that what you are doing?

I never took the steps to enable equalization and the readings never indicated that equalization was happening. Yes...I tried pressing and holding. I will try again....for ten seconds this time. Though I am pretty sure the CC simply went "maverick".

softdown · July 2017

So.......the LED turned off after eight seconds. After about two seconds it started flashing green again.

To be honest, I have been concentrating on rehabbing a boat bottom and have largely ignored my solar arrays. Finding myself wondering about battery damage now.

How and why did the CC slip into equalization mode and stay there? I'd say the CC read EQ mode for about ten days. Like I said, wasn't paying enough attention to it.

littleharbor2 · July 2017

How long has this controller been in service? Are you sure the equalize function is disabled/set to manual?

softdown · July 2017

littleharbor2 said:

Haw long has this controller been in service? Are you sure the equalize function is disabled/set to manual?

It has been in service for a few months. The equalize function was indeed set to automatic. I never seen it flashing red/green until recently. It is supposed to automatically quit equalizing after two hours.

Solray · July 2017

You may have damaged the internal timer circuit. Maybe when it was connected to the array without the battery connected first?

Has the timer worked right every time before this time?

softdown · July 2017

Solray said:

You may have damaged the internal timer circuit. Maybe when it was connected to the array without the battery connected first?

Has the timer worked right every time before this time?

I may have done that. Wondering why it took so long to start equalizing. I would also bet that few people, outside of working pros, know the batteries must be hooked up first.

You offered a good explanation at the least.

If hooking up the batteries first is urgent, manufacturers ought to make this requirement very clear. Only a small percentage are going to closely examine gigantic, generally pontiferous, installation manuals.

In fact, I think instincts would often lean towards hooking up the batteries last. One generally "plugs in" a device to power after everything is ready to go.

westbranch · July 2017

Softdown, you are right about the connections of all components should be done first, but the critical point in the process is after hook up, you have to POWER UP the CC, before opening the connection to the PVs (throwing the circuit breaker?)
AFAIK, all the CC manufacturers have it in their manuals... hth

littleharbor2 · July 2017

Those Trace/ XantrexSchnider controllers are pretty tough. I doubt it's damaged. Sounds like you haven't seen it in equalize mode before. Sounds like it's working properly now.

Solray · July 2017

softdown said:

Solray said:

You may have damaged the internal timer circuit. Maybe when it was connected to the array without the battery connected first?

Has the timer worked right every time before this time?

I may have done that. Wondering why it took so long to start equalizing. I would also bet that few people, outside of working pros, know the batteries must be hooked up first.

You offered a good explanation at the least.

If hooking up the batteries first is urgent, manufacturers ought to make this requirement very clear. Only a small percentage are going to closely examine gigantic, generally pontiferous, installation manuals.

In fact, I think instincts would often lean towards hooking up the batteries last. One generally "plugs in" a device to power after everything is ready to go.

Probably true. I read every manual 2 times before starting any project, but that's just the way Dad taught me when we were building models as a kid. He was a Cadastral Engineer and a(n) RLS.
A small sticker on the inputs and outputs of the controller would save a lot of damaged equipment over the years, but then it would also hinder sales of replacement products damaged by customer error and they are in business to sell things after all, it just seems a little devious.

While perfectly sound, the trouble with the 'connect to power after all other connections are made' concept fails when a system (like a charge controller in a solar power plant) has multiple possible sources of power. Batteries and panels can both provide power so it is not intuitive which goes first. Working on a car, it's obvious that you connect the battery after all your electrical connections have been made so anyone with an automotive background will lean that way.

softdown · July 2017

I came across an Air Force employee evaluation form for my late father. I believe it was filled out in the early sixties though it could be late fifties....going from memory.

One of the questions was real close to this: "Does employee have to read instruction manuals prior to assembly?" Back then, we were highly encouraged to "figure things out". Reading between the lines, only stupid people needed the directions.

That has changed of course but many dinosaurs are left with the old "figure things out" mentality.

