Nice to see the old Borg Warner controller and DC supply system still in use and running, those work well, though are not as energy efficient, and do have a slightly higher cost to maintain. But a new set of brushes, a quick clean of the commutators, and an undercut to clean the slots, and they will keep on running just about forever.
It is an extremely rare sight, especially here in Europe. While it does take more effort to maintain this lift compared to the main group of 3, I think this does level out as the service lift gets a lot less use than the main lifts. If looked after correctly, this truly is a piece of engineering that lasts.
Wow Wow Wow! I have only one word for your video of this lift, that's Wow! It's my favorite technique of lifts, by far it is, and so much more technique compared to modern lifts. I worked for a year in a hotel, 20 floors, with 4 lifts in one group. My work included accompanying the lifts service engineers who came regurlary for maintenance. Entering the motor room you felt that it was 'alive': a lot of electrical sparks and (of course) a lot of clicking of the relays and switches going on, and the running of the Ward-Leonhards. Sometimes I went up there just to listen to the sound, standing with my back to the entrance door, lights out, enjoying the electrical sparks too. Also I particularly mention the call dispatch cabinet we had there who on a call for a lift made the decision which lift went to what floor. Another thing which makes a difference with modern lifts: the traction motor looks so tiny on here, it's almost the smallest item in the room, as it is surrounded with all the big cabinets of relays and switces. And there is the pie plate cabinet of course, my fascination for this kind of technique has no limits, still not. Modern lift motor rooms: the motor is the biggest item in the room, as the cabinet is just hanging on a wall, with all the necessary equipment to run the lift in it, that's all. Thank you again for your work, seeing this is a big WOW! from me to you. Thank you for reading all of this, it's was lot to read I know, but I go quite emotional when I see the video, Simon
Thank you for your words, I'm glad you like the video! Indeed, these old lifts truly feel alive and have character! There's a lot going on in the motor room and it's also still fascinating to me to see all the machinery work. I find it very impressive how the engineers from 50 years ago have come up with these elaborate electro-mechanical solutions. Nowadays we would just solve anything through programming and there is just no more character and excitement in that compared to all the moving parts of the old way of doing things. On some occasions I actually feel sad when visiting some of these older lifts. Many of them run extremely nice and are satisfying to watch. But in the back of my mind I know that some day they will be modernised or replaced and whatever is about to come will never match the old state. This is my motivation to document what is and to keep it alive online for others to see.
Was hoping to see that governor go balls out...😅 This is the coolest elevator I've ever seen. The way the logic is mechanically working is mind numbing. They electrical smell in that room I bet is incredible! Thanks for the tour! Awesome stuff!
I'm glad you like it! Indeed, this is a marvel of engineering and an absolute rarity. I too love just watching this machinery work, it's truly beautiful.
HO WOW look at this. It's absolutely fascinating, I love the old OTIS elevators with original, totally American relays and what's more, the Otis vertical rotary selector is really incredible, and also the famous AC/DC converter. I LIKE THIS! A technology that is now a thing of the past but so stylish and fast in the past, a real beauty!
Indeed, it is an absolutely beautiful lift. Especially the selector is so nice to look at, a marvel of engineering. I also love the relays cycling through the different speeds when starting and stopping, it just all sounds so nice.
Schachtfahrt bei Normalbetrieb? Klar, aber nur für RUclips! Das Kopierwerk ist der Hammer. Im Vergleich zu heutigen digitalen Systemen eine konstruktive Meisterleistung.
Natürlich, nur für die Aufnahme. Eine solche Anlage sieht man ja auch nicht alle Tage. Die alten Kopierwerke aus den 60er und 70er Jahren sind echte elektromechanische Meisterwerke. Gerade dass Otis hier mit dem Motor auf dem Schlitten ein Modell des Bremsweges aufbaut ist absolut faszinierend.
