backup power for elevator?

[dr.zapp]

I have a elevator in my house, and the backup battery is dead- won't charge... the company wants $7000.00 for a replacement, and I'm thinking a generator would be less.. and I could run other things as well. I'm looking at several hard-wired generators- does anyone have such a set-up for back-up power?

[PeteShick]

http://www.norwall.com/

[ancientgimp]

I have a small Briggs and Stratton 7K generator and it is a godsend. They extended my natural gas line to the rear of the house, installed new wiring and panel for generator circuits, now 10 seconds post power failure my selected circuits are powered. Circuits I chose are fridge, microwave, furnace, water pump (have well), garage door as well as most of the light circuits. I can use TV and computers during pwr failures. My oven, rangetop and a/c are not hooked up. The larger Generacs are nice, quiet systems. My generator is a bit louder than I would like. Generators should be serviced and checked a couple of times per year, it's important to have a servicer you trust as well as an installer w lots of experience. In some cases you may have to change out natural gas meter at house if your generator will create a larger demand. Check this out while shopping. if you do not have natural gas to house you will need large propane tank. You will likely have a warning light system in your house to warn you of any malfunction of generator. Your generator will likely exercise itself w/o load for maybe 20 minutes weekly. If you have a prolonged pwr failure you should shut off generator to rest it and check the oil. On mine I have to go outside to shut it off, I am thinking of having a shutoff wired in house for use during blizzards.

[MSspouse]

I would look for someone else willing to work on the lift. It's probably based on standard, industrial sized lead acid battery. They shouldn't cost more than a couple hundered dollars each. I am currently in the process of building a lift based on a "walkie stacker" (lift truck without the truck). It uses only one 12V and will do at least 20 lifts on a charge. And that's on a 5 year old battery. I can't imagine you would need more emergency capacity than that.

An automatic, self-starting generator system is nice but will cost you thousands of dollars. Unless you have other compelling needs, it doesn't seem like it would be worth the expense.

Either way you should have someone look at the elevator. If the batteries are very old they should be removed from the system and the charger disabled if possible. You don't want them boiling dry or leaking. I say "if possible" because the design may depend on batteries. A simple system consisting of a large DC motor may need hundreds of amps. It's doubtful the system has a power supply large enough supply that much current. More likely, it constantly charges batteries and the batteries supply the short bursts of current needed. You would need someone competent to determine if the system can operate without batteries, or with batteries in poor condition. If your lift is slowing down after a few back-to-back runs it most likely needs good batteries to work.

[skippopotamus]

MSSpouse, let's see the lift. I looked into doing something like what you're talking about but ended up using garage door tracks and a chain hoist for my elevator.

[dr.zapp]

thanks for the replies- it's not just a lift, but an actual enclosed elevator (this one here- http://www.premierlifts.com/RevolutionBrochure.pdf I've had a local company look at it (the one I got it from went under), they want $7000 for the new backup battery- it's just plugged inline to the elevator main power (240v 30A line), and only kicks on when there is a power outage, which we just had- 2 days stuck in my house b/c the battery was bad, thus looking for something else. I disconnected the battery now. I realized I also need something to power my garage door- I can't lift it myself- so even if I could get down to the garage I'm stuck w/o an AB close by. And having a working furnace during power outages would keep me from freezing.
I've looked through the generators in that link above- but I'm just estimating how much wattage I need for the elevator based on the motor (3/4 hp 230 VAC 5 A FL 10 A peak) the company that wants to sell me the battery couldn't or wouldn't tell me, and the generator web sites don't list an elevator in their power requirement forms...

[ancientgimp]

The folks giving you estimates on generator should be able to determine what generator could handle the elevator. Ask them to have their installing electrician look at these specs before they price out the generator for you. My small unit cost less than 3,000 including cost of running wiring, installing panel for generator and running the gasline to rear of house.

[SCIfor55yrs.]

I have a 20 kw Briggs & Stratton for my whole house including the A/C. Summer heat is a threat to this quad. Also, I am now using a low air loss bed and the generator saved me twice in the past 3 months. It has been one of the most worthwhile investments I have made. You might contact B&S to help you figure out what you will need.

http://www.briggsandstratton.com/generators-pressure-washers/

[MSspouse]

...this one here- http://www.premierlifts.com/RevolutionBrochure.pdf...

