Home Forums General Discussion Technical Questions AT 400

Otis at-400 operator. I’ve got a couple that were put in to replace a sematic operator. There’s a skate on the clutch that opens and closes the clutch. The at400 doesn’t account for the movement of the clutch’s skate. I think I can get everything to work smoothly if I could adjust parameters more than what the software is allowing. Example: stop closing distance , I can only adjust this to 10. The manual I have says the range is 1-100 but it won’t except anything over 10. Is there a way to unlock the ranges of adjustments?

why not just leave the original skate on and be done with it?

The original skate is on it. That’s what the Otis at400 doesn’t like. And I’ve got glass doors with tight clearance , the clutch is at the top of the doors so retrofitting the door clutch, pickups, interlocks,etc will require replacing doors, frames , and probably more. I just want the at400 to work smoothly with the semantic doors if possible.

Can you post some pictures ? Why not do a learn run then move the attachment point over so the door goes full close and lifts the skate? It's not a perfect solution but it'll get you running. Also is it an at400 or a glide?

It’s an AT400. When doing a learn run it goes crazy when it doesn’t get much mechanical resistance when moving the skate to open clutch then starts to actually move door. We’ve tried to lock the skate in place just while doing a learn run but it doesn’t like that either. I’ll take some pics next time I’m there. It’s working now it just doesn’t slow down when closing until right when the doors close. Then it slows down while moving skate.

really need more information and pictures here. if it's 6940 locks and you have a collapsible skate, you need to go to a fixed skate. if this is some other lock/clutch/skate setup, the otis linear operators really don't like them. they can be made to work but have seen lots of issues. this is what happens when sales people don't ask any one in the field. they get their bonus and the customer/mechanic get left pulling their hair out.

I’ve been trying to attach pics but no luck. First time I’ve tried to do that on this forum.

Sematic clutch with skate

To be honest, I would have just stuck with Wittur. They make the Sematic product. A more expensive conversion, but would have worked better than AT-400 would be to buy the Schindler 3300 conversion to MONXT from Vantage. Then remove Sematic equipment (including motor, belt, and idler puly, not the skate though). Then attach the MONXT equipment, including motor, belt, and idler. You may need to make custom mounting plate for motor and idler mounting. The MONXT is just a rebranded version of the Monarch NICE900 modified for the North American market. It will accommodate the collapsible skate. The params are identical to the NICE900/Delta-VFD-DD, just named differently, but the numbers are identical.

To make matters worse, AT-400 is discontinued and only spare are available.

You might be able to just reused your existing belt and pulley with the MONXT product. It's just a regular Monarch motor.

Thanks for the info. Not sure yet what customer is willing to do.