Description

This package targets control cabinets, pump control boxes, or air-handling unit panels where relay or contactor bases exhibit oxidized contacts, fatigued springs, causing unstable coil holding, intermittent signal transmission, or frequent false operations. We begin by marking and recording each control conductor connected to the faulty base, taking photographs to document original wiring positions to ensure accurate restoration. The old base is removed from the DIN rail, and the adjacent lug terminals are cleaned, de-oxidized, and lightly coated with contact grease in preparation for the new base installation.

After the new base is mounted, we reconnect conductors according to the recorded wiring scheme, checking each conductor’s insulation sheath for pinch marks or damage, applying heat-shrink tubing for local reinforcement where needed. Upon completion, we perform functional simulation tests—applying rated control voltage to the relay coil for at least ten successive operations, observing contact closing and opening synchronism and reliability to ensure full compatibility with the existing control logic. After passing tests, we affix a replacement date label and contact rating parameter tag beside the base.

This replacement’s component selection and installation process are fully adapted to the cabinet’s internal space, original base mounting hole positions, and control signal circuit distribution. A deposit is required before starting, covering the procurement of compatible or functionally equivalent replacement bases and marking materials, with the amount estimated based on the number of bases to be replaced and their unit purchase prices. After all replacements and tests are finished, the final balance is based on the actual number of bases replaced and the on-site commissioning time.