Description
Hard-Numbers: Technical Specifications
- Rated Input Voltage: 24VDC (positive or negative logic)
- Input Voltage Range: 0 to +30VDC
- Inputs per Module: 32 (four groups of eight inputs each)
- Input Current: 7.0mA typical at rated voltage
- On-State Voltage: 11.5 to 30VDC
- Off-State Voltage: 0 to 5VDC
- On-State Current: 3.2mA minimum
- Off-State Current: 1.1mA maximum
- On Response Time: 2ms maximum
- Off Response Time: 2ms maximum
- Backplane Power Draw: 195mA maximum from +5VDC bus
- External Power Draw: 224mA typical from isolated +24VDC supply (all 32 inputs on)
- Isolation Rating (Field-to-Backplane): 250VAC continuous / 1500VAC for 1 minute
- Isolation Rating (Group-to-Group): 50VAC continuous / 500VAC for 1 minute
- Operating Temperature: 0°C to +60°C (+32°F to +140°F)
- Connector Type: Two male 24-pin Fujitsu FCN-365P024-AU connectors
- Hot Swappable: Yes
GE IC694MDL655
The Real-World Problem It Solves
This is the Revision B hardware update of the standard IC694MDL655. Same function, same wiring, same software configuration—just a newer internal component revision. If you’re replacing a failed IC694MDL655, this module drops in without any changes. Emerson uses suffix letters (A, B, C) to track manufacturing revisions; the specs don’t change.
Where you’ll typically find it:
- Replacement spare for existing IC694MDL655 installations
- New builds where the supplier ships the latest revision level
- Inventory standardization when consolidating module versions
Bottom line: Order IC694MDL655B and you get the same module with a newer manufacturing date. No engineering work required.
Hardware Architecture & Under-the-Hood Logic
The IC694MDL655B uses the same architecture as its predecessor: 32 inputs divided into four isolated groups of eight, each with its own common terminal. Input conditioning, optocoupler isolation, and backplane communication are identical to IC694MDL655.
What the “B” revision actually means:
- Component sourcing updates—Emerson may have changed suppliers for passive components or optocouplers.
- PCB manufacturing improvements—trace routing or solder mask updates for reliability.
- No functional changes—firmware compatibility, I/O addressing, and response times remain the same.
- Full backward compatibility—the module identifies itself to the CPU identically to the base model.
GE IC694MDL655
Field Service Pitfalls: What Rookies Get Wrong
Confusing Hardware Revision with Functional VariantThe “B” suffix is not a different model—it’s a manufacturing revision. Some technicians assume Revision B means faster response or different specs. It doesn’t. The module behaves identically to IC694MDL655 in every way that matters for programming and wiring.
- Field Rule: Treat IC694MDL655B as a direct replacement for IC694MDL655. No ladder logic changes, no hardware configuration updates, no wiring modifications.
Assuming Revision B Has Enhanced DiagnosticsSome newer RX3i modules offer advanced diagnostics. This is not one of them. Like the base , Revision B reports no special fault or alarm diagnostics beyond basic input state. If you need channel-level diagnostics, you’re looking at the wrong module family.
- Quick Fix: For applications requiring wire-break detection or input diagnostics, consider the IC695 series enhanced I/O modules instead.
Not Updating Spare Parts DocumentationIf your maintenance system tracks specific part numbers, IC694MDL655B may not appear in your approved spares list even though it’s functionally identical. This can cause procurement delays or confusion during emergency replacements.
- Field Rule: Update your spares inventory system to accept both and IC694MDL655B as valid substitutes. They’re the same part with different revision stamps.
Commercial Availability & Pricing Note
Please note: The listed price is for reference only and is not binding. Final pricing and terms are subject to negotiation based on current market conditions and availability.
