Any advice on what linear door operator to go with on a Montgomery MAC door operator mod/upgrade? I am thinking I need to start getting away from the harmonic operators. I would like to stay with the original MAC door equipment. New hangar rollers, upthrusts, spirators, pickup rollers, lift rods, hooks, interlock contacts, gibs, clutch, ect. My concern is that the clutch dovetail is retracted off the long arm chain. I am kind of leaning toward the Otis Glide operator. We are looking at using the Virginia Controls MH-3000 controller. Any advice/wisdom is much appreciated. Thank you

My advice would be to get the Wittur SGV (AMD model similar). This is the same operator used by Vertical Express (TK), KONE, and Savaria. Both models are now available with an upgrade kit to work on exisiting MAC pickup rollers. The only think you will have to change is the operator, tracks on the cabin side , and the clutch. The operator is fully assembled and is a drop-in replacement. No need to redrill the doors. Just specify MAC adapters. The advantage of the clutch is that it comes with an interlock (not restrictor), eliminating the chances of door misalignment during runs (someone trying to pry doors open during run as a prank, or clipped rollers). to learn more about this product, please see my recent news thread on this same site titled "One size fits all Door operator". Link: http://www.vatortrader.com/forums/ubbthreads.php?ubb=showflat&Number=33378#Post33378

The Otis product is not your best bet in this case. Additional "homemade" hardware will be necessary to accommodate the MAC clutch.

I’m not against the new style linear operators, except that I hate not being able to split the doors. But we just did a door mod on a few old Miproms where the consultant spec’d new Mac operators. I think it’s worth mentioning not only because it was soooo easy to drop in like for like but I really liked the new 105D door board too. It’s closed loop but unlike the shitty 105 board that you needed a tool for, this one has a UIT on it.

To me I'd determine linear or harmonic by what's there already. Like dirt said, it's so much easier replacing like for like. I'm not familiar with the MAC operators, but if they are harmonic I'd look at seeing if a GAL Movfr2 can fit in easily. It would be a perfect complement to the controller your using if it fits mechanically. In my opinion most of the operators now days are so reliable that there's really no drawback to an operator like the MOVFR and being able to split the doors is a huge benefit for service/maintenance. My biggest jobs are a couple 10 story hospitals with 7 to 15 elevators in each one. Over 20 of the cars have been replaced (including new cabs) in the last 5-10 years and could have been spec'd to anything. They could have bought new cabs with linear operators. Every single one of those 20+ cars have a MOVFR on it and gets hundreds of trips/door cycles every day. I almost never have a callback for anything related to the operator.

The MAC operator is a tank compared to an MOVFR II. All the sheaves are on shafts with 2 pillow blocks and big bearings everywhere. The worst thing I can say about them is they aren't exactly a universal fit type operator. They work great on a Montgomery engineered cab but since the throw isn't adjustable there are a lot of mod jobs they were used on where the geometry was never right. I've heard another company makes an adjustable split link for that problem but I've never seen it.

Does the existing system have a door restrictor as part of the Montgomery clutch? If so, you could probably get away with a like-to-like replacement; however, if it doesn't the Wittur products I mentioned above are the best solution.

The main reasons I'm a Grinch of harmonic door operators is as follows:

1. The dangers of the gate switch. They can get inadvertently or intentionally pressed, compromising the safety system. Not all jurisdictions require DLM. Even with DLM, it can still be problematic. The lift could go out of service trapping people on upper floors who can't walk stairs. The new-style linear ones have cabin door interlocks (no gate switch), making such situations impossible. Here's an ex. of what I'm talking about. https://www.youtube.com/watch?v=AEOkZDBCDiw
Being able to spit the door at floor level is also bad. Pranksters are capable of manually separating the doors compromising the lock system. This can also happen if a spring is weak and the door strikes an object.

2. With the presence of interlocks, restrictors are no longer necessary. Harmonic operators do not support cab door interlocks and many types of restrictors can easily be disabled/bypassed by mechanics compromising passenger safety. Worse yet, those electronic restrictors like hatch-latch by Adams can fail in the locked position and are prone to sensor misalignment and dead batteries during power failure. These were responsible for many fatalities at WTC on 9/11. On new installs (especially all glass), no ugly expensive sheet metal is needed between floors.

3. During entrapment, Harmonic operators can become self-locking (operator can move the doors, but doors cannot move operator). This situation requires rescue workers to have to get on the cab top and spin the infamous wheels, this can be problematic in situations where the lift is on the top floor or in the case of a steep drop (i.e train station, garage). Linear door operators never become self-locking. Once interlock is released, door can be manually opened from both floor level and cab top. Also, if lift stalls at floor level, no triangular or drop key is needed due to the spring loaded clutch. All you gotta do is push open the door. See examples below.

Self-locking ex. GAL: https://www.youtube.com/watch?v=9TnHnKU9EnQ
Self-locking ex. MAC (0:36): https://www.youtube.com/watch?v=TcdMfuUJprk
Linear difference: https://www.youtube.com/watch?v=eyjQC7llJkE

4. Use of Harmonic operators on full glass door panels is not only more expensive due to construction costs, but a fall hazard for mechanics. Operators propped up on pedestals pose fall hazards for workers due to a steep drop from the operator to the cab top. New-style linear operators eliminate this.

