The Forestry Forum

General Forestry => Sawmills and Milling => Topic started by: jcbrotz on March 18, 2014, 05:56:51 PM

Title: Woodmizer alternator current draw ??
Post by: jcbrotz on March 18, 2014, 05:56:51 PM
SO the story goes I burnt up my alternator today, At the shop I got a fresh one and was lectured on the draw the hydraulic system puts on the alternator. I have never checked the draw on the alternator but why would I it was working fine :D. So I install the new on and am getting around 110 when running the hydraulics and 115-118 when running the hydraulics and the up /down motor. Has anybody ever checked the current draw n the alternator before?
Title: Re: Woodmizer alternator current draw ??
Post by: ladylake on March 18, 2014, 07:11:01 PM
 Make sure you have a good battery , with a weak one the hydraulics will rely more on the alternator.   Steve
Title: Re: Woodmizer alternator current draw ??
Post by: Brucer on March 19, 2014, 12:00:53 AM
Haven't had to replace the alternator yet, after 2300+ hours.

If your battery has a full charge it will take the peak load off your alternator. I make a point not to shut down the engine every time I have to do some material handling, such as rolling a timber off the mill. Leaving it running for the extra few minutes will top up the charge on the battery. Shutting down every time you're handling wood means you'll be draining the battery more often.
Title: Re: Woodmizer alternator current draw ??
Post by: jcbrotz on March 19, 2014, 04:43:26 AM
Guess I should give up a little more details, the battery is a year or so old and the mill has 2700 hours on it. I believe the battery is in good condition, it starts the mill (Kubota diesel) like new and the alternator drops back to "normal" load of 13-15 amps within seconds of releasing the hydraulic levers. Kinda interesting to see what draws what for amps, I guess I need to write them down for future reference so I know the next time what needs some attention. I will try and find time today and call woodmizer and find out what they think it should be. I cant complain about 2700 hmm make that 2800 hours but I can still ask ??'s on it.
Title: Re: Woodmizer alternator current draw ??
Post by: Magicman on March 19, 2014, 08:05:40 AM
You do not have your sawmill information in your profile, but with the Kubota, I assume that it is a SuperHydraulic?

If so I believe that it has a 150 amp alternator.  The idle speed is set at 1500 rpm to insure that the battery is always getting a full charge.
Title: Re: Woodmizer alternator current draw ??
Post by: Jim_Rogers on March 19, 2014, 09:16:51 AM
When I got trained on my WM mill back in 94 they told me to never run the hydraulics without the engine running.
The hydraulics drain the battery down and then the alternator has to bring it back up.

On my machine if the red light on the dash panel is burnt out the battery won't charge.
To test turn on your key but don't start the machine. The red light should be on. When my red light burned out, I didn't have one on hand. I ordered two, one to put in and one to have on hand for next time. I had an extra green so I put that in, instead. Still waiting for that one to burn out.

One time I was running my mill and moving the hydraulics and the engine died. I called tech service to see why. They told me that the battery was weak and that the engine was drawing juice and the hydraulics were drawing juice and there wasn't enough for both due to low old battery. I told him that the battery was a 5 year battery and it had only been in 2 years.
He exclaimed: "you got two years out of a battery?" and I said yes. He said: "we never get two years out of a battery." This is/was due to the fact that the draw on the battery would pull it way down and then build it back up again. He suggested that I get a deep cycle marine battery. I got one of those there and then.

Later on talking to another electrical tech they told me that I didn't need a deep cycle marine battery any more.
I didn't get one the next time I needed a battery. I just got a regular one.

I don't know if any of this is going to help you or not.
But good luck with your machine.

Jim Rogers
Title: Re: Woodmizer alternator current draw ??
Post by: jcbrotz on March 19, 2014, 10:55:03 AM
Thanks, Magic, Think I got my profile fixed, it used to be there but I lost it somehow. The mill is a 2004 lt4033hd, I have the 140 amp alternator. I'm back up and running just curious if anybody has done and current draws on their motors.

Thanks Jim, I hardly ever run my hydraulics without the motor running except when closing up for the day. I see minimal need to start the engine to fold up the arms or run the head up and down, but that said it is a heck of a draw on the system as the hydraulic pump runs around 100 amps or shall I say the alt current goes up to around 110 from around 15, but it drops right back down after the pump shuts down. I will be getting myself a list of the current draws on the machine as I view it as a good trouble shooter for any binding/bearing/pump problems. I may look into a new woodmizer approved battery as when I replaced it I got an optima red hat, I think its fine and think the alternator just gave up the ghost due to use and time. she had 2800 hours on it, I put the mill thru its paces this morning and all seems fine now I got do my taxes now so wish me luck with that. :'(
Title: Re: Woodmizer alternator current draw ??
Post by: backwoods sawyer on March 19, 2014, 11:32:39 AM
I have had more than one or two folks with electrical back ground question how wise it is to run just one battery, with a 200 amp alternator when just the two hydraulic pumps pull 200 amps each and every time the levers are pulled, making the alternator work over time especially when working large logs.
Added a second wire from the alternator to the battery to reduce line loss due to the distance between the two. Considered hooking up the second alternator that is on the Kubota but there was concern of back charging so never pursued that option.   
I use the woodmizer recomended size, style of battery and find I change out a battery once a year, and the alternator is in the shop being rebuilt every 18-24 months  :-\
Title: Re: Woodmizer alternator current draw ??
Post by: sparks on March 20, 2014, 09:06:30 AM

You have a standard hydraulic sawmill. The D33 has a 140amp alternator. With the engine running you should read 80% of alternator out put of around 112 amps. Your voltage output at the alternator should be 14.5 to 15.0 volts. The battery is the key to longer alternator life.
The battery needs to be a 24 group, 1000ca/875cca with a 125amp reserve capacity. The battery will weight roughly 45 lbs.
If you saw every day and you grade saw you can expect to replace the battery every year.

Batteries suitable for the mill:
Deka 24M7
Interstate 24M-XHD
Carquest 24M7
AC Delta C24HP
Exide XXHD-M-24

Thanks all