DPI Accusense 48v

[jbrzezinski14]

DPI Accusense came in yesterday. Unboxed her this morning, changed the settings to US Battery, plugged her into my 2010 RXV with six 8VGC US Battery batteries. It did it's check, detected the pack, and started charging (Red power LED is on, and one yellow charging LED). The pack was "fully charged" by the OEM Powerwise QE charger before I plugged the DPI in.

It's been gassing since shortly after it was plugged in, which made sense to me since the batteries were pretty much fully charged. That was about 5 hours ago. It's still gassing, still only has the one yellow LED lit, and has settled at 61.7v for the last few hours. The Powerwise would get the pack up to around 63v before shutting off. I feel like it should have charged for a much shorter period of time, then floated these suckers until needed.

Is this normal?

[JMGreco]

What you described is how my pack charges with the same charger and same batteries. My guess is that the old Power Wise charger was not capable of charging the US Batteries to the proper specifications and the new DPI charger is doing what it is suppossed to do.

[jbrzezinski14]

That's exactly what I was thinking, but I just wanted to make sure. I saw much shorter range with the battery setup I have than expected while using the Powerwise. One thing is for sure, this charger is pumping a lot more energy into those batteries than the old charger did...I'm guessing "fully charged" to this charger vs the Powerwise are two different stories all together...

[jbrzezinski14]

Originally Posted by JMGreco

What you described is how my pack charges with the same charger and same batteries. My guess is that the old Power Wise charger was not capable of charging the US Batteries to the proper specifications and the new DPI charger is doing what it is suppossed to do.

Do your batteries go through water quicker with this charger? How often do you top them off?

[JMGreco]

My batteries are a week old today, I am going to check the water levels this weekend. From the great advice I always get on this forum, I do expect the water levels to fall faster with the DPI US Battery setting than with my old powerwise charger.

[jbrzezinski14]

Originally Posted by JMGreco

My batteries are a week old today, I am going to check the water levels this weekend. From the great advice I always get on this forum, I do expect the water levels to fall faster with the DPI US Battery setting than with my old powerwise charger.

Any idea how long a typical charge cycle is taking for your setup?

[JMGreco]

It depends on my use. I have been following Scotty B's break in procedures and charging the pack at the end of the day and letting it charge fully before use. Since I am charging at night, it is fully charged in the morning but I don't know exactly how many hours it has been taking. I did notice that after very little use (less than 1 mile) and then back on the charger, that cycle was done in approximatley 4-5 hrs.

[JohnnieB]

We may be discovering how well the QE was actually charging the pack.

After completing the Pre-Qualification phase, the Yellow LED (Charging) should have came on steady and the ammeter stayed at Max amps for a few minutes to an hour or so depending on the SoC when plugged in. (Phase-2 Constant current Bulk).
When the rate of voltage change decreased to a predetermined rate, that voltage was maintained and the current was allow to fluctuate. In your case it was 61.7V, but that may change as the batteries age and other conditions change. At this point, the ammeter should start going down to and will stay at about 5A and stayed there for a while. (Phase-3 Constant Voltage absorption charge)

When the Amp flow reduces to a predetermined rate, both the Yellow and Green LEDS will illuminate (Meaning the batteries have reach a 80%-90% SoC) and the charger will go into the the Finish stage (Phase-4 Constant current) and the voltage will increase until dV/dT (Change in voltage over change in Time) criteria are met and when it is the charge cycle is complete.

At this point, just the Green LED (and Red Power Led) is on and the charger is now in Float charge mode, where it will stay forever and always unless unplugged or AC power is lost. The Float charge voltage will probably be in the 53-54V range.

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Be sure to keep an eye on the electrolyte level. If the batteries have never been "Fully" charged, they are going to gas a lot the first few charges with the DPI. (Use distilled water only)

[sportcoupe]

Originally Posted by JMGreco

What you described is how my pack charges with the same charger and same batteries. My guess is that the old Power Wise charger was not capable of charging the US Batteries to the proper specifications and the new DPI charger is doing what it is suppossed to do.

[jbrzezinski14]

Johnny B, you're correct, it seemed almost stuck at 61.7v and just under 5A for hours. You're the expert here and I'm still learning, so let me ask you a question: can a pack read 51.2v after charging and not be fully charged? Even according to US Battery, 51.2v is 100% SoC. Could two different battery packs (of identical batteries) read the same voltage but one pack is storing much more energy than the other in the form of amp-hours?

Update: The charger is now floating the batteries at 53.0v. I checked the water level and it seems unchanged so far, I'll check it again after the first few charge cycles with this beast. If you unplug this charger when the batteries are fully charged, then plug it back in a few minutes later, will it go through the whole cycle again lasting a few hours?