

The Industrial Shock Block® SB5000 series is a personnel protection device designed to meet the requirements for special- purpose GFCIs defined by UL 943C. This standard outlines GFCI classes specifically designed for use in industrial facilities. 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. The SB5000 includes DFT harmonic filtering, an automatic self-test feature, and is compliant to the UL 1998 Software in Programmable Components standard.
Ground-Fault Circuit Interrupter (GFCI), Class AThe SB5000 is available as a 208 or 240 V Class A GFCI, allowing commercial kitchens, vehicle service centers, and other non-dwelling applications to meet NEC 210.8(B) for their three-phase loads up to 100 A.
Equipment Ground-Fault Protective Device (EGFPD)The SB5000 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 and SPGFCI devices are not permitted to have an adjustable trip level.
Ratings & ModelsThe SB5000 is available for three-phase voltages from 208 to 600 V with a maximum full load current up to 100 A. The power system can be either solidly or high-resistance grounded, and the load must be single-phase or three-phase as long as the load does not require a neutral. The standard enclosure is IP 69K/NEMA 4X and outdoor rated, suitable for all industrial environments including high temperature washdown used in food production applications. The 32 and 60A models are also available in a hygienic stainless steel enclosure, with a 10 degree sloped top and FDA compliant silicone gasket, designed to facilitate sanitation in food processing facilities and the like.
Grounding Monitor / Interrupter (GMI)The SB5000 also monitors the equipment grounding connection between the Shock Block and load. This is a required feature for Class C and D GFCI devices and is recommended for Class A GFCI and EGFPD devices. If the ground-return path is broken, the SB5000 will trip and provide an alarm by changing the state of the alarm contacts. This monitoring circuit requires an extra (pilot) wire between the SB5000 and the load. At the load, the pilot wire is connected to a termination device. The other end of the termination device is connected to the equipment ground (typically the enclosure).
- UL 943 inverse time trip curve
- DFT (Discrete Fourier Transform) filtering algorithm
- Minimum trip time <20 msec
- Fixed 6 mA (UL 943) or 20 mA (UL 943C) trip level
- Selectable trip levels 6–100 mA
- Two-stage ground monitor with Zener termination that meets UL 943C, CSA M421
- Flexible configuration
- Conformal coating
- Auxiliary contact
- Automatic self-test
- Inverse time detection circuit protects people while also reducing the probability of nuisance tripping
- Eliminates nuisance trips due to harmonics
- Reduces the risk of ventricular fibrillation for leakage current of 250 mA and above
- UL Listed GFCI and Special-Purpose GFCI personnel protection for industrial and commercial loads up to 100 A (GFCI versions)
- Settings below 20 mA provide extra safety. The settings above 20 mA can reduce nuisance tripping on systems with high-leakage current (EGFPD versions)
- Proactively protects from shock by tripping if continuity of ground wire between Industrial Shock Block and load is broken
- Selectable manual reset or auto-reset for brownout, power-up, and ground monitor interruptions to fit plant safety protocols
- Internal PWB is conformally coated to protect against corrosion and moisture
- Alerts your SCADA system if the Shock Block is energized or tripped
- The Shock Block will continuously test itself and will trip if there is an internal failure
SB5000 Parts
Filters
Part Number | Actions | Conformally Coated | Frequency (Hz) | GF Trip Level A | NEMA Rating | Relay Contacts Config | Relay Contacts Operation | System Type | Supply Voltage AC |
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Part Number | Actions | Conformally Coated | Frequency (Hz) | GF Trip Level A | NEMA Rating | Relay Contacts Config | Relay Contacts Operation | System Type | Supply Voltage AC | |
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SB5000 Applications
- For applications where people, electrical equipment, and water are present
- Wastewater facilities
- Food and beverage
- Commercial kitchens
- Amusement parks
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SB5000 Support
Frequently Asked Questions
What is UL 943C and how does it differ from UL 943?
UL Standard 943 applies to Class A, single- and three-phase, Ground-Fault Circuit Interrupters (GFCI) intended for protection of personnel, for use only in grounded neutral systems in accordance with the National Electrical Code (NEC®), ANSI/NFPA 70, and the Canadian Electrical Code, C22.1 (CEC), These devices are intended for use on alternating current (AC) circuits
What are the different UL GFCI Classes?
Class A – A GFCI that will interrupt the circuit to the load when the ground-fault current is 6 mA or more but not when the ground-fault current is 4 mA or less and is intended to be used in circuits where the line-to-line voltage is 240 V or less. Class B – A GFCI that will interrupt the circuit to the load when the ground-fault current exceeds 20 mA. Only used with
What does the Shock Block do?
The Shock Block detects leakage current and interrupts the circuit significantly reducing or eliminating the shock potential. One key part of the additional safety features mentioned earlier, is that the Shock Block also monitors the ground wire from the unit to the load for continuity. If the wire is broken or becomes loose, the Shock Block will signal an alarm and