Power Transfer Switches

ASCO SERIES 185 Power Transfer Switch

Get all the intelligence your optional standby system needs to make sure power stays on when the utility fails, with ASCO SERIES 185 Power Transfer Switches. When utility power has been restored, this line of power transfer switches will automatically transfer your loads back to utility and shut down the generator, saving fuel and standing ready to address the next utility failure.

Best Suited For
  • Banking, Financial and Insurance
  • Broadcast and Entertainment
  • Construction and Engineering
  • Data Center/Colocation/Hosting
  • Education
  • Fire/Alarm/Security
  • Government
  • Healthcare
  • Manufacturing
  • Power Generation
  • Power/Gas Transmission and Distribution
  • Retail and Wholesale
  • Telecom
  • Transportation
Twenty Four Month Limited Warranty


Specifications per model ASCO SERIES 185
Ampere Size Pole Count Voltage Enclosure Type Height (in / mm) Width (in / mm) Depth (in / mm) Weight (lbs / kgs)
100 through 400 Single 240V NEMA Type 1 and Type 3R 24 - 48 in / 610 - 1219 mm 14.25 - 24 in / 362 - 610 mm 8.25 - 10 in / 210 - 254 mm 44 - 118 lbs / 20 - 54 kgs
* To view a specific model product page click on the model name above.
Intended Applications
Ampere Size
100A - 400A
Pole Count


User-friendly control interface with easy to understand symbols and visual indicators to inform operator of transfer switch and power source status.
Listed to UL 1008 for optional standby systems, handling total system load including motors and all other electrical loads.
cUL Listed for Canadian installations.
Available in 100 through 400A ratings.


True double-throw contacts with inherent mechanical interlocking to prevent connection of generator and utility sources.
Terminals for convenient connection of neutral and ground conductors.
Working hand in hand with virtually every brand of generator, ASCO SERIES 185 Power Transfer Switches provide around-the-clock protection from a power failure, taking action only when required.

Services & Support


Frequently Asked Questions
How do I perform a transfer test?
1. To perform a test, press and hold the transfer test button for at least 15 seconds or until the generator cranks. 2. Wait for approximately 10 seconds for the transfer to generator time delay. 3. Press the Bypass Time Delay button for immediate load transfer to the generator.
Why doesn’t the engine exerciser light blink to indicate the remaining number of days until the next exercise period?
After the exercise period stops, the flashing light will remain on to indicate that the exercise is enabled and another exercise will be conducted after a week.
How does the engine exerciser work?
The engine exerciser works by closing the engine start contacts and keeps it closed in order to crank and run the generator for approximately 20 minutes; after time expires, the controller signals the engine start contacts to open up and shut the generator down (after the 5 minute engine cool down period).
Will the 185-switch work with a non-generator emergency source?
YES, it will work with a non-generator emergency source. As long as you have provided the necessary power cables to the transfer switch.
Where is the ground bus located?
Upon opening the enclosure door of the transfer switch, the ground bus / lugs are located on the right side of the enclosure.


Sales In USA Change Location
ASCO Power Technologies (Maryland, Southern Delaware, Washington DC and VA
Email Contact 571 313 8041 Fax 703 342 0391
12310 Pinecrest Road Suite 204 Reston Virginia 20191
Product areas of focus: Power Transfer Switches, Paralleling Switchgear, Power Control and Monitoring
Support Change Location
ASCO Services, Inc.
50 Hanover Road Florham Park New Jersey 07932
Product areas of focus: Power Transfer Switches, Paralleling Switchgear, Power Control and Monitoring


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