Lift inverters and battery backup for elevators
More than 700 lift backup units installed in Hyderabad, and a growing book across Pune. This is the part of a building where a power cut stops being an inconvenience and becomes a rescue call.
What actually goes wrong
A DG takes eight to fifteen seconds to start and load, assuming it starts. In that window the car is stationary between floors with people in it, and if the DG fails to start the wait becomes an hour and a phone call to the fire brigade. A lift inverter is independent of both the DG and the incoming supply, and it acts in under a minute. Lifts are the sector we have installed in most — more than 700 units across housing societies, commercial buildings and hospitals — so the controller interfaces are territory we already know.
Working in elevators & building services
What to get right
The decisions on this list are the ones that are expensive to change after the equipment is on site.
Regenerative load
A descending loaded car feeds power back into the drive. A lift inverter absorbs it; a general-purpose one trips or is damaged.
Controller compatibility
VVVF controller interfaces differ between makes. There is no universal wiring — the machine room gets surveyed before quoting.
Machine room temperature
Terrace machine rooms in Pune run above 40 °C in summer, which can halve battery life. Annual load testing is not optional.
Direction of least load
The car should travel the direction that requires least energy. Correct commissioning is what makes the rescue reliable at low state of charge.
Building-wide services
Fire panels, emergency lighting and access control also need holdover. They are usually forgotten until the handover inspection.
Statutory position
Lift rules are state-administered. Check the current Maharashtra rules and your lift inspector for what applies — a lift inverter is standard specification on new commercial work regardless.
What we supply into this sector
Lift Inverter
Not a rescue device that parks the car and stops. The lift keeps running — normal service, normal speed, up to eight hours on battery — so a power cut in a residential tower is something the residents never find out about.
Lift ARD (Automatic Rescue Device)
One job, done properly: nobody is left standing in a dark car between two floors. On mains failure the ARD takes the lift to the nearest landing, opens the doors, and stops.
Automatic Transfer Switch (ATS)
The supply you are on fails, and the load moves to the one that has not — with nobody at the panel. 10 A to 150 A, single phase and three phase.
Servo Voltage Stabilizer
5 kVA to 500 kVA, air or oil cooled, correcting to ±1% output. The right first fix when the MIDC feeder swings all day and the equipment keeps tripping on undervoltage.
Online UPS
True double-conversion topology from 3 kVA to 200 kVA across three series, with single-phase or three-phase output. Zero transfer time, pure sine output held to ±1%, and up to 96% efficiency. Built and load-tested in Pune.
Through the life of the machine
Questions we get asked
Anything not covered here, call us — most of it is faster to answer on the phone.
01Can a lift inverter be retrofitted to an existing lift?
In most cases yes. We need the machine rating, the drive type and the controller make, and the machine room gets surveyed first because the interface differs between VVVF controllers. Retrofitting does not normally require replacing the drive.
02How long does the lift keep running on backup?
It does not need to — the lift keeps running. A backup system carries normal service at normal speed for up to eight hours, so the car in transit completes its journey and the next passenger never knows the mains failed. A controlled landing only happens at the end, if the bank runs down before the supply returns.
03Is an automatic rescue device mandatory in India?
Treat it as required and confirm locally. ARDs are named as a required safety feature across the Indian lift codes and most state Lift Acts, and enforcement in Maharashtra has tightened. The code position also moved recently: IS 17900, based on EN 81-20/50, superseded IS 14665, IS 15785 and IS 14671 for new installations from 22 December 2025, while adoption into individual state Lift Acts is happening state by state. Older lifts remain certified to the code they were installed under. Confirm the current position for your building with your lift contractor and the state Electrical Inspectorate before ordering — we build to the specification you are given.
04What is the difference between a lift ARD and a lift inverter?
Scope. An ARD is a rescue device: on mains failure it moves the car to the nearest floor, opens the doors and stops. A lift inverter keeps the lift in normal service — full speed, full travel, calls answered — for as long as the battery lasts. An ARD prevents entrapment; an inverter prevents interruption. A residential building with a generator usually needs the first. A hospital, hotel or a building with no DG usually wants the second.
05Will an ARD or lift inverter work with our VVVF controller?
Generally yes, but the interface is the thing to check, not the rating. VVVF drives differ in how they signal a supply failure and how they expect the rescue sequence to be initiated, and some regenerate into the supply on descent. We ask for the controller make and model, the drive type and the machine rating before quoting, and survey the machine room on anything we have not interfaced with before.
06Does a lift on a DG set still need backup?
Usually, because of the gap. A generator takes time to start, accept load and stabilise, and during that window the car is stationary between floors with passengers in it. An ARD or inverter covers the changeover, and it also covers the case every building eventually meets — the DG that does not start. Sizing also matters here: lift starting current is well above running current, and a lift is one of the loads most likely to be underestimated on a DG.
We will do the load grading with you
Site survey, load list and a single-line diagram before anything is quoted. That is where the specification is actually decided.