Technical FAQs

Ask a Question

Masterpact NT NW Maintenance and testing after storage. What are the required storage conditions?

Issue:
Is a Masterpact breaker okay to be installed after extended storage?

Product Line:
Circuit Breakers

Environment:
Masterpact NT NW

Resolution:

Storage Conditions
Devices must be stored in a dry, ventilated area, protected from rain, water and chemical agents. They must be well protected against dust, rubble, paint, etc.
If storage is for an extended period, the following storage conditions are necessary:
• relative humidity in the room must be maintained below 70%.
• circuit breakers with trip units without LCD displays may be stored in the original packaging at temperatures between -40 °F to +185 °F (-40 °C to +85°C).
• circuit breakers with trip units with LCD displays may be stored in the original packaging at temperatures between -13 °F to +185 °F (-25 °C to +85 °C).
• devices must be stored in the open (OFF) position with the charging springs discharged.

Checks and Maintenance
After extended storage, the checks below must be carried out before installation to ensure correct device operation.

Storage less than or equal to 2 years
Run the Level II and III second year program on the subassemblies below:
• mechanism
• trip unit
• device and cradle locking
• cradle

Storage > 2 years
Run the Level III and IV fifth year diagnostic program on the subassemblies below:
• mechanism
• control accessories
• trip unit
• device and cradle locking
• cradle

If the devices were stored under severe conditions (high temperature, corrosive atmosphere), it is necessary to:
• check the surface condition of the metal parts (zinc) and the copper parts
(silver coatings [Ag] or tinning [Sn]).
• check the greasing for the device and cradle.
• regrease the clusters and check primary contacts.
Was this helpful?
What can we do to improve the information ?