Another great video, without narration, clean audio...Love the keytag ( call initiiator). Hoistway video is outstanding. There's just something about the 6850 selector, a gearless machine and 2:1 roping.
Absolut, danke dir. Hätte ich aber ohne meine Kontakte in NRW auch nie filmen können. Ich denke, da es sich hier um den Service-Aufzug handelt, hat man eine modernisierung aus Kostengründen einfach nicht für nötig gehalten. Das macht ja grundsätzlich auch Sinn, denn damit fahren die Bewohner ja normalerweise nicht. Ausser für einen Umzug villeicht / grössere Warentransporte.
Der Antriebsmotor sieht irgendwie nach Reihenschlussmotor, und nicht nach Gleichstrommotor aus. Oder werden hier einfach Elektromagnete statt Permanentmagnete verwendet?
Reihenschlussverhalten wäre aufgrund des stark drehzahlabhängigen Drehmoments für Aufzüge gänzlich ungeeignet, sie fanden/finden nur bei älteren Lokomotiven Anwendung. Hier wird ein Nebenschlussmotor mit hoher Drehzahlsteifigkeit verwendet bei dem die Drehzahl proportional zur Ankerspannung ist, die Gleichspannung wird über den rotierenden Umformer erzeugt und die Fahrkurve über Stufen der Schachtkopierung realisiert, durch die mechanische Trägheit erfolgt ein gefühlt stufenloses Verzögern/Anfahren. Solche Umwege waren damals notwendig weil Asynchronmaschinen nur polumschaltbar "schnell - langsam" betrieben werden konnten, ungeeignet für schnellere Anlagen. Ab den 80ern kamen Phasenanschnittsteuerungen hinzu mit denen Drehstrommaschinen drehzahlregelbar waren, teilweise in Kombination mit einer Gleichstrombremsung, Wirkungsgrad und Geräuschverhalten sind dabei suboptimal, aber immerhin entfällt der Nachteil der Gleichstromtechnik (Umformer, Kohlenabrieb). Ab Mitte der 90er wurden die Umrichter im Vierquadrantenbetrieb langsam preislich besser und auch zuverlässiger, waren aber auch kein Ohrenschmaus. Erst ab Mitter der 00er würde ich das Zusammenspiel Motor-Umrichter als perfekt bezeichnen, es hat dazu 100 Jahre gebraucht - ähnlich Lange wie der moderne Verbrennungsmotor im Auto auch gebraucht hat.
@@MultiThibor Danke für die Erläuterungen, das ist höchst interessant. Demfall hat Otis hier einen anderen, weit simpleren Ansatz gewählt als Schindler bei ihrem Ward-Leonhard Antrieb Transitronic. Dort sind Hubmotor und Generator jeweils fremderregte Maschinen und die Ankerwicklungen sind fix miteinander verbunden, ohne Schütze dazwischen. Die komplette Antriebsregelung geschieht über die Erregerspannungen, welche auf Thyristor-Prints im Antriebsregelgerät EGWL generiert werden. Das hat natürlich den Vorteil, dass keine Widerstände zur Geschwindigkeitsregulierung benötigt werden. Die älteren Versionen dieses Antriebs nutzten eine analoge Sollwertgenerierung, während bei der letzten, bis in die 90er Jahre eingesetzten Version mit Microprozessor, die Sollwerte für die Spannungen elektronisch generiert wurden. Dieses System war die Königsklasse des DC-Antriebs und beherrschte perfekte Direkteinfahrt von 6.3m/s bis zum Stillstand, vollständig wegabhängig geregelt. Das steht im Punkto Fahrkomfort einem heutigen Frequenzumrichter praktisch in nichts nach und war damals definitiv seiner Zeit voraus. Leider gibt es nur noch eine Handvoll solcher Anlagen.
