Boltswitch Capacitor Units

Originally designed for use with Boltswitch Shunt Trip Operators, these units may be suitable for use with other equipment as well. The units store energy to operate a shunt trip coil after the loss of control power.


The CAP-2 is designed for 120 VAC Shunt Trip Operators. Upon loss of control power, the relay switches the output from the normal source to the capacitor. The relay pick-up is approx. 85 volts and has a maximum inrush current rating of 15 amps and a maximum sealed current of 10 amps. The drop-out is approx. 72 volts.


The CAP-3 is designed for 125 VDC Shunt Trip Operators. The output is always from the capacitor. This device also has a resistor to slowly bleed the stored capacitor energy upon loss of control power. It will discharge to less than 50 volts in approximately 15 minutes. Terminals are provided for a remote neon lamp.

Size: 5" W x 7" H x 2.75" D
approximate net weight 1.5 Ibs
Mounting: Hole diameter: 0.25"
Hole spacing: 4.25" W x 6.25" H
Panel thickness: 0.38"
Minimum 0.5" clearance through air required between conductors and dead metal.
Input: 120 VAC
Tests: Tested in accordance with UL 508, "Industrial Control Equipment" and UL Listed under File No. E65261.
CAUTION: This device stores energy. The hazard of electric shock may remain with power off.