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The NEW Magic Mountain

NYDB

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just got a ride on red with the youngest. a bit of a herky Jerky affair. they stopped loading it after a bunch of chairs because it wasn't running quite right. hopefully it's a minor issue and it runs tommorow.

snow was amazing on the top half
 

skithetrees

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just got a ride on red with the youngest. a bit of a herky Jerky affair. they stopped loading it after a bunch of chairs because it wasn't running quite right. hopefully it's a minor issue and it runs tommorow.

snow was amazing on the top half
Hoping for the best on that. Not to speculate too much, but seemed like the drive was surging once the lift was fully loaded. Hopefully a minor hiccup that can get resolved over night. Was nice to be up top!
 

Newpylong

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I bet they found some issues with the new drive that will need to be addressed before it loads customers again. It's pretty typical when you pair it with an old motor. Gotta get in the PLC to do the fine tuning. Getting the load test done is clutch the rest is minor!
 

skithetrees

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I bet they found some issues with the new drive that will need to be addressed before it loads customers again. It's pretty typical when you pair it with an old motor. Gotta get in the PLC to do the fine tuning. Getting the load test done is clutch the rest is minor!
Pretty much exactly what magic said on Facebook. I was on the lift and it started surging pretty badly as soon as it was 2/3 loaded. They stopped it, tried again a few times but it kept surging. Was run at slow speed to unload everyone, with no surging issues.
 

JoeB-Z

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The surging was rather dynamic. I was watching the sheaves and they didn't quite come to a stop each time. I wonder why this didn't show up in the load test.
 

cdskier

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I'm rather enjoying reading some of the comments from a few random haters on Magic's FB page. I wonder which one is Hugh under another name!
 

skithetrees

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The surging was rather dynamic. I was watching the sheaves and they didn't quite come to a stop each time. I wonder why this didn't show up in the load test.
That’s what surging is. Not stop/start, but a somewhat rhythmic variation in rpm. Wouldn’t have showed up in the load test as that was largely static. The barrels are loaded in a stop start process and the lift only runs a few feet under full load before the emergency stop is hit. They will figure it out, just frustrating.
 

Newpylong

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Yep, even once the barrels are all filled the chair does not really operate at "normal" speed for long. Just long enough to apply the service brake, the emergency brake and APU brake. Then it runs slowly start/stop again to dump them out at the top. Remember it's meant to simulate safety mechanism with a full load, the drive and/motor is not really a safety mechanism. The loaded chairs can't go past the last tower per lift spec so it can't operate normal speed for all but a few feet.
 

zoomzoom

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a load test is necessary to demonstrate that the electronic drive can accelerate and control a fully loaded lift from a stopped condition. it's common for the drive to be "tweaked" a few times during the barrel loading process. once fully loaded there are typically a number of empty chairs at the top, to provide running and stopping room for each braking system to be tested. the missing mass from these empty chairs would be spread out over the length of the lift. if all goes to plan, the last loaded chair is at the unload station at the end of the braking tests. the various rollback devices will be tested at this time, then the apu is coupled up to demonstrate it too can accelerate and control the load.

once fully loaded, the deceleration rate of each braking system is noted and checked against the national standard. adjustments are made as needed, and the lift may need to be slowly allowed to reverse direction if needed. the braking time must be between the minimum and maximums, as too long a stopping distance may be equally as bad as too short a stop distance. regen drives on both fixed-grip and detachable grip chairlifts are common these days. on lifts with regen drives, the drive slows the lift in a controlled manner and the service brake only applies as the lift comes to a stop. to say that the drive/motor is not really a safety mechanism depends on your def of safety system i guess. the lift drive monitors speed, maintains / controls acceleration rates (and decel rates with a regen drive) under varying load conditions, and i'd say it's an inherent part of the safety system.
 

IceEidolon

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Red's not exactly a spring chicken, and nobody's mentioned any Regen braking capability. Regardless, if they're it able to run a couple hundred feet at full power spread over a couple starts and stops, I'm not surprised a subtle oscillation wasn't caught right away
 

Newpylong

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a load test is necessary to demonstrate that the electronic drive can accelerate and control a fully loaded lift from a stopped condition. it's common for the drive to be "tweaked" a few times during the barrel loading process. once fully loaded there are typically a number of empty chairs at the top, to provide running and stopping room for each braking system to be tested. the missing mass from these empty chairs would be spread out over the length of the lift. if all goes to plan, the last loaded chair is at the unload station at the end of the braking tests. the various rollback devices will be tested at this time, then the apu is coupled up to demonstrate it too can accelerate and control the load.

once fully loaded, the deceleration rate of each braking system is noted and checked against the national standard. adjustments are made as needed, and the lift may need to be slowly allowed to reverse direction if needed. the braking time must be between the minimum and maximums, as too long a stopping distance may be equally as bad as too short a stop distance. regen drives on both fixed-grip and detachable grip chairlifts are common these days. on lifts with regen drives, the drive slows the lift in a controlled manner and the service brake only applies as the lift comes to a stop. to say that the drive/motor is not really a safety mechanism depends on your def of safety system i guess. the lift drive monitors speed, maintains / controls acceleration rates (and decel rates with a regen drive) under varying load conditions, and i'd say it's an inherent part of the safety system.

As you said, that depends on age of the drive itself. None of ours had regen, they are on or off so they are not safety mechanisms. They either propel the lift forward or not. Stopping the lift was the job of the service brake, the emergency brake and in the worst case scenario, the drop dog(s).

For new lifts with regen, absolutely, they are the first step in a line of safety mechanisms. Don't know what Red has...
 

zoomzoom

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for further discussion i'd opine that the cable tach is a critical part of the drive system, as it gives input to the motor drive. the lift shall slow and stop automatically if line speed exceeds +10%, and the bullwheel brake shall apply if line speeds exceed +15% or reverse rotation is detected. the cable tach is part of the drive, a safety device in my view. but i'm old and cratchety. : )
 
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