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Asco 300SE Non-Auto Transfer Switch (1Ph, 800A)


SKU: H03NUSA20800FG Category Tag Brand:
Availability: Please call for current lead time
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This ASCO Series 300 SE Non-Automatic Transfer Switch is electrically operated and manually initiated for single phase loads up to 800A. Service Entrance rated. Designed for commercial, telecom, municipal, light industrial, and agricultural applications.


  • Ideal for applications where operating personnel are available and the load is not an emergency type requiring automatic transfer of power.
  • Transfer is manually initiated via soft key on the user interface panel.
  • Controller prevents inadvertent operation under low voltage condition.
  • Source acceptability lights inform operator if sources are available to accept load.
  • Source in-phase monitor to transfer motor loads between live sources.
  • Two auxiliary contacts closed when transfer switch is connected to normal and two closed on emergency standard feature 14AA/14BA.
  • True double-throw operation: The single solenoid design is inherently inter-locked and prevents contacts from stopping between sources or from being in contact with both sources at the same time.
  • Operating parameters and feature settings can be adjusted without opening enclosure door.
  • Supplied with solid neutral termination.
  • Compact design for optimum utilization of space.
  • Designed to be completely front- accessible, permitting the enclosure to be installed flush to the wall and still allow installation of all power cables and connections from the front of the switch.
  • Numerous enclosure options including UL Type 1 (indoor) and UL Type 3R (outdoor).
  • Accessory 44A Strip Heater is now included for all models with a 3R outdoor enclosure. Prevents condensation and freezing that can shorten the life of the ATS. External 120 volt power source required. Thermostat included.
  • Accessory 11BE Feature Bundle is now included with all new Asco 300 ATS. This accessory offers an event log, enabled RS-485 communication port, and common alarm output contact.
  • UL 1008 Listed and CSA Certified.


  • Suitable for use as service entrance equipment. Listed to UL 891 (standard for switchboards) and meets all NEC requirements for service entrance use.
  • Circuit Breaker disconnect on the normal for isolation of transfer switch and other electrical equipment.
  • Disconnect link on Neutral and Ground.
  • Silver plated copper ground and neutral bus with solderless screw type terminals.


Asco Series 300 New Microprocessor Controller (Group G)

  • groupg-lcd-sm.jpgEasy to navigate 128×64 graphical LCD display with keypad provides soft keys for transfer and monitoring, as well as LED indicators for switch position, source availability, and alert condition.
  • Integrated multilingual user interface for configuration and monitoring.
  • Adjustable time-delays for transfer and re-transfer as needed.
  • Source inphase monitor to transfer motor loads between live sources.
  • Voltage and frequency sensing.
  • Statistical transfer switch system monitoring information.
  • Diagnostic functions.
  • Password protection to prevent unauthorized tampering of settings.
  • Further details can be found in the brochure and controller guide below. See pictures above for informative visuals.


Asco 300 Brochure

Asco 300 SE Supplement

Asco 300 Microprocessor Controller

Asco 300 Warranty


Please Call to Order Transfer Switches With These Options:

  • Switched neutral pole (solid neutral is standard).
  • Delayed Transition configuration for transfer of loads between power sources with a timed load disconnect position for an adjustable period of time of 0-5 minutes.
  • Other 60Hz voltages – up to 600 VAC.
  • 50Hz frequency/voltages.
  • Secure enclosures: UL Type 4, 4X, or 12.
  • Extended warranties: 3, 4, or 5 years.

Please Note: Some Specs (including withstand ratings, dimensions, and weights) may vary with some of the options above.


Please see below for more information and to order. Accessories ordered with your transfer switch will be factory-installed (as applicable).

  • acc-1up-sm.jpgAccessory 1UP UPS Back Up Power – Allows controller to run up to 3 minutes without AC power. (Also available as a customer-installed Field Kit.)
  • acc-18rx-sm.jpgAccessory 18RX Relay Expansion Module (REX) – Provides for some commonly used accessory relays, includes one form C contact for source availability of normal (18G), and one contact for availability of emergency (18B). Contact rating is 5 amps @ 30VDC or @ 125 VAC resistive). Additional output relay is provided, the default is to indicate a common alarm. See operator’s manual for configurable options. (Also available as a customer-installed Field Kit.)
  • Accessory 135L Power Meter 5210 – For enhanced monitoring of power and energy information on the load side. Includes shorting block and CT’s. (Also available as a customer-installed Field Kit. Not compatible with Accessory 23GA/23GB.)
  • acc-23g-sm.jpgAccessory 23GA/23GB Load Current Metering Card – Measures either single phase (23GA) or three phase (23GB) load current. Includes CT’s. (Not compatible with Accessory 135L.)
  • acc-72ee-sm.jpgAccessory 72EE Quad Ethernet Module – Enables remote monitoring and control capabilities. Includes Accessory 11BE Feature Bundle. (Also available as a customer-installed Field Kit.)
  • Single Channel 5310 Annunciator – Provides remote monitoring and control of one Asco 300 transfer switch. Requires Accessory 72EE. (Not factory-installed.)
  • Eight Channel 5350 Annunciator – Provides remote monitoring and control of one Asco 300 transfer switch. Requires Accessory 72EE. (Not factory-installed.)
Model Number






Withstand Rating w/ Circuit Breaker

Withstand Rating w/ Fuse


AIC Breaker Rating

Service Entrance Rated

Frame / Cabinet Type

Full Dimensions HxWxD (inches)

Weight (NEMA 1)

Weight (NEMA 3R)

Limited Warranty


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