RXV Auto-Brake Problem III

[sltintexas]

I'd suggest starting a new thread. This one is 51 pages long and from 7 years ago. Your question may get lost.

[15clubs]

Did you check your battery voltages?

[cartboy]

Me again.



We're at that "Two Years In" point for the third time, and two years since we started servicing batteries with distilled water, and never anything else.

We have a guy on the staff that never likes the way we do anything, and changes everything to however he wants to, often with disastrous results. Yesterday he said something like, "Well that way your doing the batteries sure isn't working. That was a big waste."

I'm used to him being a rear-end, so that didn't bother me, but the thought that he was going to appoint himself to undo what we're doing in this case does bother me, so I talked to the GM today.

Yeah, he thinks our massive battery problem is about to hit us all over again, but, no he doesn't want us to change what we're doing, because he wants to eliminate the "Bad Water" factor from the equation.

I told him I "had records", and I would go look at where we were at the End-of-2-Year point on our last fleet. So, now I'm here looking at "my records."

Yes, we were having problems two years ago, 4 to 10 carts always in time-out waiting for new batteries each day. Then, our tech reprogrammed them to slow them down, and the battery failure rate slowed down.

A year later, and the end of the third year, 127 of 256 batteries had been replaced, and that is the year we are entering next month.

[cartboy]

I am not special, so what I think doesn't have any application other than in my own work.

I have tried to share my experiences. In three years of maintaining a fleet of 60 Club Car Precedents, I don't recall that we ever replaced a battery. In the year that I maintained 67 of the lesser model Club Cars, including 13 that were quite old, we never replaced a battery.

As for EZGo RXV's, I was told that the 2008's I maintained were the first 60 that came off the line that went to a golf course with the brand new autobrake and all the faults and quirks associated. I have subsequently maintained 65 2012s and 65 2015s, each with their bit of improvements.

Here's what I think.

First, and foremost, I believe the autobrake puts a strain on the batteries that carts not so equipped don't have.

I believe there is a State of Health level of a battery at which it deteriorates at a much quicker pace. For a 12 volt, I believe this happens somewhere around 12.2 to 12.4, fully charged. Take a cart off the charger fully charged, let it sit for 1/2 hour for the charge to settle out, and take the readings.

The State of Health is a "measurement" that reflects the general condition of a battery and its ability to deliver the specified performance compared with a fresh battery. It takes into account such factors as charge acceptance, internal resistance, voltage and self-discharge.

A new, fresh battery will be 12.8 or 12.9, and at a good State of Health. As the battery gets used, that will diminish. Do the same process, and after awhile the batteries will be 12.6 "fully charged." Then they will be 12.4.

What that means is that they won't do what they did when they were brand new and fresh. They won't go as many holes or as many rounds because they discharge quicker.

Not only do they discharge faster, but they deteriorate faster. So, once they won't do 36 holes, they won't 18 holes a lot quicker than they wouldn't do 18.

At some point, they hit a wall, and discharge extremely fast. They hit their end of life.

Our RXV batteries have been beginning to fail by the end of the second year, around 10,000-12,000 AH, when they carry a 4-year, 25,000 AH warranty. Then third year has been one of massive failures.

I believe you can anticipate that forthcoming massive failure by taking "fully charged" readings. If you check the carts sitting in the staging area before they go out for the day, and they are reading 12.2 or 12.3 or 12.4, somewhere around in there, it's about to happen.

I believe the RXV causes faster discharge and faster State of Health reduction than carts not having an autobrake.

[cartboy]

Kinda funny, but the way real-life goes, I met our new tech last week, and he said a couple things that made we wonder.

Without going back 51 pages I started this in 2009 because I was trying to find someone else having the same problems we were. We had what I believe to be the first fleet of RXVs to come off the assembly line, and they had a lot of problems. Then we've had a fleet of 2012s, and now a fleet of 2015s.

There, you didn't have to review 51 pages.

So, I asked our new tech today, "What were you doing in 2009?"

He said, "I was in high school."

I asked, "What were you doing in 2012?"

He couldn't recall.

I said, "So, what you know about this model, and all the problems associated with it you have learned how?"

He said, "All I know is that I have replaced a lot of US Battery batteries."

So, that is the extent of his focus and understanding.

I told him that if he needs it, I can tell him anything about an RXV from firsthand experience since June, 2009.

He load tested five carts, and two or three of them failed while we were talking, and after he checked the individual batteries he said, "It was the ones you said."

So, hopefully, I will have the same relationship with him as with our last, very good, tech. I can tell him how many batteries to bring.

To repeat what I said recently, we had not had the catastrophic failures we had at the end of the 2nd year with our 2012's; we don't have 4-10 carts in time-out every day waiting for batteries.

I can't foresee the future, but I can apply science to take a guess at it.

(knocking on wood)

[cartboy]

Originally Posted by cartboy

A year later, and the end of the third year, 127 of 256 batteries had been replaced, and that is the year we are entering next month.

I had the pleasure of meeting with our "regular" tech, the one I have been working with the last few years.

He mentioned that he replaced 139 batteries in our 2012 fleet, so that would probably be about right by the time we got that fleet replace with the 2015s.

I don't have a firm grasp on how many we had replaced by this same time (beginning of the third year) in the 2012 fleet, but it was a lot. I showed him my log where it said we had 13 carts in timeout waiting for batteries.

He said he has only replaced 12 in our current fleet. I agree, and that's exactly what I have told the GM.

Take at look at my auto-fill thread.

[cartboy]

Originally Posted by cartboy

I had the pleasure of meeting with our "regular" tech, the one I have been working with the last few years.

He mentioned that he replaced 139 batteries in our 2012 fleet, so that would probably be about right by the time we got that fleet replace with the 2015s.

I don't have a firm grasp on how many we had replaced by this same time (beginning of the third year) in the 2012 fleet, but it was a lot. I showed him my log where it said we had 13 carts in timeout waiting for batteries.

He said he has only replaced 12 in our current fleet. I agree, and that's exactly what I have told the GM.

Take at look at my auto-fill thread.

I should point out the it's not an "Apples for Apples" comparison of how many batteries have gone bad for our last fleet and our current fleet.

In the last fleet, batteries were "culled". The batteries that did not test bad were saved, and paired with other batteries that did not test bad, and then put back into carts. Typically, one battery would be bad and 3 would be good.

So, when he said that 139 batteries we replaced, he means that 139 batteries actually went bad.

With our current fleet, that is not the case. Batteries are not being "culled" now. The original batteries in this fleet are US Battery batteries, and they are being replaced with Trojans. If one battery goes bad, all four are being replaced with Trojans.

So, when he said 12 batteries have been replaced, that is because 3 batteries went bad.

Right now we have one cart with one bad battery, but it will get four Trojans.

[cartboy]

The next generation has started.

I have opened communications with the person taking care of 150 RXVs with lithium batteries. They've had them for about a month.

[cgtech]

These are a whole different animal for batteries & battery management (slightly different controller too, no swapping from lead carts). Lithium BMS has it's own solenoid to shut down the party. Will be interesting.....

[smokey tennis shoe]

I just saw 4 txt carts that have the new samsung lithium set up. These 4 carts were on various courses for 5 years with the seat bolted shut so no one would get to the batteries for 5 years.

When we opened them up, these 5 year old lithiums were all still at 97% capacity. amazing.

They are not available to the public yet, just to golf courses. We changed out the packs and bms, for practice, it took about 15 -20 minutes for a complete change out.

If your course have these lithiums, you better find stuff to do with your time, like doing alignments etc, no more battery babysitting.