Specification

Corner-Grounded Delta (Grounded B Phase) Systems 2700DB0202R03/12

References 09/2012

Electrical equipment should be installed, operated, serviced, and maintained only by

qualified personnel. No responsibility is assumed by Schneider Electric for any

consequences arising out of the use of this material.

I-Line™, Square D™, and Schneider Electric™ are trademarks or registered

trademarks of Schneider Electric. Other trademarks used herein are the property of

their respective owners.

Schneider Electric USA, Inc.

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ENGLISH

Switchboards QED custom switchboards are UL Listed for use on grounded B phase

systems when properly rated devices are installed (see the “Devices”

section beginning on page 5 for details). QED switchboards can be rated up

to 480 Vac as shown in Table 8.

References • IEEE Standard 142, 2007: “IEEE Recommended Practice for Grounding

of Industrial and Commercial Power Systems”

• IEEE Standard 241, 1990: “IEEE Recommended Practice for Electric

Power Systems in Commercial Buildings”

• National Electrical Code, 2011

• NEMA Standards: Publication No. PB 1-2011

• NEMA Standards: Publication No. PB 2-2011

• Underwriters Laboratories Standard 67, 2010

• Underwriters Laboratories Standard 891, 2005

• Underwriters Laboratories Standard 489, 2011

Table 8: Switchboard Voltages

Type of Switchboard Grounded B Phase System Rating

Circuit breaker switchboards 240 Vac, 480 Vac

Fusible switchboards 240 Vac, 480 Vac