@@TheLiftDragon Die Schweizer sind in allem wahre Meister der Perfektion, vieles wird bis zum Letzten durchoptimiert, die Preise sind aber auch dementsprechend hoch und die Wettbewerbsfähigkeit von manchen Dingen ist dann fraglich. Aus dem Grund wurde die BBC in den 80ern auch vom schwedischen ASEA Konzern übernommen und zur ABB fusioniert, dabei wurde viel "Schnörkel" entfernt. Ich denke nicht, dass das System in den USA neben OTIS Bestand hätte, Strom ist billiger und thyristorbasierte Analogregler sind so ziemlich die kompliziertesten Schaltungen die es damals gab, Siemens hatte nie Glück mit ihren Analogprodukten, mit Einführung von Digitaltechnik wanderte viele sofort auf den Schrott, die Fehlersuche war oft teurer als ein Austausch. AEG-Telefunken ging mit ihrem Analog-ABS welches an Citroen verkauft werden sollte ebenfalls Baden, Mercedes lehnte es gänzlich ab wegen Zuverlässigkeitsproblemen und fehlender Eigendiagnosefähigkeit.
Wow. Ich nehme mal an, dass ist die Anlage, die bereits in zwei anderen Videos vorkam - richtig? Es gab schon die Befürchtung, dass diese nicht mehr existiert.
Genau, diese Anlage wurde auf RUclips auch schon gezeigt. So wie ichvernommen habe, soll der Servicelift auch noch länger so bleiben. Die Haupt-3er-Gruppe wurde ja schon Ende 90er umgebaut mit 18ATF maschinen. Ich muss an der Stelle aber uch anmerken, dass die Aufnahmen hier noch aus letztem Jahr stammen und daher nicht genau den heutigen Zustand zeigen.
That's a very unique gearless motor right there! I did see another video with vintage Otises using this motor too, but apparently those were destroyed in an earthquake. Is this some 'baby gearless' motor for low capacity, high speed lifts?
Indeed, I have yet not seen this type of motor on any other install. 600kg is a very small capacity for such a fast lift and I think these motors were only used in such rare scenarios where high speed for rather low capacity was needed. I don't know what motors the other 3 lifts originally had as they're now 18ATF. What I find especially confusing is the following: Traction sheaves with trapezoidal grooves don't need double wrapping because of higher friction while sheaves with round grooves need double wrapping. High-speed gearless machines generally have round grooves, like this one here. That's why there's 8 grooves on the traction- and deflecting sheaves for double wrap. BUT: The 18 ATF machines (these have trapezoidal grooves) sit on the original motor frames and these deflecting sheaves only have 4 grooves instead of the needed 8 for a gearless machine, so this raises the question what was there before the 18ATF? I can't really imagine that the deflecting sheaves have been changed with the new machines as they look the same as the one of the original lift. Also these 3 lifts have a slightly higher capacity of 750kg.
@@TheLiftDragon normally Otis gearless machines for 2.5m/s only have single wrap, I've seen videos of regular gearless machines from Otis and other brands using only a single wrap, but of course these are for standard sized lifts. I'm guessing the diameter of this small gearless machine didn't allow trapezoidal grooves to be used, or perhaps the light capacity and how light the lift car and counterweight components look didn't provide enough traction?
@@LiftyGamez Hmm, yes, now after you've mentioned it: I know a large set of 2.5m/s DC Otises that also have trapezoidal grooves and are single-wrap. They have the larger 131HT machines. I really think it depends on the machine type. Nominal speed of this machine is 239 rpm, which exactly results in a sheave diameter of 400mm. That's not too small in my opinion, it's pretty common on many newer machines. Also the ropes are pretty small in diameter, making it easier for them to bend around the radius. The weight of the car should also not be that much of a problem because the capacity of the lift is small. The lift is actually pretty big for it's small capacity, so the weight of the car and CW should generate enough grip. It's really weird.
