GE IC693MDL940H Isolated Relay Output Module (NO contacts)

Description

What This Product Solves

In Series 90-30 PLC-based industrial automation and process control systems, connecting outputs to field devices that operate across varying voltages, separate power sources, or require complete electrical isolation frequently creates headaches. Solid-state modules can introduce ground loops, limit voltage flexibility, or necessitate extra interposing relays when switching AC loads, DC solenoids, or mixed-voltage actuators, leading to increased panel space, higher costs, potential noise issues, or compromised safety in interlocked systems.

GE IC693MDL940H directly tackles these problems as a 16-point isolated relay output module with normally open (NO) dry contacts, offering full galvanic separation between the PLC logic and field circuits. This isolation becomes critical in environments with diverse power domains—such as 120/240 VAC motor starters alongside 24 VDC indicators—or where ground potential differences exist between control cabinets and remote equipment.

GE IC693MDL940H provides the versatility to handle up to 2 A per point (4 A per common) across a broad range of AC (5–250 V) and DC (5–30 V) loads without external converters or relays in most applications. For engineers dealing with multi-vendor integrations, legacy expansions, or safety-related outputs, this module reduces wiring complexity, eliminates many common electrical interference risks, and supports reliable discrete actuation that maintains system stability and simplifies compliance in noisy or electrically segmented industrial setups.

How the Product Works & Fits into a System

GE IC693MDL940H functions as a 16-channel electromechanical relay output module in the GE Fanuc (now Emerson) Series 90-30 PLC family, using SPST-NO dry contacts to switch user-supplied power to field devices. It plugs into any available I/O slot on a baseplate or expansion rack, with field wiring connected through a removable terminal block divided into four isolated groups of four outputs each (one common per group for flexible power routing).

In the automation architecture, GE IC693MDL940H sits in the discrete output layer, receiving on/off signals from the PLC CPU via the backplane to energize the relay coils (powered by the 24 V DC backplane bus). When activated, the relay closes the contact, passing the external AC or DC supply to the load. Each point includes an LED indicator that illuminates when the relay is closed, providing straightforward visual status during operation or diagnostics.

With robust isolation (1500 V field-to-logic, 500 V group-to-group), GE IC693MDL940H allows independent voltage sources and grounds per group, preventing cross-talk or transients from affecting the PLC. Response times hover around 15 ms, suitable for general-purpose control. GE IC693MDL940H pairs naturally with input modules or other I/O types in the Series 90-30 ecosystem, delivering a flexible, isolated interface for centralized or distributed discrete control where voltage diversity or safety isolation is paramount.

Technical Highlights Summary

Real-World Benefits

GE IC693MDL940H excels at providing true electrical separation and broad compatibility, engineered to switch mixed AC/DC loads reliably without risking PLC damage from voltage mismatches or inductive kickback. The group-isolated commons and dry contacts simplify connections to devices from different vendors or power systems, cutting down on auxiliary hardware and reducing potential points of failure in the field wiring.

Maintenance teams benefit from intuitive LED feedback per point and easy terminal access, accelerating fault diagnosis and minimizing downtime during inspections or modifications. Over extended deployments, GE IC693MDL940H helps extend the usability of Series 90-30 platforms by enabling seamless additions of isolated outputs, lowering total system costs through fewer external components, and ensuring dependable performance that supports stable operations in electrically challenging industrial environments.

Typical Use Cases

GE IC693MDL940H is a go-to choice in Series 90-30 setups needing isolated, multi-voltage discrete outputs. In manufacturing and automotive plants, it controls motor contactors, solenoid valves, or safety interlocks across assembly lines where 120/240 VAC power coexists with 24 VDC signaling, providing the isolation needed for noise-prone or distributed layouts.

Process facilities in chemicals, pharmaceuticals, or food & beverage rely on GE IC693MDL940H to actuate valve actuators, alarm buzzers, or pump starters in panel-based or skid-mounted systems, where separate power domains and ground isolation prevent interference in sensitive or hazardous areas. In material handling and packaging applications, the module drives diverter gates, conveyor motors, or indicator arrays under continuous duty, ensuring critical system uptime in process control environments with vibration, dust, and potential electrical transients.

Compatible or Alternative Products

• IC693MDL940 – Base or earlier revision version, functionally equivalent in most applications
• IC693MDL930 – 8-point relay output module for applications needing fewer channels
• IC693MDL740 – 16-point 12/24 V DC sourcing solid-state output for non-isolated DC-only loads
• IC693MDL742 – 16-point 12/24 V DC sourcing solid-state output with higher current rating
• IC693MDL645 – Matching 16-point 24 V DC input module for balanced discrete I/O setups
• IC693MDL646 – High-speed input counterpart for time-critical input/output pairs
• IC694MDL940 – Equivalent relay output in the RX3i platform for migration paths
• IC695 series relay modules – Advanced RX3i options for future system upgrades

Setup Notes & Maintenance Insights

Before installing GE IC693MDL940H, verify rack slot availability and backplane power sufficiency for the relay coil load (typically low but cumulative in dense racks). Supply field power externally per group—matching voltage and fusing appropriately—and wire loads with suppression (diodes for DC, snubbers/MOVs for AC) to protect contacts from inductive spikes. During startup, force %Q bits selectively in the programmer to confirm LED response and load actuation, ensuring no cross-group interference.

Routine maintenance includes checking LEDs for proper on/off indication during normal runs—any discrepancy may point to relay wear or field issues. Inspect terminals yearly for tightness, arcing marks, or corrosion, especially in high-cycle or aggressive atmospheres. Periodically test relay operation by forcing outputs and verifying field response; track cycle counts in demanding applications as mechanical relays have finite life. These steps keep GE IC693MDL940H performing reliably with practical oversight.