Power cuts and load shedding are a fact of life for many factories, hospitals, offices and apartments in Bangladesh. A generator is only half the answer — you also need a safe way to switch your load between the utility and the generator. That is the job of a changeover switch or an ATS panel.
Manual changeover switch
A changeover switch lets an operator move the load from the utility line to the generator by hand. It is simple, robust and low-cost. Its mechanical design ensures the two sources can never be connected together. The downside is that someone has to be present to start the generator and operate the switch, so there is always a delay.
Automatic changeover switch (ATS panel)
As our ebook explains, an ATS (Auto Changeover Switch) panel means you do not have to switch to an alternative power supply, such as a backup generator, by hand when there is a power outage. The ATS switches automatically, reducing the risk of data loss, damage to electrical equipment or disruption to your business.

How an ATS panel works
- The ATS controller monitors the utility voltage on all three phases.
- When the supply fails or goes out of range, it sends a start signal to the generator.
- Once the generator voltage and frequency are stable, it opens the utility breaker and closes the generator breaker.
- When the utility returns and stays stable, it transfers the load back and lets the generator cool down before stopping it.
Mechanical and electrical interlocks make sure the utility and generator are never connected at the same time.
What goes inside an ATS panel
- two motorised MCCBs or ACBs, or two contactors for smaller ratings
- an ATS controller or relay logic with timers
- voltage monitoring relays
- mechanical and electrical interlocking
- indicator lamps, selector switch and meters
How to size an ATS panel
The ATS rating must match the full current of the load it switches — usually the generator’s rated current. For a three-phase generator at 415 V, the current is about 1.39 A per kVA. A 250 kVA generator, for example, needs roughly a 400 A ATS.
What affects the ATS panel price in Bangladesh
- the current rating (from a few amps to several thousand)
- breakers or contactors as switching devices
- the brand of breakers and controller
- extra features: generator auto-start, load shedding, remote monitoring
- enclosure size and finish
Frequently asked questions
Can an ATS work with any generator?
The generator needs an auto-start control. Most modern diesel generators have this. We check compatibility before supply.
Where is the ATS installed?
Usually between the generator, the utility supply and the LT panel or MDB, so the whole building or selected essential loads are backed up.
Get an ATS panel quotation
Tell us your generator size and the loads you want backed up. We will recommend a manual changeover or an ATS and send a clear quotation. See our ATS panel range or request a quotation.
বাংলায় পড়ুন: এটিএস প্যানেল ও চেঞ্জওভার সুইচ: জেনারেটরের স্বয়ংক্রিয় ব্যাকআপ