I *really* don't understand this selector, and especially the role of the little motor that is part of it. This combination of design elements surprises me, because I thought gearless drive was super-modern and control with relays super-old. Has anyone built a lift that used a constant-speed motor, like the motor-generator here, but that coupled it to the winding sheave by other means than electrical? It cold be hydraulic, pneumatic, or with clutches and a gearbox.
I have to admit that I have not yet fully studied the device either. I am very familiar with all that Schindler and Schlieren have produced and I also have all the Schematics for these. But I never fully got into studying old Otis installs as they are extremely rare in my area. The small motor in the selector advances the carriage in the direction of travel upon starting, which is necessary because the braking distance is bigger than the floor distance. Also mentioned in the description. Gearless drives for lifts are absolutely nothing new, they have existed for over 100 years. They are the only way of driving a high-speed lift. The speed of this lift here, 2.5m/s, is approximately the fastest speed that can be achieved with geared machines (see the geared 18ATF machines in the background). I would not be surprised if that number was lower 100 years ago. To name an example: the Woolworth building in New York, completed in 1912 and once the tallest building in the world, had lifts travelling at 3.5m/s. These units must have used gearless machines to achieve said speeds. However, what is indeed new is the use of gearless machines in slow low-rise applications. This had not been possible prior to the 1990s because back then, gearless machines were always DC. They had to be DC because there were no VVVF drives and therefore no means of speed controlling a synchronous 3 phase machine, which almost all gearless machines are. The DC control equipment is much more complex than the 4 contactors needed for a 2-speed asynchronous geared machine, therefore this option was never feasible for areas where a geared machine would suffice. I don't know whether such exotic controls have ever existed but I would not be surprised if they did. I surely could imagine that a clutch was a good solution back in the day, for example in a factory with permanently running steam engines.
That motor on the selector runs the advancer panel. That controls the acceleration/deceleration of the machine. The advancer panel extends ahead of the main selector cross head (upwards or downwards). The amount that it extends controls the speed. A call that requires a stop will energise a contact on a floor bar. When the panel reaches that, a latch is engaged and it is held while the main cross head catches up. This runs the contact bar that slows the machine down again. I worked with these, installation, set-up and later maintenance, over a period of 40+ years, yet they were always fascinating to watch in action.
But I full lift, great video too, nowerdays its quite rare to find a Relay lift on a highrise building, also, I love Otis DC Genrator lifts and pie-plate selector, does this lift have 3 speeds? It is gearless if I am not wrong. (I am the first commenter)
6:13 What is that plate at the bottom as well as that small round black thing at the far right (looks like a motor or encoder, but what would an encoder be doing in a relay based elevator) later we can also see a motor-like thing, what is that and what does it do (it’s @ 6:16)?
That belongs to the set of main lifts which is mentioned in the video description. Please consider reading it as the answers to many questions can be found there. I usually put a lot of extra information in the description.
The plate is for exact indication of the lifts position so that the levelling position can be readjusted. That's what the markings are for. The encoder on the side actually is an encoder, it is an add-on for overspeed monitoring and it would interrupt the safety circuit if the lift got too fast, before the actual governor trips. The motor on the selector carriage advances part of the contacts, which is needed because of the long braking distance due to the high speed. also mentioned in description.
Einen solchen Motorraum und solche mechanische Anlage habe ich noch nie gesehen. gute Aufnahme
Dankesehr. Ja, das hier ist wirklich eine äusserst faszinierende Anlage.
I do love the vintage machinery.
Me too!
Nice to see the old Borg Warner controller and DC supply system still in use and running, those work well, though are not as energy efficient, and do have a slightly higher cost to maintain. But a new set of brushes, a quick clean of the commutators, and an undercut to clean the slots, and they will keep on running just about forever.
It is an extremely rare sight, especially here in Europe. While it does take more effort to maintain this lift compared to the main group of 3, I think this does level out as the service lift gets a lot less use than the main lifts. If looked after correctly, this truly is a piece of engineering that lasts.
