Automatic transfer switches, 10 A to 150 A
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.
- Current rating
- 10 A – 150 A
- Phases
- Single phase and three phase
More views of the Automatic Transfer Switch (ATS)
Detail 
Terminations 
Installed on site
And when it’s the right answer
An ATS watches the incoming supply and, when it fails or drifts outside limits, transfers the load to a second source. When the first supply comes back and stays back, it hands the load over again. Nobody has to be at the panel for either half of that.
The mechanism is what matters more than the electronics. The two sides are interlocked so both sources can never be connected at the same time — that is the whole safety case for a changeover switch, and it is built into the mechanism rather than left to control logic to remember.
We build these from 10 A to 150 A, in single phase and three phase. On a standard 415 V three-phase board, 150 A is a little over 100 kVA of connected load; on a 230 V single-phase board it is around 34 kVA. Above that range this is not the right switch — tell us the load and we will say so.
A manual switch needs somebody standing at it. Anywhere unmanned, or on a load where a few minutes of downtime is costly, that is not good enough.
A UPS bridges seconds to minutes on its battery. An ATS bridges for as long as the second supply holds. On a serious installation you have both, with the UPS covering the gap while the changeover happens.
Where these get installed
- Mains to standby-supply changeover in commercial buildings
- Hospital essential-services sub-boards
- Server room and IT distribution boards
- Machine and process sub-panels
- Telecom sites and BTS
- Cold storage plant rooms
Full specification
Typical values for the standard build. Every unit is configured to order — the figures on your general arrangement drawing are the ones that apply.
| Current rating | 10 A – 150 A |
|---|---|
| Phases | Single phase and three phase |
Sectors that buy this
Hospitals & Diagnostics
The load list in a hospital is not one load. Theatres, imaging, ICU and the server room each need a different answer, and the specification has to hold up in an NABH audit.
Data Centres & Server Rooms
Redundancy topology, battery runtime to DG pickup, and heat rejection. At this scale the UPS is the easy part of the specification.
Cold Storage & Food Processing
Compressor motors are unforgiving of low voltage, and the stock in the chamber does not care whose fault the outage was.
Telecom & Networks
Telecom runs on −48 V DC and on sites nobody visits. Modular redundancy and remote telemetry are the whole specification.
Automatic Transfer Switch (ATS) — questions we get asked
Anything not covered here, call us — most of it is faster to answer on the phone.
Do you make single phase and three phase?
Both, across the whole 10 A to 150 A range. Which one you need follows from the board it is going into rather than from the switch — a single-phase board takes the single-phase unit, a three-phase board the three-phase one.
How is the rating chosen?
By the full-load current of the distribution downstream of the switch, with headroom on top. The common mistake is sizing against the source instead: the rating of the incoming supply, or of the generator, tells you nothing about what the connected load actually draws.
What if my load is above 150 A?
Then this is not the product. 150 A is the top of the range, and there is no sense specifying a switch at its own limit anyway. Send us the load figures and we will tell you straight whether we can help.
Where we supply and attend
Automatic Transfer Switch (ATS) units are built at our Pune works and delivered, installed and commissioned across the city and the industrial belt around it.
Outside these areas we contract individually against distance, and we will tell you honestly if the response time you need is not one we can hold to. All areas served
After it’s installed
We service what we build, and what everyone else builds too.