Protection Relays and Controls
GROUND-FAULT PROTECTION – UNGROUNDED AC SYSTEMS
PGR-3100 Series
Ground-Fault Indication System
Description
The PGR-3100 indicates the presence of voltage on each
phase of a three-phase system. The LEDs on the panel
illuminate when voltage is present. When a ground-fault
occurs, the voltage on the faulted phase reduces to ground
potential, causing the LEDs for the faulted phase to dim
and the LEDs for the unfaulted phases to become brighter.
Ungrounded ac systems are required by the National
Electrical Code (NEC®) Article 250.21(B) and the Canadian
Electrical Code Part 1, Section 10-106 (2) to have ground
detectors, such as the PGR-3100, installed on the system.
External potential transformers (PTs) can be used to step
down system voltage, allowing the PGR-3100 to be applied
to any system voltage. PTs are not required for system
voltages up to 600 V ac.
Simplified Circuit Diagram
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Features & Benefits
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FEATURES
BENEFITS
Meets National Electrical Code (NEC) Article
250.21(B) and Canadian Electrical Code Part 1,
Section 10-106 (2) requirements for ungrounded
systems
NEC® and CE Code
compliant
Indicates presence of a ground fault and the
faulted phase as well as phase-to-ground
voltage on an energized bus
Phase LEDs
PGR-3100
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Redundant long-life LEDs (two per phase) to
ensure reliability
Redundant LEDs
Lamp test button
Verifies LEDs are operating
Specifications
Input Voltage
Indicator Off Voltage
Dimensions
Up to 600 V ac 50/60 Hz
< 30 V ac line to ground
Ordering Information
ORDERING NUMBER
MOUNTING
H 88.9 mm (3.5”);
W 108 mm (4.3”);
D 54 mm (2.1”)
PGR-3100
Panel mount
Test Button
Approvals
Conformally Coated
Warranty
Local
CSA certified, UL Listed
Standard feature
5 years
Mounting
Panel
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products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at www.littelfuse.com/product-disclaimer.
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