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Author Topic: Battery Problem?  (Read 29185 times)

Radjack

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Battery Problem?
« on: May 10, 2011, 01:26:32 PM »
Hey guys,

I got Bubba out working this week and have noticed a serious decrease in the length of his work time per cut..
I think it was around 2-2.5 hours last year per outting, where this year it seems to be between 48-69min. The display reads about 2880 after charging 12 hours, where last year it read 2950 or so.

Any thoughts?
Battery is 10 months old. This was its first winter, i charged it 2-3 times over winter to keep it full.
Anything i can do as far as testing?
I think batteries have one year warranty?correct?
Thanks

Botman

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Re: Battery Problem?
« Reply #1 on: May 10, 2011, 06:11:57 PM »
Maybe battery.  What model do you have?  You might want to check if your charger is indicating a fast charge(red light instead of green).  I had a similar problem and needed to replace the Battery charger and that fixed the problem.

Radjack

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Re: Battery Problem?
« Reply #2 on: May 11, 2011, 09:40:08 AM »
Talked to kyodo today, I guess there is a feature that limits the bots runtime when the grass is sparse... He suggested that when the grass gets longer he should stay out there longer.
All the voltages where fine, just need longer grass!
Phew!!

RobotLady

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Re: Battery Problem?
« Reply #3 on: May 12, 2011, 02:11:57 PM »
My standard answer about this is "What does the lawn look like?"  If the run time is short, but the lawn looks great, there is no problem.  If the lawn is not being maintained when it worked fine in the past, then there could be a problem.  The battery getting old is the most likely cause.  You can also try shining up the plates and recharging nuts to ensure they are making good contact.  Poor contact could affect the charging time, too.

Radjack

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Re: Battery Problem?
« Reply #4 on: May 16, 2011, 10:53:54 AM »
Update**

I kept a close eye on Bubba all weekend, and after 30-60 min, he would head back to charger with low battery. After charging for 12 hours the battery only got up to about 28.5 volts or so, i guess it should be closer to 29.5V...Called kyodo today and they sending out a new Li Ion battery today since it is less than 1 year old and still under warranty...
Not sure why the battery didnt winter well but hopefully this gets him working like new again. I charged him for 10-12 hours 2 or 3 times throughout the winter, to keep him fully charged.
Will keep you updated after i get the new battery.

toolbelt

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Re: Battery Problem?
« Reply #5 on: May 16, 2011, 09:28:30 PM »
I charged Junior's battery about every 2 months throughout the winter but it only took about 1/2 hour for the voltage to get back up to 29. 

RobotLady

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Re: Battery Problem?
« Reply #6 on: May 23, 2011, 03:35:37 PM »
28.5V after charging is odd.  It makes me wonder if there is a problem with the power supply.  You can check the output voltage of the power supply by disconnecting the round connector (press the metal tab and then pull it out of the transmitter).  Put the meter probes across both pins while it is turned on being careful not to short the probes to the metal connector housing.  You should get something between 29.3 or 29.5V.  If so, the power supply is fine.  If you get 28.5V, the new battery will only charge that high, too.

Radjack

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Re: Battery Problem?
« Reply #7 on: May 24, 2011, 09:47:56 AM »
The 2 charging plates in the house had a voltage of 29.5 when we tested it...

I got the new battery this morning and hopefully will get a chance to install it and run bubba.

Update...
Installed new battery and he is charging up as I type, hopefully by tomorrow I will be able to see what happens with the new battery.

Update...
It has been 19 hours of charging and the battery is still at 28.6V. I will leave it to still charge a bit longer but I am pretty concerned that something else is wrong for it not to get up over 29V.
The plates are reading a solid 29.43V, any ideas why this new battery won't fully charge just like the old one?
I should also mention that there is a splice in the wire from the ac adapter to the charging station, but since the voltage is a solid 29.43, I don't think that should be an issue.
I am sitting at work thinking about this problem and wondering about the contact between plates and the knobs...could the plates be dirty, or they just arnt making good contact? could there be a voltage regulator problem?

Will keep updating...
« Last Edit: May 25, 2011, 10:41:10 AM by Radjack »

Radjack

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Re: Battery Problem?
« Reply #8 on: May 26, 2011, 09:15:22 AM »
Went home and cleaned all the terminals up, let it charge all night and he got up to 28.9V this morning...
I think i will just let it keep sitting there "paused" and charging until the Voltage stops rising, maybe a new battery takes longer than i thought to get up to full charge.

gyro

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Re: Battery Problem?
« Reply #9 on: May 26, 2011, 10:47:36 AM »
If you have the FM filter inline with the charger I would recommend that you remove it.

Radjack

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Re: Battery Problem?
« Reply #10 on: May 26, 2011, 12:03:50 PM »
It has been in line with charger since i got the system. It seemed to work fine all last year.
Why would I remove it?

Radjack

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Re: Battery Problem?
« Reply #11 on: May 26, 2011, 01:50:19 PM »
it maxed out at 28.9V.....
I let him run and got 91 min run time....
I am not sure what to do next, waiting on a call back from kyodo for more ideas...

gyro

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Re: Battery Problem?
« Reply #12 on: May 27, 2011, 10:12:25 PM »
In my case the FM filter effected the charge reading of the battery to the charger. It kept dropping the charger output to a maintenance level and would not bring my battery up to full charge. Just unplug it and give it a try. You can't hurt anything by removing it.

RobotLady

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Re: Battery Problem?
« Reply #13 on: May 29, 2011, 08:55:47 AM »
Also, where are you reading the battery voltage?  The best place is on the display.  After the robot gets going, it flashes the battery voltage (4 digits). 

Radjack

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Re: Battery Problem?
« Reply #14 on: May 29, 2011, 10:40:31 AM »
If that was the case for me gyro, the charging plates would not read 29.43 V correct?
It seems to me that the problem either lies inside the robots charging system, or the battery itself. The max charge is regulated and not allowing the battery to fully charge.
Kyodo is sending me a third battery, as they think it is the batteries as well...
We will soon see when I get a third one...


Battery voltage is read using a meter across the terminals, but I always keep an eye on the display as well for quick reference. It has always been the same value. (or darn close)
Will keep you updated...

 

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