He was a medical electrician by the way.

softdown · July 2017

It appears that days of equalizing has done severe battery damage. At 3:15pm, I read only 24.6 volts. A very low reading for this time of day. It would be acceptable at 7am. So goes the business of life at times.

It is possible, of course, that it will take a few days to charge back up. Last night it was charged with servicing, for ~seven hours, two freezers and a fridge due to the loss of the main 48 volt system.

As for me, I am operating with an ~ 50% SOC due to last nights drama. I'm sure some of you think that is very generous based on today's posting....

littleharbor2 · July 2017

Are you sure this controller has been equalizing for days? Have you seen the, Red/Green lights on for days? If you were equalizing for days your batteries should be very low on electrolyte and the voltage should have been quite high, at least when you shut down the event. What was the electrolyte level?

Estragon · July 2017

Assuming they're flooded, you may want to check water levels. EQ is hard on them, but if they didn't overheat (temp comp'd?) the main risk is exposed plates.

softdown · July 2017

1650 pound forklift battery being charged by 360 watts of panels. No....equalizing is not the problem. The cells are still full from mid-May filling and using water miser caps.

Something is quite wrong, I just need to find out what it is. The S.G. readings correspond to the low voltage readings. This battery should be highly charged. It had no load for about a week.

It is almost as if the charge controller was doing nothing while blinking red and green. Tomorrow may yield more findings. Interesting that my old and ill cell phone died last night with the power outage. It will not turn on in spite of the usual tricks.

No attention at all to the solar systems has been exacting a price.

BB. · July 2017

The old Cxx series controllers do fail... And leaving the owner confused (blinking/nonsense LEDs) and with a dead battery bank seems to be common.

If your voltage and current measurements do not make sense for the PWM controller (i.e., the controller is not behaving properly), it is probably time to replace it.

-Bill

softdown · July 2017

BB. said:

The old Cxx series controllers do fail... And leaving the owner confused (blinking/nonsense LEDs) and with a dead battery bank seems to be common.

If your voltage and current measurements do not make sense for the PWM controller (i.e., the controller is not behaving properly), it is probably time to replace it.

-Bill

It is cloudy so trying to measure incoming and outgoing voltage will wait for the sun. If your allegation proves correct, this controller likely had a very short service life. Though with two controllers in the area, I'm not sure which was "new" and which was "abused". Had problems, likely with my panel wiring, which has reflected in the controllers. Hence....this meandering thread.

Sometimes, though rarely, there is more than one culprit.

littleharbor2 · July 2017

That is a big battery to try to charge with 360 watts @ 24 volts. You're only getting about 10 amps @ 24 volts, if that. Very poor charging to battery ratio.

Estragon · July 2017

With good water levels, and SGs matching voltage, the doing nothing but blinkinlights theory sounds right.

My phone needs to be at a minimal SOC to turn on (~10%).

softdown · July 2017

littleharbor2 said:

That is a big battery to try to charge with 360 watts @ 24 volts. You're only getting about 10 amps @ 24 volts, if that. Very poor charging to battery ratio.

The thing is macgivored, see signature, there are ~600 watts on another bank with battery jumper cables allowing current to flow. The whole thing is kind of an experiment with batteries bought at roughly scrap value. The forklift battery was advertised as a 48 volt....I made lemonades with it.

All it powers is a new energy efficient chest freezer in a cool location. Well....today it is powering two chest freezers due to trauma with main 48 volt system. Bad day for clouds...so clouds are representing. Been a rough day...a very rough day.

Estragon · July 2017

It happens to us all. Have an adult beverage and consider there are much worse things that could happen than a controller that fails before its time. Tomorrow's a new day.

softdown · July 2017

Estragon said:

It happens to us all. Have an adult beverage and consider there are much worse things that could happen than a controller that fails before its time. Tomorrow's a new day.

