[johnkmaloney]

Hello,
I recently replaced my old set of batteries with new ones. The batteries reached the end of their life a few years ago and I have had the car sitting in the garage since then. I had ten Deka 12v 105Ah 8A31DT batteries and I replaced them with exact same thing (the new batteries are called 8A31DTM but they are still Deka AGM 105Ah batteries).

I connected the new batteries and the car drives fine and I have all the voltage coming out that I expected. The problem is when I tried to charge the car. I have an Elcon PFC 2500 charger that worked fine before but now it is giving me an error.

When I plug in the charger, it flashes Red-Green-(five second gap) and repeats. The manual shows that this is the error code for "wrong battery". I tried unhooking the charger and plugging it in and it correctly gives my the code for "no battery".

I'm not sure what's happening here since the charger worked fine before and I just put the same kind of batteries. Any ideas?

Thanks,
John

 

[john61ct]

I believe it can only be a voltage issue.

Too low more likely than too high.

 

[johnkmaloney]

The batteries were all at 12.75 volts when I put them in and the total voltage for the pack comes in at 127.5 for the ten batteries.

 

[john61ct]

And how does that compare to the previous set?

Maybe something got shorted during the swap?

Try contacting Elcon support?

 

[johnkmaloney]

The voltage is the same as my old set. Before, if I plugged it in with ~127 volts showing, the charger would blink red (<80% charging) or yellow (>80% charging) and eventually go to green (full charge) at around 130 volts.

I only swapped the batteries out and I tried plugging in the charger a few different times in case it needed to reset itself. Everything else on the car is working fine so I think the fault is with the charger. I checked the connections and everything looks good.

I emailed Elcon but I had tried getting customer support from them in the past and it was hit or miss.

If the Elcon charger doesn't get working, I will probably go with a different brand. Has anyone had luck with the Quick Charge brand?

 

[kennybobby]

Do you know what switch setting you were using before versus which setting it is on now? Usually there are 10 settings of the little push button switch on the control board which are used to select different sized batteries, e.g. total number of cells to be charged.

There is a procedure to check the setting and make changes to adjust it, hopefully it is in your manual, but if not look in the TCCH/Elcon troubleshooting and repair thread for details.

i wouldn't expect it to change settings on its own, so maybe there is a problem with the divider circuit that reads the voltage.

 

[johnkmaloney]

I've never changed any settings on the charger. It was programmed for my batteries so that's why I bought the same exact kind so I wouldn't have to change anything with the charger.

I looked through the troubleshooting thread but I couldn't find anyone with the same failure as me. I'm hoping I don't have to take the charger apart to find the fault.

When I unhooked the DC leads of the charger, it did give me the "no battery" error so I think it must be "seeing" the batteries when I have it hooked up.

Is there a way to check what settings the charger has to verify it's still on "factory" conditions? I've been reading about a button to change the settings under a sticker but I don't see anything like that on mine.

I really appreciate the help, by the way.

 

[kennybobby]

i think the instructions are on page 3 of the elcon pfc2500 manual. There is a tiny red LED on the board near the pushbutton which i thought was used to blink a number to indicate the curve, but the manual makes it seem to be the Red Green Yellow LED that blinks the curve setting number, so i'm confused...maybe someone else can chime in with the answer.

Here is a picture from page 4 showing the pushbutton access ports where i have marked it for clarification. At least you can check/count to see which curve you have.

Then you will need Elcon to send you the table of curve settings for your charger to know if it is the correct one.

 

[john61ct]

Yes, may have changed even if you didn't change it

 

[Coulomb]

Yes, may have changed even if you didn't change it

It seems unlikely, as the setting is stored in flash memory, much the same as the firmware program is. But it's possible, so do try it.

It is the main red/green LED that counts the "user program", not the tiny red LED under the sticker.

Often, the table of user settings (if any) is printed on a sticker attached to the charger somewhere, like the third photo in this post.