Wunderschöne Anlage. Schön diese alte Mechanik noch zu sehen
So ist es. Leider sehr selten geworden heute.
Wow Wow Wow! I have only one word for your video of this lift, that's Wow! It's my favorite technique of lifts, by far it is, and so much more technique compared to modern lifts.
I worked for a year in a hotel, 20 floors, with 4 lifts in one group.
My work included accompanying the lifts service engineers who came regurlary for maintenance. Entering the motor room you felt that it was 'alive': a lot of electrical sparks and (of course) a lot of clicking of the relays and switches going on, and the running of the Ward-Leonhards.
Sometimes I went up there just to listen to the sound, standing with my back to the entrance door, lights out, enjoying the electrical sparks too.
Also I particularly mention the call dispatch cabinet we had there who on a call for a lift made the decision which lift went to what floor.
Another thing which makes a difference with modern lifts: the traction motor looks so tiny on here, it's almost the smallest item in the room, as it is surrounded with all the big cabinets of relays and switces. And there is the pie plate cabinet of course, my fascination for this kind of technique has no limits, still not.
Modern lift motor rooms: the motor is the biggest item in the room, as the cabinet is just hanging on a wall, with all the necessary equipment to run the lift in it, that's all.
Thank you again for your work, seeing this is a big WOW! from me to you.
Thank you for reading all of this, it's was lot to read I know, but I go quite emotional when I see the video, Simon
Thank you for your words, I'm glad you like the video!
Indeed, these old lifts truly feel alive and have character! There's a lot going on in the motor room and it's also still fascinating to me to see all the machinery work. I find it very impressive how the engineers from 50 years ago have come up with these elaborate electro-mechanical solutions. Nowadays we would just solve anything through programming and there is just no more character and excitement in that compared to all the moving parts of the old way of doing things.
On some occasions I actually feel sad when visiting some of these older lifts. Many of them run extremely nice and are satisfying to watch. But in the back of my mind I know that some day they will be modernised or replaced and whatever is about to come will never match the old state. This is my motivation to document what is and to keep it alive online for others to see.
Was hoping to see that governor go balls out...😅 This is the coolest elevator I've ever seen. The way the logic is mechanically working is mind numbing. They electrical smell in that room I bet is incredible! Thanks for the tour! Awesome stuff!
I'm glad you like it! Indeed, this is a marvel of engineering and an absolute rarity. I too love just watching this machinery work, it's truly beautiful.
Such a beautiful electromechanical machine, even has predoors!
It absolutely is! Thx.
epic motor and relays sound
Indeed, thx!
HO WOW look at this. It's absolutely fascinating, I love the old OTIS elevators with original, totally American relays and what's more, the Otis vertical rotary selector is really incredible, and also the famous AC/DC converter. I LIKE THIS!
A technology that is now a thing of the past but so stylish and fast in the past, a real beauty!
Indeed, it is an absolutely beautiful lift. Especially the selector is so nice to look at, a marvel of engineering. I also love the relays cycling through the different speeds when starting and stopping, it just all sounds so nice.
Those doors sound EXACTLY like the 60's black button Otis I found awhile back, it's surreal haha.
Haha, nice. So I guess it's the same equipment then, would make sense.
Schachtfahrt bei Normalbetrieb? Klar, aber nur für RUclips! Das Kopierwerk ist der Hammer. Im Vergleich zu heutigen digitalen Systemen eine konstruktive Meisterleistung.
Natürlich, nur für die Aufnahme. Eine solche Anlage sieht man ja auch nicht alle Tage. Die alten Kopierwerke aus den 60er und 70er Jahren sind echte elektromechanische Meisterwerke. Gerade dass Otis hier mit dem Motor auf dem Schlitten ein Modell des Bremsweges aufbaut ist absolut faszinierend.
Another great video, without narration, clean audio...Love the keytag ( call initiiator). Hoistway video is outstanding. There's just something about the 6850 selector, a gearless machine and 2:1 roping.
