SB6100 Series Ground-Fault Circuit Interrupter

Special-Purpose Ground-Fault Circuit Interrupter (GFCI),

Class C and Class D

Industrial Shock Block (ISB) is a personnel protection device designed to

meet the new requirements for special-purpose GFCIs defined by UL 943C.

ISB is the first permanently connected Class C and Class D GFCI on the

market. Class C GFCIs are intended to be used on three-phase systems

where the line-to-line voltage is 480 V or less with a trip level of 20 mA,

while Class D GFCIs are intended to be used on 600 V systems. These

improvements to the standard Class A GFCI (6 mA trip level used on 240 V

systems or less) were made to allow the use of GFCIs in industrial facilities.

The ISB includes an automatic self-test feature and is compliant to the

UL1998 Software in Programmable Components standard.

Equipment Ground-Fault Protective Device (EGFPD)

ISB is also available with adjustable protection settings as an EGFPD. The

EGFPD models can be set to trip at 6 mA or from 10-100 mA in increments

of 10 mA. This offers more flexibility since GFCI devices are not allowed to

have an adjustable trip level.

Rating and Models

ISB (GFCI & EGFPD) is available for three-phase voltages from 208 to 600

V with a maximum full load current of 100 A, and a built-in overcurrent

protection supplied by Littelfuse Class T fuses. The load must be 3-phase,

however, cannot have a neutral. The power system can either be solidlygrounded

or high-resistance grounded.

Two options for enclosures are available: UL-recognized open-chassis models

are available for installation in existing electrical enclosures and UL-listed

enclosed models include a NEMA-4X enclosure for stand-alone installations.

Ground Wire (Load-Ground) Monitor

The ISB also monitors the ground wire (load-ground) connection between the

ISB and load. This is a required feature for GFCI devices and is optional for

EGFPD devices. If the connection is broken, the ISB will provide an alarm by

changing the state of the alarm contacts. This monitoring circuit includes an

extra wire (pilot wire) between the ISB and load (since the monitoring current

is low, only a small wire is required). At the load, the pilot wire is connected to

a termination device. The other end of the termination device is connected to

the load ground (typically the enclosure).