This instruction leaflet (IL) gives detailed procedures for installing the UVR. The UVR can be field-installed in E2N and E2NM mining circuit breakers. The undervokage release mechanism (UVR) monitors a voItage (typically a line voltage) and trips the circuit breaker when the voltage falls to between 70 and 35 percent of the UVR rating (Figure 1-1). The UVR con-sists of a continuous rated solenoid with a plunger and reset lever assembled to a. How to install a shunt or undervoltage trip on a PowerPacT H, J, or L frame breaker Product Line: Molded Case Circuit Breakers Make sure the breaker is in the tripped position, remove the accossory cover, and install the shunt or undervoltage in the bottom left slot in the breaker (labeled MN/MX).