Cornell Dubilier announces its new, patented, PCD series of high current, AC harmonic filter capacitors offering dual, built-in, fail-safe protection systems, one at each end of the capacitor.
Similar capacitors in this category have one open-circuit pressure device located under the top cover that requires the capacitor to be mounted from its bottom stud. With the addition of a bottom pressure device, the PCD’s terminals can be fixed to a rigid busbar allowing for activation of the bottom safety device when proper clearance is provided at the bottom. When activated, the bottom pressure device expands outward like a bellows.
While these fail-safe devices are designed to prevent case rupture at end-of-life, PCD series capacitors are designed to be exceptionally reliable with a service life of over 60,000 hours at rated voltage and temperature. Self-healing, metalized dielectric construction adds to their reliability.
The PCD series is offered with capacitance ratings ranging from 20 µF to 125 µF at voltage ratings from 240 Vac to 600 Vac 50/60Hz. Case diameters vary from 63.5 to up to 116mm. Custom capacitance and voltage ratings, sizes, and performance characteristics are also available. Specific application conditions, especially harmonic content profiles, are needed to properly size the capacitors for peak performance. Standard terminations are M6x1 threaded, tin-plated brass. Other termination types are available.
Additionally, PCD capacitors have robust construction allowing their use in high humidity environments. The series has been tested at Temperature-Humidity-Bias for 1000 hrs. at 85°C/85% RH, which places them in the highest climatic category of Class III-B, per IEC 60384.
Applications include UPS, AC-tuned filters, AC input filtering, line conditioning, noise suppression, variable-speed drives, and wind turbine monitoring. The PCD is an upgrade to European AC power film capacitors that usually have only a downward expanding interruption mechanism. The dual pressure interrupter of the PCD series gives the user maximum flexibility in mounting when fail-safe operation is of prime importance.