How to efficiently protect your critical loads?
Primax critical distribution panels offer the most efficient way to protect your critical loads. The option of using a combination of branch fuses in series with circuit breakers achieves ultimate protection when it comes to protecting AC or DC critical loads fed by UPS and battery systems.
While the national safety codes provide the basic requirements for over-current protection devices (OCPD), breakers and fuses are available to provide overload, short-circuit and ground fault protection in power distributions systems. However when it comes to power distribution in UPS and dc systems applications, additional considerations must be taken in account such as the limited power provided by the UPS in contrast with a relatively infinite power provided by the electrical utility:
AC UPS: normally in an over-current event and depending on the time that this over-current lasts, UPS may shut-down and transfer loads to bypass/utility until the fault is cleared. Circuit breakers may take few cycles to trip, risking a load disruption and load reset.
DC systems: In the same way, in a dc system faulty load may drain or affect DC bus voltage disrupting the other DC loads.
Fast acting fuses operate in a sub-cycle period of time, typically in 1/4 of a cycle. A well sized and coordinated fuse/breaker can easily prevent undesired loss of critical loads.
At Primax, selective coordination and sizing of OCPD is closely done with the sizing of the UPS and DC system.
Voltage ratings: 24-600 Volts ac or dc
Bus current: up to 2000A
Mains protection: Main breaker or lugs
Branch protection: molded case or mini DIN type breakers, fast acting fuses or a combination of breakers and fuses in series.
Interrupting current: 3kA up to 100kA
Ground fault: AC or DC
Mounting: front access wall, standalone or 19”rack. No extra side or back space is needed.
Standard protection: NEMA 1 – IP 20
OCPD: 1, 2, 3 or 4 pole feeders, High interrupting fuses and breakers, rate field adjustable breakers
Accessories: Breaker shunt trips, bell and trip alarms, fuse open alarm
Transients: TVSS-Lightning protection, internal or external
EPO: Local or remote Emergency Power Off
Monitoring: Voltmeters, ammeters, power quality meters, Blown fuse indication, indicating lights
Locking: Mechanical or electrical interlocking, Kirk-key
Connections: Direct or via terminal block connections
Alarms: Low and high voltage alarms, ground leakage, phase failure, , form C contacts for remote indication
Mechanical: Ground bus, Seismic design, dust and water protection, Matched cabinets to UPS and battery chargers, enclosure heater and thermostat, outdoor insulation and conditioning, dust filters, integration within UPS and Charger enclosures, safe fuse holders up to 60A
Spare spaces: Empty or pre-bussed
Others: branches individual current readings, cabinet internal lights, 120-240V outlets, 4-20mA transducer, Modbus and communication.
Few pictures of panels we have built: