Toshiba 300 KW External Breakers, Grounding Wire, Be sure to ground the UPS as specified

11.4External Breakers

The G8000 UPS units are not equipped with circuit breakers. Qualified personnel should provide the external breakers for the AC input/output, bypass input and DC input.

See Figure 11.1 – External Wiring Diagram, for the circuit position of the breakers.

Table 11.6 shows the G8000 UPS minimum external breaker rating for each capacity. The bypass input and the AC output require 3-pole breakers.

	TABLE 11.6 EXTERNAL BREAKER RATING
Capacity	AC Input / Bypass Input / AC Output	DC Input
	Minimum Breaker Rating	Minimum Breaker Rating
100 kVA	480 V - 200 A	500 VDC – 500 A
150 kVA	480 V - 300 A	500 VDC – 700 A
225 kVA	480 V - 450 A	500 VDC – 1100 A
300 kVA	480 V - 500 A	500 VDC – 1500 A

11.5Grounding Wire

WARNING

Be sure to ground the UPS as specified.

Using the UPS without a proper ground will deteriorate the insulation, cause leakage of currents and electric shock.The resistance to ground should be less than or equal to 10 ohms.

The 100/150/225kVA earth grounding bus is located inside, at the bottom-front of the unit. The 300 kVA earth grounding bus is located inside, at the top-left of the unit.

Use a AWG 2 (or 38 mm2) or larger cable for the grounding wire. Run the grounding wire through the opening at the bottom, or through a hole in the top knockout plate (if available). See Figure 11.10. Connect either the top or bottom earth ground bus, but not both, to the grounding wire.

The ground wire must have a crimp terminal with a 1/2 in. (12 mm) diameter bolt hole. The ground bus has 33/64 in. (13 mm) bolt hole. The connect the crimp terminal and ground bus together using a 7/16 in. (10 mm) diameter bolt.

36 G8000 Series Installation and Operation Manual