This is originally an Express Lifts DMR, high speed relay controlled lift from the 1970s. It has since been modernised by Otis in the early 2000s, however it still retains its original positioning system on the cartop. At the top and bottom of the shaft are ramps which the roller runs across to alternate which switches are active. Originally, the entire shaft would have been set with these ramps in a ‘ZigZag’ layout. The cartop positioning system would work in sync with the floor selector in the machine room to accurately slow down and level the lift into the floor. After the modernisation, it now only functions as a sort of limit switch. Only one of the contacts are wired in, and it only operates at terminal floors. Here is the original machinery in action: ua-cam.com/video/w0Jy805xYJE/v-deo.htmlsi=QlV4K-z_OJsU9cWi ua-cam.com/video/hz7NvgZaoDM/v-deo.htmlsi=cAP9etFaP6ME09SV
That is only the slowdown box for terminal slowing, the variable transformer on the end reduces voltage to the regulator, the floor levelling system was a well transducer that was switched over from contact 7 on the up down selector panel, as the tapered plate entered the transducer the propertional value due to the plate blocking the AC from to the receiver was fed into the regulator, when both transducers were on the plate evenly the value was reduced to zero, this had a PHL light sensor that shone through a hole in the middle of the plate for door zone confirmation and final stopping, this allowed the drive to run in an S curve to the floor but always overshot slightly and levelled back (this was normal). Much faster than most modern lifts when it was set up correctly. I will see if I can find a picture of a well transducer for you
@@liftguy30 Wow, that’s a lot of design effort just for it to only work at terminal floors! Really interesting to hear about the well transducer. I do remember being told about it some time back. So, the the theory of the ramps in the shaft being set up in a Zig-Zag layout is incorrect, and the only ramps that would’ve ever been there is just at the top and bottom? It would be great to see what the well transducer looked like! Please do let me know if you manage to find the photo!
Polish medium and high-speed lifts (Ward-Leonard drive) make use of actually a similar design but only as limit switches, there are few positions which introduce speed limits as car approaches end of shaft. But here it looks like a more sophiscated device. What is the purpose of this variable air-gap/coupling transformer at the front of this device? It suggests some analog feedback of the car position.
@@LucasTheTechCollector They were original, however Express had begun refurbishing them in the mid 1990s with an electronic despatcher known as the QDOS Overlay System. So all the old controllers are there, but there’s another new Express cabinet to the side with PCBs and a monitor in it handling the calls.
Elevonic 411M? I know of a set of 2 Elevonic 411s that had this exact mechanism as well. Those were fresh installs in the 90s and weren't mods from older lifts
@@LiftyGamez It was the EXACT same? Or just a similar design? That’s really interesting because Elevonic 411 is a microprocessor based controller isn’t it? Also, do you know what other sort of positioning system the Elevonic has as well, or is it just that on its own? Just trying to think why it would need something so complex like that, as I’ve been told that this device is actually only for the terminal floor stopping, and not used as a general positioning. I’m still yet to correct the title and think of what to say lol
@@Lift.Tracker I couldn't see the inside as the box was jammed shut, but when the lifts were still in service it had the exact same design with the long ramps at the top and bottommost floors and the switch on the box. Those had selector tape for positioning too which I thought was a bit odd
@@LiftyGamez Yeah, that does seem odd. Given that Elevonic 411 is microprocessor based, why would it have selector tape as if it has a pie plate selector the same as a relay Otis? Maybe it actually did have a pie plate selector and had a controller like a sort of microprocessor version of this? ua-cam.com/video/RXeF6ZSUbCc/v-deo.htmlsi=OfowVKdRoqc6n9vR I really don’t know much about Otis stuff to be honest. There’s a lot more variety compared to other manufacturers with Otis I think!
@@Lift.Tracker no, as far as I can tell the selector tape probably drives an encoder of sorts, which sends feedback to the controller. I know of 90s Japanese made Otis lifts that have this positioning system as well as some 401s, but never expected it to be used on a 411. Other 401s and 411s use the standard shaft bars without any selector tape, but its hard to tell which positioning system an Elevonic uses without looking into the shaft or motor room
This is originally an Express Lifts DMR, high speed relay controlled lift from the 1970s.
It has since been modernised by Otis in the early 2000s, however it still retains its original positioning system on the cartop.
At the top and bottom of the shaft are ramps which the roller runs across to alternate which switches are active.
Originally, the entire shaft would have been set with these ramps in a ‘ZigZag’ layout.
