The OGH swaps belt-and-chain reduction for a 45:1 worm gear running in an oil bath. That is a different engineering approach to the same problem: getting high torque to a heavy door at low speed, reliably, for years.
What This Operator Suits
Industrial high and vertical lift sectional doors, rolling doors and grilles.
A worm gear reducer in oil bath with an air breather and sealed ball bearings does not need the belt tension checks a V-belt drive does, and it delivers torque more consistently under sustained load. The trade-off is cost and weight. Where a door is heavy and the building wants long service intervals rather than the lowest install price, this is the sensible specification.
Output shaft is 1″ with a 1/4″ keyway up to 1 HP, stepping to 1-1/4″ above that, worth knowing when matching a replacement to existing drive hardware.
Specification
| Item | Detail |
|---|---|
| Motor | 60Hz high starting torque, continuous-duty, single-phase capacitor start or 3-phase, open drip proof with enclosed ends or drip cover |
| Reduction | 45:1 worm gear in oil bath reducer with air breather and sealed ball bearings |
| Output shaft | 1″ with 1/4″ keyway up to 1 HP; 1-1/4″ with 1/4″ keyway above 1 HP |
| Drive | #50 roller chain with 50B12 sprocket |
| Brake | Electrically activated drum-band solenoid brake |
| Manual operation | Hoist-a-matic self-engaging hoist with automatic cut-off; electrical interlock cuts motor power when engaged |
Duty rating in plain terms. Heavy-duty industrial with worm gear reduction.
What Fails on This Unit
Oil bath reducers need their oil. Level and condition are a maintenance item, and a reducer run low or contaminated is how a very long-lived unit dies early. The air breather matters too, blocked, it pressurises the housing and pushes oil past the seals.
Otherwise it is the solenoid brake, as on any brake-equipped model, and the drive chain and sprockets.
Manufacturer Documents
Originals from Manaras-Opera, useful if the paperwork for a unit already in your building has gone missing:
Choosing Between Models
The MGH is the larger 40:1 worm gear unit for heavier doors again. 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 OGH?
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.