The OMT is the medium-duty ceiling trolley: 1/2 HP on a standard 120V circuit, driving a carriage along a track rather than turning a torsion shaft. It suits smaller industrial standard lift sectional doors that do not cycle much.
What This Operator Suits
Smaller, low-cycling industrial standard lift sectional doors.
A trolley is the answer when there is no torsion shaft to drive, or when the door is a standard lift and a ceiling mount is simply easier. Dual 12-gauge pre-drilled galvanized tracks come standard for doors up to 12 ft in height, with additional track lengths available.
The motor is intermittent-duty with high starting torque, built to start a door decisively and then rest. That is the correct choice for a door opened a handful of times a day and the wrong one for a door running constantly, which is what the apartment-series trolleys exist for.
Specification
| Item | Detail |
|---|---|
| Motor | 1/2 HP, 120V single-phase, intermittent-duty, open type with instant reverse and internal automatic reset thermal overload protection (60Hz). Removable without affecting limit switch settings |
| Reduction | 4L/A V-belt first step, additional step by #48 (#410) chain and sprockets. 5/8″ input, 1″ output shaft, ball bearings |
| Drive and trolley | #48 (#410) full roller chain. Dual 12-gauge pre-drilled galvanized tracks for doors up to 12 ft height standard |
| Brake | Optional electrically activated drum-band solenoid brake, consult inside sales |
| Manual operation | Quick release disconnect arm |
Duty rating in plain terms. Medium duty, intermittent. Note this is an intermittent-duty motor, cycle frequency is the constraint, not door size alone.
What Fails on This Unit
Intermittent-duty motors overheat when a building starts using the door far more than it was specified for. Thermal overload trips, the door stops mid-shift, it cools and works again, and everyone calls it intermittent. That pattern usually means the operator is under-specified for how the door is now being used, not that it is broken.
On the mechanical side it is trolley track and chain wear. A track out of alignment binds the carriage and loads the motor.
Manufacturer Documents
Originals from Manaras-Opera, useful if the paperwork for a unit already in your building has gone missing:
Choosing Between Models
The OTH is the heavy-duty continuous-duty trolley for higher cycle counts. If you are unsure which unit you have, the model code is on the data plate on the operator housing. Note the voltage and phase while you are there, and roughly how many cycles a day the door runs, those three facts decide most of what we would bring to a call.
See the full Manaras model reference for the whole range, or Manaras operator repair for service.
Parts and Accessories
Manaras publish a full accessory range that pairs with this operator: monitored and non-monitored photoelectric cells, light curtains, electric and pneumatic sensing edges, interface modules, push-button and key switch control stations, pull switches, keypads and card readers, radio receivers and transmitters, and traffic light kits.
One point that causes repeated confusion: on a UL 325 monitored circuit, a failed safety device makes the operator refuse to close. That is correct behaviour, not a malfunction. A door that suddenly will not close, with no other symptom, is very often a photo eye or sensing edge that has failed or drifted out of alignment.
- Accessory catalogue (PDF)
- Accessories and replacement components list (PDF)
- Radio Series 900 dip-switch compatibility chart (PDF)
- Radio Series 100 rolling code compatibility chart (PDF)
- Operator codes explained (PDF)
We stock the common wear items for the Opera and MEGA series, control boards, clutches, solenoid coils, limit switch assemblies and safety edges. Anything we do not carry we source through our distributor, and you will hear about a lead time before we attend rather than after.
Frequently Asked Questions
How do I confirm I have a OMT?
The model code is on the data plate on the operator housing. If the plate is unreadable, which happens on older units in damp parkades, send us a photo of the operator and we can usually identify it from the frame and drive layout.
Do you stock parts for it?
We carry the common wear parts across the Opera and MEGA series. Model-specific components come through our distributor, typically within two business days.
Is it worth repairing or should we replace it?
Clutches, brakes, boards, limits, safety devices and wiring are repairs. A seized gear reducer or a burnt-out motor on a very old unit is usually a replacement. We tell you which one you are looking at and why, rather than leading with a new-operator quote.
Can you service a unit we did not buy from you?
Yes. Most Manaras units we attend were installed by someone else, often years ago.
The door will not close but opens fine. Is the operator dead?
Almost certainly not. That is the classic monitored safety circuit symptom, a photo eye, light curtain or sensing edge that has failed or moved. Check the lenses are clean, the alignment is good, and nothing is parked in the beam before assuming the worst.