China LMS1-SN Series 400A Automatic Transfer Switch ATS - Reliable Supplier and Factory for Quality Power Solutions

LMS1-LA as our ingenuity research and development of a new generation of dual power automatic transfer switch, in the performance and technology to achieve a major breakthrough. The product provides 63A, 125A, 250A, 400A, 630A and other rated current specifications, whether it is the continuous operation of massive servers in data centers, or the uninterrupted power supply of life support equipment in hospital ICU wards, the stable operation of elevator and fire fighting system in high-rise buildings can fully meet the power demand in different scenarios. ​

LMS1-SN Series PC class dual power Auto Transfer Switch, mainly used in two-way power supply systems with rated voltage below 400V, AC 50/60Hz, rated current up to 630A. When one power supply becomes abnormal, it transfers between the two power supply systems to ensure power supply reliability and safety.

Model Description

⚠ Notice:

1. Separated type ATS can be chosen with Y-701 (LED) or Y-702 (LCD) Controller.

2. ATS without output signal to start generator; Y-701 and Y-702 controllers include it.

Working Environment

• ◆ Ambient Air Temperature: Ambient temperature -5℃ to +40℃, and the 24-hour average temperature value does not exceed +35°C. Users whose ambient air temperature is higher than +40°C or lower than -5°C should consult with the manufacturer.
• ◆ The Highest Temperature of Atmospheric Humidity: When the temperature is +40℃, the relative humidity does not exceed 50%, and the maximum relative humidity per month is 90%. Resistant to the influence of humid air on the sea, and can allow higher relative humidity at lower temperatures. Special measures should be taken for occasional condensation caused by temperature changes.
• ◆ Installation Altitude: The altitude of the installation site does not exceed 2000 meters. When used at higher altitudes, the dielectric strength and cooling effect of the air should be considered to be reduced; please consult with the manufacturer.
• ◆ Pollution Level: The environmental pollution level of the installation site is level 3.
• ◆ Installation Category: IV.
• ◆ Installation Inclination: The product is fixedly installed in the cabinet; the maximum inclination is ±22.5°.
• ◆ Arcing Distance: The arcing distance is 30mm when AC 400V. The arcing distance when AC 690V is 60mm.

Main Technical Parameters

Model Name			LMS1-SN
Insulation Voltage			AC 690V
Rated Voltage			AC 400V
Rated Current			20A~125A	160A~250A		315A~630A
Rated Impulse Withstand Voltage			8kV
Kind of Throw			Double Throw
Wiring Method			Front Board
Short-time Resistance Current			10kA
Through to Breaking Capacity			17kA
Transfer Time	A Power	Input	80ms		80ms		100ms
		Break	30ms		30ms		30ms
	B Power	Input	100ms		100ms		120ms
		Break	30ms		30ms		30ms
Electrical Life			1000				1000
Mechanical Life			5000				4000
Use Type			AC-33ib
Accessories			Manual Handle

Structure and Mounting Dimensions

Frequently Asked Questions

QWhat is the LMS1-SN Series ATS and what is it used for?

AThe LMS1-SN Series is a PC class dual power Automatic Transfer Switch designed for two-way power supply systems with a rated voltage below 400V (AC 50/60Hz) and rated current up to 630A. It automatically transfers between two power sources when one supply becomes abnormal, ensuring continuous and reliable power delivery.

QWhat controllers are available for the separated type ATS?

AThe separated type ATS can be paired with either the Y-701 (LED) or Y-702 (LCD) controller. Note that the standard ATS does not include an output signal to start a generator, but both the Y-701 and Y-702 controllers do support this function.

QWhat are the operating temperature and humidity requirements for the LMS1-SN ATS?

AThe unit operates in ambient temperatures from -5℃ to +40℃, with a 24-hour average not exceeding +35°C. At +40℃, relative humidity must not exceed 50%, with a monthly maximum of 90%. For environments outside these ranges, please consult the manufacturer for special arrangements.

QWhat is the maximum installation altitude for the LMS1-SN ATS?

AThe recommended maximum installation altitude is 2000 meters. At higher altitudes, the dielectric strength and air cooling effectiveness are reduced. Users planning to install the ATS above this altitude should consult the manufacturer for guidance and any necessary derating.

QWhat are the transfer times for Power A and Power B on the LMS1-SN?

AFor Power A: the input transfer time is 80ms (100ms for 315A–630A) and the break time is 30ms. For Power B: the input transfer time is 100ms (120ms for 315A–630A) and the break time is 30ms. These fast switching times help minimize power interruption to connected loads.

QWhat are the electrical and mechanical life ratings of the LMS1-SN ATS?

AThe LMS1-SN ATS has an electrical life of 1000 operations across all current ratings. The mechanical life is 5000 operations for models rated 20A–250A, and 4000 operations for models rated 315A–630A, ensuring long-term reliable performance in critical power switching applications.