Machine Room Electrical Distribution, Cable Selection, Earthing & Lightning Protection

Machine Room Electrical Distribution, Cable Selection, Earthing & Lightning Protection

Refrigeration machine room power load includes compressor, condenser fan, pump, control cabinet, defrost heater, lighting and alarm. Cable selection: consider starting current of compressor, low temperature resistance, oil resistance, flame retardant grade. Compressor power cable separate from sensor signal cable; separate trunking to avoid electromagnetic interference to PT100/NTC signal. Earthing system: all metal equipment, pipe bracket, control cabinet connect to equipotential earthing bar, anti-static and electric leakage. Three phase power balance monitoring; long-term unbalance will increase motor heating and shorten compressor service life. Xiteliduo export machine room electrical scheme complies with IEC standard, optional local certification such as UL. Lightning protection: outdoor condenser and rack metal frame connect to lightning protection system for thunderstorm area. Emergency power supply (UPS): for controller, alarm, gas detector; avoid losing monitoring and alarm during mains failure. Defrost heater is large resistive load; separate circuit and contactor, overcurrent protection matched for heater. Refrigeration maintenance & repair company measures earthing resistance and three-phase current balance periodically.

FAQ

1. Why separate power cable and sensor signal cable? Prevent EMI interference to temperature and pressure signal.
2. What should all metal equipment connect to? Equipotential earthing bar.
3. What power issue accelerates compressor motor aging? Three-phase current unbalance.
4. What standard for export electrical design? IEC standard.
5. What does UPS supply power for? Controller, alarm and gas detector.
6. What load is defrost heater? Large resistive load.
7. What connects to lightning protection system? Outdoor condenser and metal rack frame.
8. What cable performance matters near compressor? Oil resistance and flame retardant.