Thx, I'm glad you like my work!
This has also become a really rare installation and just a perfect combination of equipment.
Wahnsins Anlage 😮, ein sehr guter Fund 😉.
Währe Interessant zu wissen warum genau dieser Aufzug nicht Modernisiert wurde.
Absolut, danke dir. Hätte ich aber ohne meine Kontakte in NRW auch nie filmen können.
Ich denke, da es sich hier um den Service-Aufzug handelt, hat man eine modernisierung aus Kostengründen einfach nicht für nötig gehalten. Das macht ja grundsätzlich auch Sinn, denn damit fahren die Bewohner ja normalerweise nicht. Ausser für einen Umzug villeicht / grössere Warentransporte.
Der Antriebsmotor sieht irgendwie nach Reihenschlussmotor, und nicht nach Gleichstrommotor aus. Oder werden hier einfach Elektromagnete statt Permanentmagnete verwendet?
DC-Maschinen für Ward-Leonhard-Abtrieb sind grubdsätzlich fremderregte Gleichstrommaschinen, wo also die Erregerwicklung separat gespeist wird.
Reihenschlussverhalten wäre aufgrund des stark drehzahlabhängigen Drehmoments für Aufzüge gänzlich ungeeignet, sie fanden/finden nur bei älteren Lokomotiven Anwendung.
Hier wird ein Nebenschlussmotor mit hoher Drehzahlsteifigkeit verwendet bei dem die Drehzahl proportional zur Ankerspannung ist, die Gleichspannung wird über den rotierenden Umformer erzeugt und die Fahrkurve über Stufen der Schachtkopierung realisiert, durch die mechanische Trägheit erfolgt ein gefühlt stufenloses Verzögern/Anfahren.
Solche Umwege waren damals notwendig weil Asynchronmaschinen nur polumschaltbar "schnell - langsam" betrieben werden konnten, ungeeignet für schnellere Anlagen.
Ab den 80ern kamen Phasenanschnittsteuerungen hinzu mit denen Drehstrommaschinen drehzahlregelbar waren, teilweise in Kombination mit einer Gleichstrombremsung, Wirkungsgrad und Geräuschverhalten sind dabei suboptimal, aber immerhin entfällt der Nachteil der Gleichstromtechnik (Umformer, Kohlenabrieb).
Ab Mitte der 90er wurden die Umrichter im Vierquadrantenbetrieb langsam preislich besser und auch zuverlässiger, waren aber auch kein Ohrenschmaus.
Erst ab Mitter der 00er würde ich das Zusammenspiel Motor-Umrichter als perfekt bezeichnen, es hat dazu 100 Jahre gebraucht - ähnlich Lange wie der moderne Verbrennungsmotor im Auto auch gebraucht hat.
@@MultiThibor Danke für die Erläuterungen, das ist höchst interessant. Demfall hat Otis hier einen anderen, weit simpleren Ansatz gewählt als Schindler bei ihrem Ward-Leonhard Antrieb Transitronic. Dort sind Hubmotor und Generator jeweils fremderregte Maschinen und die Ankerwicklungen sind fix miteinander verbunden, ohne Schütze dazwischen. Die komplette Antriebsregelung geschieht über die Erregerspannungen, welche auf Thyristor-Prints im Antriebsregelgerät EGWL generiert werden. Das hat natürlich den Vorteil, dass keine Widerstände zur Geschwindigkeitsregulierung benötigt werden. Die älteren Versionen dieses Antriebs nutzten eine analoge Sollwertgenerierung, während bei der letzten, bis in die 90er Jahre eingesetzten Version mit Microprozessor, die Sollwerte für die Spannungen elektronisch generiert wurden. Dieses System war die Königsklasse des DC-Antriebs und beherrschte perfekte Direkteinfahrt von 6.3m/s bis zum Stillstand, vollständig wegabhängig geregelt. Das steht im Punkto Fahrkomfort einem heutigen Frequenzumrichter praktisch in nichts nach und war damals definitiv seiner Zeit voraus. Leider gibt es nur noch eine Handvoll solcher Anlagen.