Thanks for all your advice guys, I appreciate it. I too like to be able to split the doors. I enjoy working on the old Dover/TKE, Montgomery, ESCO cars. I am concerned that the larger companies will begin to obsolete parts for some of the older style door equipment. I am having a hard time getting TKE Vertical Express clutches and some MAC equipment from Spares. Like for like swaps on mods make the jobs cheaper and quicker for the customers.

GAL is the last man standing that's still manufacturing harmonic door operator as a complete item. All others have either stopped them all together, or only make them available as spare parts/limited direct replacement only. No major company uses them on completely new systems that bear their branding.

Most other countries have outlawed the use of harmonic door operators for the reasons I listed above. The US and Canada are the only ones still permitting em.

Just FYI. I checked the KONE spares site. Complete MAC equipment is now rendered obsolete and is no longer sold. Only spare parts and upgrade kits are available. Columbia Elevator Co. does make a knock-off MAC operator. Not sure how it's quality compares to the original Montgomery version.

We just purchased two RH MAC door operators from Spares for our University mod a couple months ago. Very good price at around $1600.00 ea. I hope I didn't get the last ones.

I feel like you're being a bit disingenuous here. You're choosing situations in which the safety systems of the harmonic operator are purposefully defeated/bypassed and comparing them to an unmolested linear operator.

Your first point about pranksters separating doors is largely a non issue and irrelevant. Even in that situation the car wouldn't take off (failsafe) and in a properly adjusted cars both sets of doors would close and put the car back to normal service. Trapping people on upper floors is always a concern with an elevator and I don't see how a linear operator reduces that risk. Also splitting doors definitely aides in maintenance and rescue operations (which the building will care about once they have to pay to fix it).

In your second point you describe a mechanic defeating the purpose of the restrictor/harmonic operator, which I'll admit I have seen in the field, but that's a reflection of the mechanic / service company not the product. You then go on to talk about 9/11 as if the linear operator would have performed any differently in that situation. It wouldn't. If an elevator is outside out of the doorzone you shouldn't be able to open the doors regardless if it's hatchlatch, restrictor, or a linear door lock.

Third point is inaccurate (at least with modern operators). If you can't open the doors by pushing them then something is not adjusted or installed right. GAL has rubber bumpers to prevent the linkages from ever "locking" (and they tell you multiple times in the manual, in bold, not to touch them). MAC uses a split link which allows the door to move independent of the linkages. You say linear door's never become self locking I think what you really mean to say is they require the same force to open at every point of travel ONCE the interlock is picked. If you can't pick that interlock then you'll never get those doors open. A situation I've seen more than once is when the car has a larger lobby entrance which leads to the door operator / door equipment being higher than you can normally reach or otherwise inaccessible on the standard floors.

Having said all that I'll admit now that there are many cases where I feel linear door operator is the better choice. Especially in new construction. But it's not a better choice because of safety or reliability. The GAL product is pretty much the most time tested and widely installed product out there I feel it's record speaks for itself.

In regards to this thread I agree with Indirtwetrust and would probably just drop in a new MAC operator. Especially if you want to reuse equipment and the building doesn't have any ongoing complaints with it.

I agree with LAmech. I don't think it's really that big of a deal, harmonic and linear operators have coexisted for many decades and I think for a few more probably. They both work very well and each have their own advantages. There's a reason GAL sells so many operators. There's still a big demand for them in the independent market where we put in what works best for us/the customer. There's a whole lot of equipment reaching the age for a mod that has harmonic operators coming up. Thinking LRVs, DMCs, etc. Heck the LRVs have GAL operators on them already. I wouldn't dream of going in and modding say an LRV and creating tons of headaches trying to stick a linear operator on it.

As far as none of the big 4 using harmonic operators on their new stuff, I don't believe for a second thats just because linear operators are just the best there is. I believe that is because they're following a bigger market trend.. build cheap cookie cutter elevators that can be built quickly and using as many common parts as possible. By using linear operators they accomplish a couple things. They can use one operator for various door opening sizes and cut cab costs down. And they also don't have to train mechanics in the physics and adjusting harmonic operators. And if your car door is interlocked you also dont have to spend money on fascia or installing fascia. It's all about the money.

FYI, GAL has just came out with an Interlock that can retro fit to their harmonic operators.. no need for fascia...I LOVE THAT PART

The Wittur SGV/AMD (TK ld-16 also related) has a GAL interlock refit (clutch) model. You have to change out the operator, which should be a breeze, because they make mounting adapters. No need to redril mountings on doors. You will see it in the clutches/skates section toward the bottom of this link: https://verticalxpress.com/media/download_files/component_manuals/ld_16_udo_mod.pdf

GAL does make a linear operator w/CDL called MONXT; however unlike the Wittur/KONE.TK product, you can't use the traditional style pickup roller. You have to replace it with new header mounted rollers, which makes it more suited for new installs or GAL/ECI mods requiring pickup roller replacement. I don't know what GAL product Solidstate's describing. Do you have a link?

If you read my earlier post. Facia (sheet metal) is one of the things I don't like about harmonic and old-style linear (Armor, Westinghouse). It's looks tacky on all glass installs. It's also more expensive.