Littelfuse's SB6100 Industrial Shock-Block meets UL 943C Class C and Class D requirements
Littelfuse's SB6100 Series Industrial Shock-Block is a ground fault circuit interrupter (GFCI) device that is built to meet UL 943C Class C and Class D requirements. GFCI devices operate by sensing a ground fault and opening the circuit very quickly. However, residential GFCI devices are too sensitive to operate in industrial applications without nuisance tripping. The UL 943C standard covers such GFCI devices, designed to be used with systems up to 600V and higher leakage current higher than residential GFCI devices
Industrial GFCI devices have a set 20mA trip level, which is set by the UL943 standard. Equipment ground fault protection devices (EGFPD) have the same functionality as a GFCI but offer adjustable trip settings from 6mA to 30mA for added flexibility. Both models have voltage ratings range from 208 to 600 V and are rated at 100 A.
Littelfuse added several safety features, including monitoring the integrity of the ground wire to ensure a return path for leakage current. If the wire is broken or becomes loose, the Littelfuse Shock-Block GFCI will signal an alarm and interrupt power.
Even though UL requires a minimum short circuit current rating of 5,000 A, the Shock-Block GFCI device is tested up to 50,000 A.
In addition, the SB6100 Shock-Block GFCI goes beyond the UL standards by including built-in overcurrent protection supplied by Littelfuse Class T fuses. The SB6100 Shock-Block GFCI is available as an open-chassis unit that is UL-recognized for installation by an OEM, or as an enclosed unit with a NEMA-4X UL-listed enclosure.