The cartop positioning system would work in sync with the floor selector in the machine room to accurately slow down and level the lift into the floor.
After the modernisation, it now only functions as a sort of limit switch. Only one of the contacts are wired in, and it only operates at terminal floors.
Here is the original machinery in action:
ua-cam.com/video/w0Jy805xYJE/v-deo.htmlsi=QlV4K-z_OJsU9cWi
ua-cam.com/video/hz7NvgZaoDM/v-deo.htmlsi=cAP9etFaP6ME09SV
Thanks for showing the positioning system close up very interesting!
What a brilliant video, kind of reminds me of playing Minecraft, steam and rails 🤔😉
That is only the slowdown box for terminal slowing, the variable transformer on the end reduces voltage to the regulator, the floor levelling system was a well transducer that was switched over from contact 7 on the up down selector panel, as the tapered plate entered the transducer the propertional value due to the plate blocking the AC from to the receiver was fed into the regulator, when both transducers were on the plate evenly the value was reduced to zero, this had a PHL light sensor that shone through a hole in the middle of the plate for door zone confirmation and final stopping, this allowed the drive to run in an S curve to the floor but always overshot slightly and levelled back (this was normal). Much faster than most modern lifts when it was set up correctly. I will see if I can find a picture of a well transducer for you
@@liftguy30 Wow, that’s a lot of design effort just for it to only work at terminal floors!
Really interesting to hear about the well transducer. I do remember being told about it some time back.
So, the the theory of the ramps in the shaft being set up in a Zig-Zag layout is incorrect, and the only ramps that would’ve ever been there is just at the top and bottom?
It would be great to see what the well transducer looked like! Please do let me know if you manage to find the photo!
I have found a manual, some selsyn generators and motors and a silverstat damping switch, I’ll do a video when time permits
Polish medium and high-speed lifts (Ward-Leonard drive) make use of actually a similar design but only as limit switches, there are few positions which introduce speed limits as car approaches end of shaft.
But here it looks like a more sophiscated device. What is the purpose of this variable air-gap/coupling transformer at the front of this device? It suggests some analog feedback of the car position.
To be honest, I couldn’t really say 😅
But I’d refer to LiftGuy30’s comment above as he is in the know about it
Even though it has been modernised, that's an amazing find for sure!
Wow!
It's a shame nobody ever filmed the last set of DMR lifts at that civic centre before it closed...
@@LucasTheTechCollector Absolutely! It wasn’t even that long ago. Have you seen the couple of photos of the machine room which exist?
@@Lift.Tracker No, I don't think I have! Had they been modernised in any way or were they 100% original?
@@LucasTheTechCollector They were original, however Express had begun refurbishing them in the mid 1990s with an electronic despatcher known as the QDOS Overlay System.
So all the old controllers are there, but there’s another new Express cabinet to the side with PCBs and a monitor in it handling the calls.
Elevonic 411M? I know of a set of 2 Elevonic 411s that had this exact mechanism as well. Those were fresh installs in the 90s and weren't mods from older lifts
@@LiftyGamez It was the EXACT same? Or just a similar design? That’s really interesting because Elevonic 411 is a microprocessor based controller isn’t it?
Also, do you know what other sort of positioning system the Elevonic has as well, or is it just that on its own?
Just trying to think why it would need something so complex like that, as I’ve been told that this device is actually only for the terminal floor stopping, and not used as a general positioning. I’m still yet to correct the title and think of what to say lol
@@Lift.Tracker I couldn't see the inside as the box was jammed shut, but when the lifts were still in service it had the exact same design with the long ramps at the top and bottommost floors and the switch on the box. Those had selector tape for positioning too which I thought was a bit odd
@@LiftyGamez Yeah, that does seem odd. Given that Elevonic 411 is microprocessor based, why would it have selector tape as if it has a pie plate selector the same as a relay Otis? Maybe it actually did have a pie plate selector and had a controller like a sort of microprocessor version of this? ua-cam.com/video/RXeF6ZSUbCc/v-deo.htmlsi=OfowVKdRoqc6n9vR
I really don’t know much about Otis stuff to be honest. There’s a lot more variety compared to other manufacturers with Otis I think!
@@Lift.Tracker no, as far as I can tell the selector tape probably drives an encoder of sorts, which sends feedback to the controller. I know of 90s Japanese made Otis lifts that have this positioning system as well as some 401s, but never expected it to be used on a 411. Other 401s and 411s use the standard shaft bars without any selector tape, but its hard to tell which positioning system an Elevonic uses without looking into the shaft or motor room