This lift replaced a Garaventa CTEC detachable triple and opened in January 2023.Drive terminal in the Albion base area.Side view of the LPA bottom terminal.Lift overview.Loading area with queuing gates.Another view of the drive station.Leitner-Poma tower head.View riding up the line.Tower 15.Arriving at the top terminal.Unloading area.Another view of the top station.View down from the summit.Looking down the relatively flat lift line.Middle section of the line.Tower 9.A tower with combination assemblies. No hold down only towers on this lift.View up at tower 6.Lower part of the line.Tower 1.Lower station overview.Six place chair with individual seats.Riding up the line.Top station with maintenance rail and work chair.Leitner DirectDrive.Motor room overview.View out the bottom terminal.
Not uncommon for the haul cable to stretch after install and it’s break-in. If the terminal can’t tension enough, they’ll eventually do a re-splice in the off season.
Ryan- Not really. While stretch during break-in after installation is expected, the position of the tensioning carriage/bullwheel and the high and low tensioning pressures (in the case of hydraulic tensioning) are electrically monitored by the lift’s safety circuit. If there is something outside of the design operating range (‘can’t tension enough’) the lift will be stopped. These parameters are checked daily by Lift Maintenance, so they know if they are running out of carriage travel and plan accordingly. This is why you will see lifts that are re-spliced mid-season if necessary. Hope this helps.
Thank you for the correction and teaching us, I had based my assumption on previous comments I had seen regarding new lifts having to get re-spliced mid-season or in the off season after it’s first use. I better understand now.
While this is true, the sag pictured here is not due to a lack of tension. If the lift was out of carriage travel it would not be able to operate and my counterparts would have to set up for the dreaded midwinter resplice.
Likely the operating tension is correct. But that span looks like it could use a little higher design tension and bigger rope.
The point loading (rope deflection at grip) seems to have a pretty sharp angle on those two carriers in the picture. Definitely looks saggy even with deep snow and probably bouncy on a stop??
Some questions for those that work with these direct drives.
How much does the unit weigh?
Are they AC or DC and what is their operating voltage?
What is their normal operating current at design speed and how much current do they draw on startup?(I guess this will vary lift to lift and also how loaded it is)
How overrated are they compared to their expected loads?
Are they supposed to be more efficient than an identically designed lift with a traditional motor and gearbox? Or are they now being used for less maintenance and upkeep due to lack of gearbox?
What kind of evac options are they typically paired with? I think I’ve seen some on here with large gensets if the power goes out. But do they also have direct to bullwheel hydrostatic drives if the motor fails or something similar?
I don’t know the weight directly. But these are (generally) 480v AC synchronous motors. They’ll spin around ~13 rpm at full speed.
Current depends on a lot of things. Typically starting current will be lower than a regular AC motor though. You will see more current when starting though, since it takes more work to get the whole lift moving from a stop.
They’re rated for the power they can put out, so they’re not necessarily overrated any more than any other lift motor. But there are other circumstances that might dictate how the motor is sized. For instance, Ramcharger has a larger motor than would be needed for normal operation since during parking or feeding carriers it’s so unbalanced and takes the larger motor to handle that additional load.
Yes, they’re more efficient than a traditional gearbox setup. They’re no longer converting as much electricity into heat and vibration in the gearbox.
Typically there’s a ring gear inside the drive bullwheel that some other motor/drive system will act on. ANSI wants an evacuation drive to be a different kind of power source, so diesel powered hydrostatic is a good option. A diesel genset running the regular motor is a good standby option, but still leaves the AC drive, motor, and associated controls and cabling as a single point of failure, so something else is generally required.
To glom on to Chase’s comments- our Eagle and Flyer’s motors typically spin at 23 RPM. On startup they’ll both draw upwards of 1300 amps- the Flyer is bigger overall but the Eagle pulls more weight. After initial startup, I’ve seen the Flyer pull 1150 at full line speed with full load. Both of ours have electric evac motors that engage the bullwheel ring gear, and which are controlled via separate drives from the direct-drive motor. Everything else I’d add is quite similar to his writeup.
Gondola at Winter Park is roughly similar to F and O-1 in regard to RPMs. Gondola at Winter Park is 25.42RPMs, because the max line speed is 1100FPM. The Gondola also has electric evac motors, and a bull wheel ring gear.
Question on a e stop, seeing how a direct drive has no driveline inertia, how does the e-stop work cutting the power while still providing a gradual stop not a sudden one that such a system would normally generate?
Chuck- the e-brakes have a couple modulating valves rather than the traditional full dump. They work in tandem to allow a more controlled and smoother e-stop. One allows pressure from the accumulator to keep the brake partially open, and the other can rapidly open and close so as not to lose pressure rapidly.
John, I was not wondering about the brakes themselves (I still occasionally design hydraulic systems) but the actual Direct drive motor. I have been told that a direct drive would stop the lift shorter than any brake system if the power is just cut off instantaneously and that some sort ramped down power feed is needed to prevent motor lockup, I was wondering if they use the drive or some other electronics to achieve the decel ramp or if I have been misinformed about the nature of the motor.
On an emergency shutdown the power to the electric motor is typically disconnected. A typical AC/DC motor will go torque less when the power is disconnected from it.
One of the early concerns about the Direct Drives was over braking (to high of a deceleration rate)
Mainly due to the lack of high speed rotating mass. The electric motor rpm on a Direct Drive spins the same RPM as the Drive Bullwheel. Somewhere between 20 and 25 RPM. A conventional set up with a gearbox input spinning up to 1750 RPM. Most have a huge brake disc/flywheel. The high speed rotating mass helps keep the lift from decelerating to fast when the power to the electric motor in disconnected.
I am not sure if they use some stored energy in the Direct Drive system to overcome this or not??
