- 1 Year / 1,000 Hour Limited Warranty (Whichever comes first)
- 3 Pole
- Amps: 1000
- NEMA 3R Enclosure
- 3 Phase
SERIES 300 AUTOMATIC TRANSFER SWITCH
ASCO Series 300 automatic transfer switches are suitable for emergency and standby power system
Sizes 30 through 3000 amps in a compact design with 2, 3, & 4 pole configurations. Available 120 to
600VAC. UL 1008 listed to 480VAC for total system loads. True double-throw, inherently interlocked
construction. Mechanically held, electrically operated utilizing a reliable, field-proven single solenoid
operator. Contacts easily accessible for easy inspection and preventive maintenance. Meets National
Electric Code requirements (US). Rated for emergency and standby applications.
Available in Type 1 and 3R enclosures 30 through 3000 amps. Type 1, 3R, 4 and 12 from 30 to
1600 amps. Qualified and listed to CSA C22.2 No. 178 and UL 1008 automatic transfer equipment standards.
Control Panel Standard Features & Design Criteria
Motor load transfer controls (inphase monitor) to keep motors operating during transfer.
Pre-transfer & post-transfer load disconnect contacts for signaling motor starters, elevators, VFDs
and other selected loads.
Standard Engine Exerciser for weekly automatic testing of engine generator set with or without
Selectable control switches for voltage, frequency, time delay settings & additional control features.
Switch position lights, source availability lights, test switch and time delay bypass switch.
Standard Selectable Features
lnphase monitor to transfer motor loads without any intentional off time to help prevent motor inrush
currents from exceeding normal starting levels.
Engine exerciser to automatically test engine generator each week. Includes control switch for
testing with or without load.
Selective load disconnect, double-throw contact to operate at an adjustable 0 to 20 second time
delay prior to transfer and reset 0 to 20 seconds after transfer.
60 Hz or 50 Hz selector switch.
Three-phase/single-phase selector switch.
Voltage & Frequency Sensing
Adjustable three-phase, close differential voltage sensing on normal source.
Normal source pickup voltage is adjustable to 95% of nominal; drop-out is adjustable from 70 to
90% of nominal.
Frequency sensing on emergency source. Pickup at 95% and dropout at 85% of nominal.
Adjustable time delay to over ride momentary normal source outages to delay all transfer switch
and engine-starting signals.
Transfer to emergency time delay. Adjustable from 0 to 5 minutes for controlled timing of load
transfer to emergency.
Specifications may vary. Confirm full specs prior to ordering.