gas or electric

deadeye · September 08, 2005, 06:33:43 PM

just wanted to find out how much it cost to run my mizer lt40hd with an electric motor. how good does a 220 volt run and how many horse you need. thinking of setting up stationary if the price of gas goes up much more. any input would be nice

Bibbyman · September 08, 2005, 08:05:18 PM

I'm firmly of the opinion that, if you can go electric then do so. We went to an LT40HDE25 Super in early 2002. We had two gas LT40s before. One was a manual LT40 with 18 hp gas engine and the other was an LT40 Super with 35hp gas engine.

Here is a link to some info I put on the knowledge base about how we installed our phase converter. While it's mostly about that, it also has some info as to other things.

Rotary Phase Converter - one example

One limited study showed we were spending about 1/3 as much on electric as we would have been for gas to saw the same amount of lumber. All this is a floating target as fuel prices have jumped quite a bit and the price of your electricity will be different. But in our case, the energy cost savings are clear.

Other costs to consider; Electric motors are less expensive to buy and to run than equivalent fuel engines. They are a lot lest complicated – no oil, filters, plugs, belts, hoses, pumps, etc. to change.

HP? How fast do you want to go? The LT40 was offered with a 15hp 3ph motor in past years. Now it's only available with the 25hp 3ph motor. I'm told that the HP rating is a bit deceiving on an electric motor as can produce as much as twice its nameplate HP under peek load.

It won't be practical to power a Wood-Mizer LT40 with a single phase motor. If they made them with enough HP, they'd be too big and heavy. I think they are putting a 10hp single phase on their LT15. Unless you're updating from say a 14hp gas engine, you'd be pretty disappointed in it's performance on an LT40.

If you have 3ph power available, you're really lucky. If not, it will generally cost an arm and leg to get the power company to put it in. But, you can go with a phase converter like often done and run your 3ph Wood-Mizer from a single phase source.

There has been a lot of Wood-Mizers leave the factory with engines and get converted to electric. I guess it's been done the other way too. There is not much mechanically different from a Wood-Mizer with an engine or one with an electric motor. Wood-Mizer should have all the special parts you would need.

ElectricAl · September 08, 2005, 08:40:55 PM

DeadEye,

Bibs right ;) if you have a chance to go electric you'll love it 8)

Know how the gas engine pulls down in a cut, electric keeps it's rpm steady.

If your mill is a 92-96 with the Onan P24, the electric conversion is pretty simple.

$1200 to 1500 for the sawmill and $3000 to $5000 for a good roto phase converter and a qualified 3 phase electrician.

Don't let the numbers scare you. The more you saw the cheaper it is to saw.

Remember last century when gas was 99 cents

We went from over $400 in gas per month to $50 in electricity at a rate of 5 cents per KW. 5 cents per KW is kinda rock bottom pricing, chances you'll be higher :-\

ElectricAl

FiremanEd · September 10, 2005, 09:09:56 AM

Deadeye,

ditto to what they said above. Electricity is the CHEAPEST power you'll ever buy!! We're putting out roughly 150MBF / month with the mill, edger, blower and chopsaw and the bill is in the mid $300's per month. 8) 8) They highest month ever was $420. The diesel bill for the pickup, loader and road tractor was $2500 though... >:( >:( And that was last month,,, I'm expecting well over $3k this month.... >:( >:( >:( >:( >:(

Ed

WH_Conley · June 25, 2006, 08:59:53 AM

Figured I'd bring this one back to the top and see if anyone else has anything to add. I am at te point that I will have to do an engine replacement shortly. At the price of fuel I am putting over a $100.00 a week in the gas tank. Have 3 phase about 500 feet from the millshed. Don't know the cost yet. Being portable is not really big deal as most of my sawing is at home. Comments please.

Bibbyman · June 25, 2006, 09:17:24 AM

First thing I'd do is talk to the power company. With some it'd probably be no big cost to get 3ph installed. Others may want a minimum usage and you may not use enough to make it cost effective. For example, our company wanted to charge us something like $390/mo minimum service charge. If we used that much power, it'd be no problem. But even now when we're doing a lot of sawing or mill electric bill is less than $100/mo.

In my area, they have 3ph nearby but I don't think they want any 3ph applications because they would then have to keep the phases in line and balanced. Now they can switch loads and phases as needed.

Just need to talk to them. ;)

WH_Conley · June 25, 2006, 09:35:57 AM

Last time I talked to them the man I spoke with talked like it was a small minimium, he was not the man in charge. The lines run across my property to a large mill about a mile up the road. I guess the first thing is to try to talk to the man in charge to get a firm price.

eamassey · June 25, 2006, 11:10:03 AM

Single Phase electric?

I am building a mill with single phase power. My method is two 7-1/2 HP single phase motors belted together. (Identical motors.) This gives 15 elec HP to the blade.

My experience with phase convertors is that you lose 10 to 30% of the nameplate HP. (3-phase motor efficiency really drops if you have any phase imbalance.)

I think my single phase setup will compare with 25 HP gas.

sawguy21 · June 25, 2006, 11:19:55 AM

Unless those motors always run at exactly the same speed, which I doubt, there will be parasitic losses and the belt friction will eat up some power. How many amps due you have available to run them? I am no electrical expert by any means but that does not seem to me to be an efficient system.

