Standard Conditions for Machine Room-Less (MRL) Elevators
Machine Room-Less (MRL) elevators have gained widespread use due to their numerous advantages, especially in new construction and renovation projects. This type of elevator is also suitable for public spaces such as subways, passenger terminals, and large buildings like commercial complexes with open spaces and panoramic views.
In MRL elevators, the placement of doors or hatches and the overhead space for the motor are of particular importance. According to building regulations, installing these elements should not obstruct minimum passageways. Additionally, the overhead space for the elevator motor must be at least 0.3 meters. If this clearance is insufficient, a protective cover for the motor must be used.
For maintenance and inspection of MRL elevators, five access points can be utilized:
- Hatches located outside the elevator shaft for accessing the machinery
- The roof of the machine room-less elevator car
- Hatches on the walls of the MRL elevator cabin
- The pit floor of machine room-less elevators
- The platform of MRL elevators
Conducting Tests from Outside the Elevator Shaft
In addition to the capability for inspection and maintenance of machine room-less (MRL) elevators from five different positions, it must also be possible to perform dynamic tests, such as buffer tests, overspeed protective device tests during ascent, traction tests, safety gear tests, brake tests, and emergency rescue operations, from outside the elevator shaft.
To access machinery inside the shaft from an external workspace, this area must meet the following conditions:
- Sufficient Dimensions: The space should be large enough to perform necessary tasks through the hatch or door.
- Minimum Working Space: The size of the working space should be as small as possible to prevent falls into the shaft.
- Lockable Access: The workspace must have lockable access, which can be locked and secured without a key.
- Safety Electric Device: The workspace should have a safety electric device to control the locked state.
- Non-Inward Opening: The workspace should not open inward towards the shaft.
- Sealed and Electrically Resistant: The workspace must be free of any openings and have electrical resistance by elevator landing door standards.
- Fire Protection Compliance: The area should comply with building fire protection regulations.
Conducting Maintenance or Inspection from the Roof of a Machine Room-Less (MRL) Elevator Car
When performing tasks such as inspecting machinery or maintenance from the roof or inside the elevator cabin, the following considerations should be observed:
- Use of Mechanical Devices: To prevent dangerous movements of the cabin, mechanical devices such as park plates or fix plates should be utilized. If these devices are not operational, safety electrical devices or micro switches should be employed to prevent unintended cabin movement.
- Operational Safety: Safety measures must be in place to ensure the safe execution of maintenance operations and a secure exit from the work area.
- Inspection Through Cabin Wall Hatches: Inspection or maintenance should be possible through the hatches in the cab walls. If these hatches are present, they must be designed to allow access to the inside of the shaft without requiring entry into the shaft, as mentioned in previous paragraphs.
Conditions Required for Cabin Movement with Open Hatch:
- Access to the Inspection Box: The inspection box should be located near the inspection hatch for easy access.
- Deactivation of Hatch Micro Switch: The hatch micro switch must be deactivated using the inspection switch located inside the cab wall.
- Location of the Inspection Box: The inspection box should be installed behind the inspection door or hatch, ensuring that only the responsible person inside the cab has access to it.
Performing Maintenance or Inspection of Machine Room-Less (MRL) Elevators from the Pit
When carrying out maintenance or inspection of machinery from the elevator pit, specific conditions must be met:
- Mechanical Stopping Device: The selected mechanical device used to stop the cab must be capable of bearing the elevator’s rated capacity, and its stopping speed should not exceed the elevator’s rated speed. Additionally, when the cab is stopped, this device must ensure a minimum clearance of 2 meters between the pit floor and the lowest part of the cab. The mechanical device should not induce acceleration greater than that caused by the buffer.
- Returning the Elevator to Normal Operation: To restore the elevator to normal functionality, an electrical device capable of resetting the system must be used. This action should be performed from outside the shaft and only by authorized personnel. A safe location for this device is inside a locked panel. The mechanical stopping device must securely hold the cab in place, and its operation can be either manual or automatic.
- Considerations for Elevator Specifications: The dimensions, capacity, and type of the elevator vary depending on the type and purpose of the building. Most multi-story buildings are equipped with elevators, which are considered a significant asset to these structures.
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