Mini Size ATS Automatic Transfer Switch 3P 100A 220V - Compact Home

In this review the Mini Size ATS from JOTTAELE is evaluated as a compact automatic changeover solution for household emergency power. The bottom line: this unit is best for homeowners or small workshop owners who need a simple, DIN rail mounted transfer switch that switches to a generator when the grid fails. Its single biggest reason to buy is the reliable automatic transfer behavior that gives priority to mains power while switching to generator within a short transfer speed window to keep critical loads running.

Key Features

• Automatic transfer: Switches from mains to generator automatically when the main power fails so connected loads stay powered without manual intervention.
• DIN rail mounting: The compact PC type design is sized for installation inside standard DIN rail distribution boxes for neat, space-saving setup.
• 100A rated current: Supports a continuous 100A load which covers most household circuits and small workshop panels.
• 220V 50/60Hz compatibility: Built for standard single-phase 220V systems and compatible with both 50Hz and 60Hz supplies.
• Fast transfer speed: Transfers in less than 8ms, limiting interruption to sensitive electronics and essential appliances during switchover.
• Priority logic: Returns to mains automatically when grid power is restored, ensuring the generator is used only as a reserve source.

Who It's For

This ATS is aimed at homeowners, small business owners, and RV or tiny home builders who need an affordable, space-conscious automatic transfer switch to maintain power to essential circuits during outages. Its DIN rail form factor makes it especially useful where distribution space is limited.

Those who need multi-circuit metering, multi-phase commercial switching, or integrated generator start/stop controls should look elsewhere, as this unit is strictly a compact changeover switch and does not include advanced generator management features.

Pros & Cons

Pros

• Automatic, fast switching behavior preserves continuity for sensitive loads thanks to less than 8ms transfer time.
• Compact PC type housing designed for neat DIN rail installation in residential panels.
• Solid rated specification with 100A and 220V 50/60Hz compatibility for common household setups.
• Prioritizes mains supply automatically, reducing unnecessary generator runtime.

Cons

• Some buyers report mixed build quality and installation experiences, so careful inspection and professional installation are advisable.
• Does not include generator start/stop control or multi-phase support, limiting use to single-phase reserve setups.

Specifications

Product Type	Automatic Transfer Switch (Mini ATS)
Rated Current	100A
Rated Voltage	220V
Rated Frequency	50/60Hz
Transfer Speed	Less than 8ms
Mounting	DIN Rail (PC type mini size)

Our Verdict

The Mini Size ATS is a practical, value-oriented choice for homeowners and small installations that need a compact, automatic changeover solution. It delivers fast switching, standard 220V/100A ratings, and tidy DIN rail mounting, making it good value when paired with a properly sized generator and professional installation.

Frequently Asked Questions

Will the ATS switch if the generator is off?
The ATS will only transfer to the generator circuit if the generator is running and supplying reserve power; it will not energize the generator.

Can it be used in a multi-phase system?
This model is intended for single-phase 220V setups and is not designed for three-phase commercial installations.

Is professional installation required?
While some users install it themselves, mixed reports on build quality and wiring suggest hiring a qualified electrician is recommended for safety and correct operation.