Telecom rectifier shelves combine parallel modules, forced airflow and frequent replacement. A small resistance mismatch can turn into unequal sharing and a hot spot at the blind-mate or board transition.
Match electrical paths before increasing copper
Map positive, negative and return paths across every parallel module. Match path length and contact pressure, then evaluate current sharing under minimum airflow and maximum ambient instead of relying on one cold-start measurement.
Keep the busbar inside the cooling and service envelope
Place bars away from fan inlets and critical heat sinks, or provide a defined thermal path to the chassis. Blind-mate terminals need guide float, wipe and normal force without transferring insertion load into the PCB land.
- Record module load, airflow and shelf position
- Thermally inspect terminals, corners and board transitions
- Repeat resistance, temperature and alignment checks after cycles
RFQ and acceptance for telecom shelves
Provide voltage, current, overload time, airflow, altitude, insertion cycles, isolation, material and packaging direction. Acceptance should capture sharing, voltage drop, temperature rise, dielectric results and dimensional traceability.