Lift Blog 
Those are definitely very quiet Direct Drives.
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That’s some serious rope sag there in pic #15.
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I count three fully-loaded chairs. Not surprised.
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I wonder if they’d benefit from having an infill tower in that location.
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I dont remember it being that way, I was on it with every chair at full capacity
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it was significantly more crowded when I went and that was just the day after it opened
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Not uncommon for the haul cable to stretch after install and it’s break-in. If the terminal can’t tension enough, they’ll eventually do a re-splice in the off season.
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Ryan- Not really. While stretch during break-in after installation is expected, the position of the tensioning carriage/bullwheel and the high and low tensioning pressures (in the case of hydraulic tensioning) are electrically monitored by the lift’s safety circuit. If there is something outside of the design operating range (‘can’t tension enough’) the lift will be stopped. These parameters are checked daily by Lift Maintenance, so they know if they are running out of carriage travel and plan accordingly. This is why you will see lifts that are re-spliced mid-season if necessary. Hope this helps.
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Thank you for the correction and teaching us, I had based my assumption on previous comments I had seen regarding new lifts having to get re-spliced mid-season or in the off season after it’s first use. I better understand now.
LikeLiked by 1 person
While this is true, the sag pictured here is not due to a lack of tension. If the lift was out of carriage travel it would not be able to operate and my counterparts would have to set up for the dreaded midwinter resplice.
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Likely the operating tension is correct. But that span looks like it could use a little higher design tension and bigger rope.
The point loading (rope deflection at grip) seems to have a pretty sharp angle on those two carriers in the picture. Definitely looks saggy even with deep snow and probably bouncy on a stop??
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I concur. Does seem like that’s the design norm on LPOAs these days.
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have been riding this lift a lot and can confirm it is pretty bouncy when it stops in certain points
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Some questions for those that work with these direct drives.
How much does the unit weigh?
Are they AC or DC and what is their operating voltage?
What is their normal operating current at design speed and how much current do they draw on startup?(I guess this will vary lift to lift and also how loaded it is)
How overrated are they compared to their expected loads?
Are they supposed to be more efficient than an identically designed lift with a traditional motor and gearbox? Or are they now being used for less maintenance and upkeep due to lack of gearbox?
What kind of evac options are they typically paired with? I think I’ve seen some on here with large gensets if the power goes out. But do they also have direct to bullwheel hydrostatic drives if the motor fails or something similar?
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I don’t know the weight directly. But these are (generally) 480v AC synchronous motors. They’ll spin around ~13 rpm at full speed.
Current depends on a lot of things. Typically starting current will be lower than a regular AC motor though. You will see more current when starting though, since it takes more work to get the whole lift moving from a stop.
They’re rated for the power they can put out, so they’re not necessarily overrated any more than any other lift motor. But there are other circumstances that might dictate how the motor is sized. For instance, Ramcharger has a larger motor than would be needed for normal operation since during parking or feeding carriers it’s so unbalanced and takes the larger motor to handle that additional load.
Yes, they’re more efficient than a traditional gearbox setup. They’re no longer converting as much electricity into heat and vibration in the gearbox.
Typically there’s a ring gear inside the drive bullwheel that some other motor/drive system will act on. ANSI wants an evacuation drive to be a different kind of power source, so diesel powered hydrostatic is a good option. A diesel genset running the regular motor is a good standby option, but still leaves the AC drive, motor, and associated controls and cabling as a single point of failure, so something else is generally required.
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To glom on to Chase’s comments- our Eagle and Flyer’s motors typically spin at 23 RPM. On startup they’ll both draw upwards of 1300 amps- the Flyer is bigger overall but the Eagle pulls more weight. After initial startup, I’ve seen the Flyer pull 1150 at full line speed with full load. Both of ours have electric evac motors that engage the bullwheel ring gear, and which are controlled via separate drives from the direct-drive motor. Everything else I’d add is quite similar to his writeup.
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Gondola at Winter Park is roughly similar to F and O-1 in regard to RPMs. Gondola at Winter Park is 25.42RPMs, because the max line speed is 1100FPM. The Gondola also has electric evac motors, and a bull wheel ring gear.
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Question on a e stop, seeing how a direct drive has no driveline inertia, how does the e-stop work cutting the power while still providing a gradual stop not a sudden one that such a system would normally generate?
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Chuck- the e-brakes have a couple modulating valves rather than the traditional full dump. They work in tandem to allow a more controlled and smoother e-stop. One allows pressure from the accumulator to keep the brake partially open, and the other can rapidly open and close so as not to lose pressure rapidly.
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John, I was not wondering about the brakes themselves (I still occasionally design hydraulic systems) but the actual Direct drive motor. I have been told that a direct drive would stop the lift shorter than any brake system if the power is just cut off instantaneously and that some sort ramped down power feed is needed to prevent motor lockup, I was wondering if they use the drive or some other electronics to achieve the decel ramp or if I have been misinformed about the nature of the motor.
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On an emergency shutdown the power to the electric motor is typically disconnected. A typical AC/DC motor will go torque less when the power is disconnected from it.
One of the early concerns about the Direct Drives was over braking (to high of a deceleration rate)
Mainly due to the lack of high speed rotating mass. The electric motor rpm on a Direct Drive spins the same RPM as the Drive Bullwheel. Somewhere between 20 and 25 RPM. A conventional set up with a gearbox input spinning up to 1750 RPM. Most have a huge brake disc/flywheel. The high speed rotating mass helps keep the lift from decelerating to fast when the power to the electric motor in disconnected.
I am not sure if they use some stored energy in the Direct Drive system to overcome this or not??
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I’m not sure either. Now I’m curious- I’ll have to ask our sparkies today, if they know.
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