Sawyerfortyish · June 25, 2006, 11:29:25 AM

I have 3 phase going up my road but the run to the mill was about 125yrds they wanted 12 grand to do it with a 500.00 minimum usage charge per month they also said they would have to put in some kind of substation at the end of my driveway that was why it was 12 grand. I put in a small 75kw genset that does all I need and it don't burn nowheres near what there minumium usage charge would have been in fuel.

theonlybull · June 25, 2006, 11:55:19 AM

we've got customers using 2 10hp motors coupled togethere to run equipment, and they've been very happy with it.... they used a delay start switch, so they were only starting one 10hp motor.

MartyParsons · June 25, 2006, 09:28:25 PM

We just signed a contarct with Rural Electric Cooperative. The monthly cost is $ 56.25 and .00720 per KWh if we stay less than 25 KW if we reach a demand load of over 25 kW it will be $ 6.25 per kW ( hope this never happens)

The demand for Electric mills has risen since the fuel cost has gone up. If you have no need to be portable it is the way to go.
Marty

amberwood · June 25, 2006, 09:55:59 PM

I had a LT40SH electric demoed over the weekend...and compared to the diesel it was silent bliss.

Instant power-instant silence.

DTR

mike_van · June 25, 2006, 10:03:24 PM

Lots of ??? with that 2 motor deal, do they both start/stop on the same switch? Whats the starting current? Do they have seperate belts to the driven pulley or do you go motor to motor to driven pulley? A clamp on ampmeter will tell you if they are drawing the same amperage when running, but if they aren't, will one burn out from doing all the work? I think theres a ton of questions on this subject, trial & error can be lots of $$$$. One 7 1/2 hp 230V motor will draw a little over 30 amps, 2 would be 60+, start up draw probably double that. A 200 amp single phase service should handle this if it's not a long secondary run, conductor size large enough, etc. But, if you start dimming lights in the area everytime you push that start button, most power co's do have the right to disconnect you until you upgrade to a commercial grade service. Like 400 amp or 3 phase. They will also install a demand meter, more than likley, and your minimum monthly bill will reflect this. Could be a few hundred a month, even if you don't use it. My 2 cents, I would check a lot of this out before I spent money I couldn't get back. Electric is the way to go in my opinion if the mill is stationary, i'm just not sure this setup is.

eamassey · June 25, 2006, 10:31:05 PM

Running two motors-
It is not all that unusual to see machines with two matched electric motors. You just belt them together with matched sheaves. In the sawmill case, I have an air clutch, so there is not even the shaft(s) load for startup. You start one motor at a time-- so the startup load is not much higher than rated amps on the first motor, and there is hardly any start up peak to start the second motor. You really need to use a motor starter of adequate size, rather than just a contactor.

Clutch comment: the clutch I used, Carlton "PowerFlow" is a shaft hung sheave clutch with two groove sheave for B belts, motor #1 has a three groove sheve, with motor #2 having a single groove same pitch diameter as motor #1. I used BX belts to get full horsepower ratings- one belt from motor #2 to motor #1, two belts from motor #2 to the clutch.

joelmar10 · June 26, 2006, 12:20:58 AM

Two motor setup sounds very nice...I'm intrigued. Where did you get the air clutch?

BTW, Welcome to the forum, eamassey!!

Bibbyman · June 26, 2006, 06:54:38 AM

I'd question the weight of two large single phase motors use on a WM mill. Any time I've compared the size and weight of a single phase motor to a three phase, the singe phase motor has been much bigger and heavier for the same HP.

I've been told that the roto-phase converter only reduces your power by a couple of %. You'd probably notice more fluctuation in line voltage than what is lost in the phase converter. If you can go three phase right off the power gird, that'd be the best choice.

WH_Conley · June 26, 2006, 02:17:09 PM

Out of the Grainger catalog; 25 hp, 3 phase 379- 397 lbs-10 hp single phase 159-200 lbs.

Called local co-op, lady said she would have to get a engineer to give me a call back.

Called WM, guy I talked to said to convert to electric between 3 and 4k, asked him which was closest, he did not know, had to talk to his boss who is on vacation ???. No doubt the worst response I have ever received from them.

Don't guess I know any more now than I did. Seems like the only answers I receive are right here. Course that don't really suprise me. ;)

eamassey · June 27, 2006, 10:42:42 PM

Replying to joelmar10 question about air clutch. . . . . . .
I bought the $1000 air clutch on e-bay for $45 plus shipping. The story is a bit longer than that... I wanted a clutch but was convinced that I would not be able (or willing, really) to buy one. So I had designed an air clutch and had about half of the parts machined when I ran across the one on E-bay. The clutch weighs about 65 pounds, good design. It did not have a sheave, so I bought one on e-bay and machined it and an adaptor to fit. Looks great. I think the sheave is a 10.4 pitch diameter for B belts.
The reason for two motors is that 10 HP is as much as single phase goes (normally speaking). I think the motors weigh 136 pounds each. My saw head and carriage is heavy at about 1250#. Heavy is good if you take care of the details. Stability.
EAMassey

Bibbyman · June 30, 2006, 06:04:38 AM

I got to thinking of how we converted from a gas engine to electric motor..... We found another owner for our two Wood-Mizer mills and bought a new LT40HDE25 electric. That may be a better way to convert rather than getting out your wrenches.

If you don't want to upgrade to new, there are quite a number of used E25 Supers out on the market.

WH_Conley · June 30, 2006, 06:21:09 AM

I missed one about a year ago, was not really interested at the time, wierd sale, cash no good, had to have a letter of credit from the bank. I was not interested in the mill, I didn't think so didn't make any arrangements. The thing worked and went for less than 4k. :-\ Boy was I sick.

I want to think Marty Parsons for stepping up and taking care of my WM questions, even though he didn't have to. With people like that the company has to do good.