@@TheLiftDragon
Die Schweizer sind in allem wahre Meister der Perfektion, vieles wird bis zum Letzten durchoptimiert, die Preise sind aber auch dementsprechend hoch und die Wettbewerbsfähigkeit von manchen Dingen ist dann fraglich.
Aus dem Grund wurde die BBC in den 80ern auch vom schwedischen ASEA Konzern übernommen und zur ABB fusioniert, dabei wurde viel "Schnörkel" entfernt.
Ich denke nicht, dass das System in den USA neben OTIS Bestand hätte, Strom ist billiger und thyristorbasierte Analogregler sind so ziemlich die kompliziertesten Schaltungen die es damals gab, Siemens hatte nie Glück mit ihren Analogprodukten, mit Einführung von Digitaltechnik wanderte viele sofort auf den Schrott, die Fehlersuche war oft teurer als ein Austausch.
AEG-Telefunken ging mit ihrem Analog-ABS welches an Citroen verkauft werden sollte ebenfalls Baden, Mercedes lehnte es gänzlich ab wegen Zuverlässigkeitsproblemen und fehlender Eigendiagnosefähigkeit.
Wow. Ich nehme mal an, dass ist die Anlage, die bereits in zwei anderen Videos vorkam - richtig? Es gab schon die Befürchtung, dass diese nicht mehr existiert.
Yes these lifts are getting very rare.
Genau, diese Anlage wurde auf RUclips auch schon gezeigt. So wie ichvernommen habe, soll der Servicelift auch noch länger so bleiben. Die Haupt-3er-Gruppe wurde ja schon Ende 90er umgebaut mit 18ATF maschinen.
Ich muss an der Stelle aber uch anmerken, dass die Aufnahmen hier noch aus letztem Jahr stammen und daher nicht genau den heutigen Zustand zeigen.
That's a very unique gearless motor right there! I did see another video with vintage Otises using this motor too, but apparently those were destroyed in an earthquake. Is this some 'baby gearless' motor for low capacity, high speed lifts?
Indeed, I have yet not seen this type of motor on any other install. 600kg is a very small capacity for such a fast lift and I think these motors were only used in such rare scenarios where high speed for rather low capacity was needed. I don't know what motors the other 3 lifts originally had as they're now 18ATF. What I find especially confusing is the following: Traction sheaves with trapezoidal grooves don't need double wrapping because of higher friction while sheaves with round grooves need double wrapping. High-speed gearless machines generally have round grooves, like this one here. That's why there's 8 grooves on the traction- and deflecting sheaves for double wrap. BUT: The 18 ATF machines (these have trapezoidal grooves) sit on the original motor frames and these deflecting sheaves only have 4 grooves instead of the needed 8 for a gearless machine, so this raises the question what was there before the 18ATF? I can't really imagine that the deflecting sheaves have been changed with the new machines as they look the same as the one of the original lift. Also these 3 lifts have a slightly higher capacity of 750kg.
@@TheLiftDragon normally Otis gearless machines for 2.5m/s only have single wrap, I've seen videos of regular gearless machines from Otis and other brands using only a single wrap, but of course these are for standard sized lifts. I'm guessing the diameter of this small gearless machine didn't allow trapezoidal grooves to be used, or perhaps the light capacity and how light the lift car and counterweight components look didn't provide enough traction?
@@LiftyGamez Hmm, yes, now after you've mentioned it: I know a large set of 2.5m/s DC Otises that also have trapezoidal grooves and are single-wrap. They have the larger 131HT machines. I really think it depends on the machine type. Nominal speed of this machine is 239 rpm, which exactly results in a sheave diameter of 400mm. That's not too small in my opinion, it's pretty common on many newer machines. Also the ropes are pretty small in diameter, making it easier for them to bend around the radius.