 

[johnkmaloney]

Thanks for the info. I removed the charger from the car and found the button underneath the sticker. I plugged in the charger and counted the four red flashes meaning I should be on curve 4. The sticker on the side has "Default curve: 4" so I think that should be okay.

I will try again to connect the charger and see if it still does curve 4 followed by the wrong battery error. If it still doesn't work, I guess I'm going charger shopping.

Thanks again for the help.

 

[john61ct]

Do you have the specs for curve 4?

Is that what it was set to before?

 

[kennybobby]

Here's an idea:
Can you try to adjust the battery voltage, either up or down, in 2 volt increments, and try charging again? The charger curve is programmed with a voltage per cell for the type of battery, and then the number of cells. Multiply these two values and it gives the expected pack voltage.

There is a circuit to measure the pack voltage and if it is not within the expected range, it throws the error.

The problem could be with the memory values stored in the program (not likely), or in the measuring circuit (degraded resistor values in a voltage divider).

This one sounds like a good candidate for repairs if you are interested.

 

[john61ct]

How does one "adjust battery voltage"?

 

[Coulomb]

[ Edit: I see that Kenny had the opposite idea (adjust the actual battery voltage, not the battery-side charger set-point voltage). But one way might be more convenient than the other, so I'll leave my suggestion here. ]

How does one "adjust battery voltage"?

Choose curve 5 to (presumably) go up in voltage, and curve 3 to (presumably) go down in voltage. It's presumed that these voltage changes will be one cell's worth, or 2 V nominal (for lead acid).

You adjust the "curve" by pressing the button while the charger is off, turn it on, and release it after the appropriate number of flashes has occured (more complete details in the manual, which can be found online). If you get the the wrong number, just try it again. You don't need a battery connected for this.

Perhaps use something plastic to press the small button under the label, so there is no chance of shorting anything if you slip off the button, and you won't get any kind of shock that way.

This idea of Kenny's is a good one, and could result in by far the least cost and hassle to get you going again.

 

[kennybobby]

Use the pushbutton to change the charger setting, or

physically change the battery voltage.

Add or remove "cells" from the pack voltage.

Discharge 2 volts to remove a cell, or charge 2 volts to add a cell (add charge to individual 12V Deka modules as necessary to effect a 2-volt total distributed increment)

Obviously the pushbutton is easier to try than messing with actual pack voltage, so there is no harm in trying all the settings if necessary to see if any of them will work.

 

[john61ct]

Choose curve 5 to (presumably) go up in voltage, and curve 3 to (presumably) go down in voltage.

That is changing the charger voltage, not the battery's.

If we were working with 2V cell units and putting them in series to get to our pack voltage

a much better idea than 12V packaged units in the first place for those few still working with lead EVs

then this idea would be more workable.

But bringing a 12V unit down by 2V is pretty damaging to the cell, 10.5V is zero SoC by definition.

4V way way too low.

Worth playing with a cheap worn battery I suppose, not a good idea for those actually in production use.

 

[john61ct]

And the point is, OP needs the charger to work at a specific curve choice (preset voltage setting), not going to change the bank voltage to match another curve selection.

 

[Coulomb]

But bringing a 12V unit down by 2V is pretty damaging to the cell, 10.5V is zero SoC by definition.

Sure, but we're talking 2 V over the whole pack. So you could use headlights or the heater to lower the whole pack voltage. Or just drive up to the shops to buy some milk.


I can understand not wanting to do that when the charger isn't working. That's why adjusting the charger output voltage (and therefore also the expected battery voltage) may be more convenient. I'm not suggesting you leave it there, but you could check that the charger will actually charge that way. Then use a multimeter to check what voltage it actually charges to.

 

[john61ct]

As I said with a cheap sacrificial battery maybe, not a production bank, just too risky would cause permanent damage, certainly shorten lifespan.

To do a strictly controlled load test less risky but only with all the other infrastructure working fine.