Things that have failed since 1am:
*Main 48 volt solar system
*Diesel genset failed to replace the main power like it always has in the past. Hooking up the genset normally induces higher RPMs as the genset charges the low battery bank. The genset did not respond to being hooked up to the inverter at all. RPMs remained low and I seen a voltage dip to 95 volts while at low RPMs....yikes. Hopeful this was caused by the battery with two bad cells but skeptical.
*Removed one 48 volt battery bank and hoping that the remaining bank is enough.
*Lost/misplaced/was stolen $300 gallon of Petit Trinidad boat bottom paint.
*Cell phone will not turn on in spite of battery swaps.
*Belly is still sticking out in spite of diet.
*Mystery blood on porch with no injuries to dogs or goats....found this yesterday. Appears that something was bleeding badly.
*Light in west wing quit working.
*24 volt bank is behaving strangely....current subject.

Think I'd smoke if I had anything right now.

softdown · July 2017

Apparently I have used 2.9KwH in the past 24 hours. Batteries at 55.1 volts at 5:20pm. Sure hope they don't collapse again in the middle of the night. I need some sleep.

Estragon · July 2017

I sincerely hope today is a better one for you.

softdown · July 2017

Have two solar challenges at the moment. Recent developments:
Xantrex C-35 shows about 27.6 volts at the terminals. That may seem alright though it is , of course, having little impact on the 1650 pound battery. The battery voltage has risen from 24.1 to 24.2 volts in the past two hours. Maybe the controller is OK now while it was doing nothing while blinking red/green.

48 volt bank survived the night with one battery bank instead of two. Morning voltage was 48.2. Still thinking of using it until it dies. Every month I squeeze out of it saves me ~~$75 in battery usage. Cripes....I could likely squeeze another year out of it by spending ~$400-600 on replacement batteries. Gee.

Genset usage is OK. I just managed it improperly when I awoke, stunned, to a 1am power outage.

Things are looking up today for sure. Yesterday morning was a nightmare. The controller was saying scary things like Comm Error etc. I was worried about a bad controller and/or inverter and/or genset. It was me being stupid.....out of practice.

BB. · July 2017

The PV input terminals on the Cxx should be about Vbatt output voltage or a bit higher (voltage drop across controller of ~1 volt or so?).

The output voltage, if 27.6 volts at the controller Vbatt output terminals and 24.1 volts at the battery bus--That is a problem and either is too small of current (correct typo) to battery wire diameter, and/or loose/dirty connections/corroded wire/connections. You should have around 0.1 to 0.2 volts maximum voltage drop from controller to battery bank (under full charging current).

-Bill

Estragon · July 2017

Flipped breaker while troubleshooting?

softdown · July 2017

BB. said:

The PV input terminals on the Cxx should be about Vbatt output voltage or a bit higher (voltage drop across controller of ~1 volt or so?).

The output voltage, if 27.6 volts at the controller Vbatt output terminals and 24.1 volts at the battery bus--That is a problem and either is too small of controller to battery wire diameter, and/or loose/dirty connections/corroded wire/connections. You should have around 0.1 to 0.2 volts maximum voltage drop from controller to battery bank (under full charging current).

-Bill

Yes....this is surely correct. I'll see what happened pretty soon. Thanks.

softdown · July 2017

BB. said:

The PV input terminals on the Cxx should be about Vbatt output voltage or a bit higher (voltage drop across controller of ~1 volt or so?).

The output voltage, if 27.6 volts at the controller Vbatt output terminals and 24.1 volts at the battery bus--That is a problem and either is too small of controller to battery wire diameter, and/or loose/dirty connections/corroded wire/connections. You should have around 0.1 to 0.2 volts maximum voltage drop from controller to battery bank (under full charging current).

-Bill

There was some corrosion so I cleaned up both bolted down connections. The controller showed solid green. Held down reset and it blinked red/green. Held down reset and it blinks green like it should.

Cloudy day....showing ~26.4 volts at controllers for panels and battery. Yet battery continues to read ~24 volts.

Is this possible? The bolt head for the neg is making contact with the bolt head for the grounding cable. Is that possibly the problem?

I think I found something more frustrating than custom aquarium maintenance.

Problems getting the new Schneider/Xantrex C-35 controller to work...

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