That's a pretty high end elevator. It would need a sophisticated, high power motor controller. Batteries would definitely not be required. Furthermore, since the batteries are rarely exercised, they will be deteriorate quickly. Replacing them is probably a waste of money.

The main issue I would see with a generator is the power quality. Some motor controllers can fault if the power is not pure, 60 Hz sine wave. A friend of mine can't even get his furnace to run on generator power. Best thing to do would be to have prospective vendors come out and demonstrate their unit will work with your elevator.

The garage door is easy. Chamberlin/Liftmaster/Sears have battery backup models. I bought one myself out of safety concern. The only fire escape for wheelchair is through our garage. If my wife was home alone she could not open the door manually.

[gac3rd]

The brochure says that the unit uses a 230V AC motor. So there is apparently high power DC to AC converter between the batteries and the motor. Perhaps this is driving up the replacement cost.

In any case, since this is an AC machine it seems a standby AC generator is a much better solution to the backup power problem than batteries. Especially if you have natural gas or propane already in situ.

The quality of the installation matters, so shop for experience and references.

Retired EE professor.

[MSspouse]

MSSpouse, let's see the lift. I looked into doing something like what you're talking about but ended up using garage door tracks and a chain hoist for my elevator.

Just getting started on the lift project so no pics yet. It's not rocket science though. The biggest challenge will be to get the unit in my basement. It needs to be tipped on it's side to thread through a 3' door. It weighs 1100 lbs. From there I'll frame an elevator shaft lined with 4 vertical stabilizing tracks of angle. Then I'll build a car with bearings to run up and down the angle iron track. The stacker will be positioned under the car and lift from below using the forks. Stackers are very beefy but a little wobbly at the top of travel to just go totally free standing. Not planning any complicated safety brakes since the worst case single failure is a hydraulic line blowing out. The cylinders are large enough, relative to the lines, that the descent wouldn't be much faster that hitting the down solenoid. The chains on the lift mechanism are already redundant so no single point failure there. Frankly, the whole thing is grossly over designed for the amount being lifted. As long as the seals and lines are maintained, I don't see what could ever fail. Fork lifts are designed for decades of heavy service. But, I suppose I could put safety catches at the top of travel to cover the case where you are just entering the car. That could be some manually operated pins operated by the entrance door.

Other home brew lifts could work fine. I went the stacker route because I got a good deal on it. Cost me $500 plus $200 worth of gas to go get it. It looks exactly like this:
http://www.crown.com/usa/products/pdfs/specs/b_spec.pdf
Incidentally, I just finished using it to build my garage. I lifted the roof trusses, a 450 lb girder, and the roof plywood. Not hiring a crane to lift the trusses saved me at least 1/2 the cost of the lift alone.

I'll post pics when I finish. Hopefully I'll get enough time off over the holidays to "git er done".

[Reed-edm]

I've got an elevator in my house, it goes from my room to outside and the basemnt. It's definantly not built to code (safety? not on this thing).. But it's easily maintained by my friends & family when needed.

It runs at 24V DC, I use two Gel celled batteries to run it (charged via a treickle charger), so even if the power goes out I'm never stranded.

For maintance its goes like this:

New cables every 3 years or so ( $100 for 1/4" aircraft cable from home depot).
New selinoids when they go seems 1 every 5 or 6 years ($5 or so)
New batteries every 7 or 8 years ($500 for the pair of new batteries)

Theres a couple companies here that want maintainance contracts here for $300 a year...no thanks, i can look at it and 'listen' to it and know when something is up.

I've never had to replace the motor, pullies, or any of the electronics (aside from an occasional blown selinoid) in 22 years.

[Reed-edm]

thanks for the replies- it's not just a lift, but an actual enclosed elevator (this one here- http://www.premierlifts.com/RevolutionBrochure.pdf

Thats a great looking elevator..

On page 20 of the brochure, it says they don't use any proprietary parts, so everything should be easily found. If anything, look for an electrician or an apprentance on kiijii and have them look at the battery area. they should be able to locate it pretty quickly and identify what battery and parts you would need. It may cost you $100 or so cash, but I can bet you the repair will be under $1000..

Also don't mention the $7000 repair quote until they finish.. ;)