Modern lifts are among the safest ways to travel, because they are designed with several independent layers of protection. Here is what the most important ones do — without the jargon.
Automatic Rescue Device (ARD)
If the mains power fails, the ARD switches to battery power, moves the car slowly to the nearest landing and opens the doors. Without it, passengers may have to wait for manual rescue.
Infrared light curtain
A full-height curtain of infrared beams across the doorway detects people, bags or pushchairs. If anything breaks the beams, the doors stop and reopen — far more reliable than a single sensor at one height.
Overload protection
A load-weighing device detects when the car is carrying more than its rated capacity. An alarm sounds and the lift will not move until the load is reduced.
Overspeed governor and safety gear
The governor constantly monitors car speed. If the car ever travels faster than a set limit downward, the governor triggers the safety gear — mechanical clamps that grip the guide rails and bring the car to a controlled stop.
Door interlocks
Landing doors are locked unless the car is at that floor, and the lift cannot move unless all doors are closed and locked.
VVVF drive control
A variable-voltage, variable-frequency (VVVF) drive controls the motor precisely, giving gentle acceleration, soft deceleration and accurate floor levelling — which also reduces trip hazards at the threshold.
Why layers matter
No single device is relied on alone. Electrical safeguards (door interlocks, overload sensing, controller monitoring) stop the lift before a problem develops, while mechanical safeguards (governor and safety gear, buffers in the pit) work even if electrical systems fail. Good maintenance keeps every layer working.
What maintenance should check
- ARD battery health and an actual rescue test
- Light-curtain alignment and response at different heights
- Governor and safety-gear operation, rope and rail condition
- Door locks, door operator and closing force
- Overload device calibration and levelling accuracy
A structured Annual Maintenance Contract makes these checks routine rather than reactive.
Questions to ask your supplier
- Is an ARD included as standard?
- Is the door sensor a full-height light curtain?
- Which standards do the components comply with?
- How are safety devices tested at handover and during maintenance?
Every Sakshi lift is designed with multi-layered safety — see the safety systems on each lift page.
