OMRON G4J Series Solid State Relays & IGBT Modules — G4J-2242T

Technical Dossier

Product Details And Specifications

OMRON G4J Series: Comprehensive Module Range and Technical Overview

The OMRON G4J Series represents one of the most widely deployed families of solid state relays (SSR) and IGBT-based switching modules in global heavy industry. Installed across petrochemical complexes, nuclear power auxiliary systems, offshore refinery platforms, and large-scale chemical processing facilities, the G4J Series established a benchmark for zero-crossing switching, high-cycle-life operation, and DIN-rail-compatible form factors in the 1990s through the 2010s. Its architecture — built around IGBT output stages with optocoupler-isolated control inputs — made it a preferred choice for OEMs integrating Omron PLCs (C200H, CJ1, CS1 families) with high-current AC load control. The G4J-2242T, as a representative member of this series, handles 240VAC load circuits with a 25A rated output current, making it applicable to motor starter auxiliary circuits, heater banks, and solenoid valve arrays in process automation environments.

The Evolution of G4J Architecture

The G4J Series was introduced by OMRON as a successor to earlier electromechanical relay modules, targeting applications where contact wear, arc suppression, and switching speed were limiting factors. Early G4J variants used SCR (thyristor) output stages for AC switching, with zero-crossing detection circuits to minimize EMI at turn-on. As IGBT technology matured through the late 1990s, OMRON transitioned the G4J output stage to IGBT-based designs, enabling faster switching, lower on-state voltage drop, and improved thermal performance under continuous duty cycles.

The G4J Series is compatible with OMRON's G3 and G3NA relay sockets in many configurations, and its control input range (typically 5–24VDC) aligns directly with the output card voltage levels of the C200H, CJ1M, and CS1D PLC families. This cross-compatibility made the G4J a long-lived platform across multiple generations of OMRON control system architecture. By the mid-2010s, OMRON began transitioning customers toward the G3PE and G3PH series for new designs, positioning the G4J as a mature/end-of-life product line. However, the installed base in legacy DCS and relay panel applications remains substantial, sustaining demand for replacement units well into the 2020s.

G4J Full Catalog & Functionalities (SKU List)

The following SKUs represent verified members of the OMRON G4J Series. Each unit is classified by output configuration, load voltage, and rated current:

G4J-2242T: 240VAC, 25A IGBT output SSR, zero-crossing, DIN rail mount
G4J-2242S: 240VAC, 25A SCR output SSR, random-fire switching variant
G4J-2442T: 240VAC, 40A IGBT output SSR, heavy-duty load switching
G4J-2442S: 240VAC, 40A SCR output SSR, phase-angle control compatible
G4J-2222T: 220VAC, 25A IGBT output SSR, compact panel applications
G4J-2422T: 240VAC, 25A IGBT output, screw terminal variant
G4J-1242T: 120VAC, 25A IGBT output SSR, North American market variant
G4J-1442T: 120VAC, 40A IGBT output SSR, high-current 120VAC load control
G4J-2242B: 240VAC, 25A, built-in snubber circuit, inductive load optimized
G4J-2442B: 240VAC, 40A, built-in snubber, motor and transformer load rated
G4J-2262T: 240VAC, 60A IGBT output SSR, large heater bank control
G4J-2262S: 240VAC, 60A SCR output, phase-angle firing for proportional control
G4J-2242T-AC: 240VAC output, AC control input variant (100–240VAC trigger)
G4J-2442T-AC: 240VAC, 40A, AC control input, PLC-independent trigger circuits
G4J-2242T-DC12: 240VAC output, 12VDC control input, sensor-direct switching
G4J-2442T-DC12: 240VAC, 40A, 12VDC control input, field device integration
G4J-2242T-DC5: 240VAC, 25A, 5VDC control input, TTL-level logic compatible

Sourcing Hard-to-Find & Obsolete G4J Series Parts

The G4J Series entered end-of-life status progressively from approximately 2015 onward, with OMRON directing new designs to the G3PE and G3PH families. As a result, OEM channel availability for G4J units has contracted significantly. DriveKNMS maintains a dedicated inventory of G4J Series modules sourced through authorized secondary market channels, including decommissioned panel stock, factory-sealed surplus, and tested pull units from controlled industrial environments.

For operators running legacy OMRON C200H or CS1-based DCS architectures where a full platform migration is not economically viable, DriveKNMS provides lifecycle extension support: unit-level replacement sourcing, cross-reference verification against current OMRON part numbers, and compatibility confirmation against specific relay socket and wiring configurations. All G4J units supplied by DriveKNMS are individually tested prior to dispatch and accompanied by a functional test report.

Quality Control for the G4J Range

IGBT-output solid state relays present specific failure modes that differ from electromechanical relays: IGBT junction degradation under thermal cycling, optocoupler LED current decay reducing input sensitivity over time, and snubber capacitor ESR increase leading to elevated turn-off voltage spikes. DriveKNMS applies a structured test protocol to all G4J units:

Input stage verification: control input threshold voltage measured at 5VDC, 12VDC, and 24VDC reference levels. Output stage load test: resistive load switching at rated current (25A or 40A as applicable) for a minimum of 50 cycles with thermal imaging of the IGBT junction area. Zero-crossing function verification: oscilloscope-confirmed switching at voltage zero-crossing within ±1ms tolerance. Isolation test: 2500VAC dielectric withstand between control input and load output circuits. All units failing any parameter are quarantined and not supplied.