• Power supply: Main supply-Standard 220-230V, 3 phase, 50 Hz (TN-S) electric power shall be supplied to the main distribution board (Dirty supply). The sites are equipped with redundant power supply system (Clean supply)  comprising 2 diesel generators, operating in 1+1 redundancy, 2 independent UPS systems 230V or 48VDC rectifier systems “ELTEK”, operating in 1+1 configuration (A+B). The cable routes and power distribution boards of A and B systems are fully diversed one from another. Each cabinet will be supplied via 2 diverse routes between fuse bus and cabinet socket.

For avoiding of doubts the power supply must conform to the following:

230/400 V AC according to PN-IEC 60038

48 V DC 45V<E<55V

Power supply system is designed in a way that every rack will have 11kW of AC power (3 phases, 16 A breaker) from 2 fully diverse sources (A+B). DC 48 V is available in 25A, 50 A. 63 A. 80 A or custom, thus providing from 1200 W to 4000 W or more, if needed. Like AC, here the supply is from 2 different sources, where each can supply nominal power.

For AI applications a new 800 V DC system is designed and will be implemented soon.

Each site is connected to utility power via 2 diverse routes. In case of a loss of utility power a diesel geenrator will start within 30 s and the load will be automatically trasfered by means of ATS (Automatic Transfer Switch) to diesek generator. Each diesel generator is fueled for 24 hours under nominal load. Mobile generator is available and can be delivered on site within 2 hours.

During switchover the power supply to IT equipment is maintained by UPS (Uninterruptible Power Supply) systems in 1+1 configuration. Each UPS system can provide independently the full powerm necessary to supply the IT load. UPS system use batteries to store energy and use it in case of power loss. All our UPS systems operate in double conversion mode, thus filtering any spikes and interruptions in the input power)

• We use lead-acid sealed batteries CSB Hitachi or Monbat

The batteries on 48V DC system will ensure at least 8 hours of operation for each (A and B) systems, under nominal load. The UPS systems will provide at least 20 min. of operation each.

• Grounding: The protective grounding contour will have less than 5 ohms resistance. A separate lightning protection grounding and telecom grounding contours are installed. A proper bonding between contours ensures that no overvoltage sill occure.

• Surge Protection-for protection against surges caused by direct lightning strikes or remote lightning strikes and switching operations a system of arresters and surge protectors are installed in the main distribution board and sub-distributor.