Eaton Power Circuit Breaker MDS-508

Verify breaker secondary disconnect pins are fully seated and locked by lightly pulling on each wire individually

Ensure all pins are straight without bends, corrosion, or evidence of arcing

Note any damaged pins and refer to the renewal parts catalog for replacement

Ensure all power is removed from the cassette secondary pins

Charge the breaker mechanism springs

Close the breaker by applying rated voltage to the spring release accessory

Verify closing by noting the state of the indicating flag

Charge the breaker mechanism springs again

If using the motor operator, disconnect power to prevent automatic recharging

Check if the pop-out trip indicator is 'out'

Verify device (Fixed) position of poles is open

Verify device (Fixed) mechanism is discharged

Verify device (Drawout) position of poles is open

Verify device (Drawout) mechanism is discharged

Verify device (Drawout) position in cassette is removed

For Magnum Breakers with Vertically Mounted Primary Disconnects

Verify vertical adapter nuts and bolts are torqued to 37–43 lb-ft

For All Magnum Breakers Primary Disconnects

Review accessory voltage rating before energizing

Charge the breaker mechanism springs using the motor operator

Energize the UVR with the rated voltage if equipped

Close the breaker by applying rated voltage to the spring release accessory

Verify closing by noting the state of the indicating flag

Charge the breaker mechanism springs using the motor operator again

Inspect the breaker for nicked wires, cracks in plastic parts, and loose screws.

Tighten screws or bolts to levels outlined in Table 22.

Apply thread-locking compound to loose screws inserted into plastic parts.

Replace or repair all nicked wiring in accordance with accepted industry practices.

Are the torque values of the operating mechanism and motor mounting hardware within the recommended values in Table 18?