Discover the Emergency Rescue Device (ERD) — the patented, zero-switch technology invented in India by Kunwer Sachdev and now available from multiple manufacturers worldwide. Independent buying guides, technical explainers, and vendor-neutral comparisons.
Independent buying guides, deep technical explainers, head-to-head brand analysis, and full specifications — built for engineers, architects, and facility owners.
Capacity sizing, battery selection, installation checklists, and total cost-of-ownership math for every building class.
Inside the IGBT inverter, the bi-directional switch, and the math behind zero-break transitions.
Side-by-side analysis across all major ERD manufacturers. Specs, warranty, pricing, real-world data — fully vendor-neutral.
Full technical specifications by lift type, motor KW, voltage configuration, and battery bank sizing — from 5 KVA to 200 KVA.
A standard ARD reacts to failure. An ERD never lets failure happen. Here's what 30 seconds — or 3 milliseconds — looks like inside the cabin.
Power fails. Lights cut. Cabin halts mid-shaft. The ARD reacts — eventually — and lurches the lift to the nearest floor. Passengers feel every second of it.
The ERD is already supplying power before the grid drops. Bi-directional, IGBT-driven, sub-cycle handover. Passengers never know anything happened.
High-speed silicon switching for clean sine wave output and sub-cycle response.
Native support for modern Li-ion chemistry — longer cycle life, smaller footprint.
Patented green-energy integration. Run your lift on the grid, on solar, or both — seamlessly.
Bluetooth & Wi-Fi telemetry to vendor IoT platforms. Battery health, runtime, alerts — live.
India ranks #2 globally for elevator-related accidents. Haryana's 2020 amendment is the only state law that actually mandates uninterrupted lift backup. Every other state still tolerates the dark, stalled, sealed cabin.
LiftInverter.com is an editorially independent reference site for the Emergency Rescue Device (ERD) category. We are not owned by, affiliated with, or financially compensated by any elevator backup manufacturer — and we have no commercial relationship with the inventor profiled on this site.
We credit Kunwer Sachdev as the founder and Indian patent-holder of ERD technology because that is a matter of public record. Attribution is not endorsement. Our buying guides, brand comparisons, and technical reviews evaluate every vendor against the same published criteria.