The weight of the car should also not be that much of a problem because the capacity of the lift is small. The lift is actually pretty big for it's small capacity, so the weight of the car and CW should generate enough grip. It's really weird.
I *really* don't understand this selector, and especially the role of the little motor that is part of it.
This combination of design elements surprises me, because I thought gearless drive was super-modern and control with relays super-old.
Has anyone built a lift that used a constant-speed motor, like the motor-generator here, but that coupled it to the winding sheave by other means than electrical? It cold be hydraulic, pneumatic, or with clutches and a gearbox.
I have to admit that I have not yet fully studied the device either. I am very familiar with all that Schindler and Schlieren have produced and I also have all the Schematics for these. But I never fully got into studying old Otis installs as they are extremely rare in my area.
The small motor in the selector advances the carriage in the direction of travel upon starting, which is necessary because the braking distance is bigger than the floor distance. Also mentioned in the description.
Gearless drives for lifts are absolutely nothing new, they have existed for over 100 years. They are the only way of driving a high-speed lift. The speed of this lift here, 2.5m/s, is approximately the fastest speed that can be achieved with geared machines (see the geared 18ATF machines in the background). I would not be surprised if that number was lower 100 years ago. To name an example: the Woolworth building in New York, completed in 1912 and once the tallest building in the world, had lifts travelling at 3.5m/s. These units must have used gearless machines to achieve said speeds.
However, what is indeed new is the use of gearless machines in slow low-rise applications. This had not been possible prior to the 1990s because back then, gearless machines were always DC. They had to be DC because there were no VVVF drives and therefore no means of speed controlling a synchronous 3 phase machine, which almost all gearless machines are. The DC control equipment is much more complex than the 4 contactors needed for a 2-speed asynchronous geared machine, therefore this option was never feasible for areas where a geared machine would suffice.
I don't know whether such exotic controls have ever existed but I would not be surprised if they did. I surely could imagine that a clutch was a good solution back in the day, for example in a factory with permanently running steam engines.
@@TheLiftDragon Thanks.
That motor on the selector runs the advancer panel. That controls the acceleration/deceleration of the machine. The advancer panel extends ahead of the main selector cross head (upwards or downwards). The amount that it extends controls the speed. A call that requires a stop will energise a contact on a floor bar. When the panel reaches that, a latch is engaged and it is held while the main cross head catches up. This runs the contact bar that slows the machine down again.
I worked with these, installation, set-up and later maintenance, over a period of 40+ years, yet they were always fascinating to watch in action.
But I full lift, great video too, nowerdays its quite rare to find a Relay lift on a highrise building, also, I love Otis DC Genrator lifts and pie-plate selector, does this lift have 3 speeds? It is gearless if I am not wrong. (I am the first commenter)
What is that geared machine In the back? 4:25
6:13 What is that plate at the bottom as well as that small round black thing at the far right (looks like a motor or encoder, but what would an encoder be doing in a relay based elevator) later we can also see a motor-like thing, what is that and what does it do (it’s @ 6:16)?
Thank you.
Indeed, these lifts have become almost fully extinct. And yes it is a gearless of course, as stated in the title.
That belongs to the set of main lifts which is mentioned in the video description. Please consider reading it as the answers to many questions can be found there. I usually put a lot of extra information in the description.
The plate is for exact indication of the lifts position so that the levelling position can be readjusted. That's what the markings are for.
The encoder on the side actually is an encoder, it is an add-on for overspeed monitoring and it would interrupt the safety circuit if the lift got too fast, before the actual governor trips.
The motor on the selector carriage advances part of the contacts, which is needed because of the long braking distance due to the high speed. also mentioned in description.
The another video Is the same 🤯
Yes, I also have a video on the group of 3 main lifts in the same motor room on my channel.