Description
Key Technical Specifications
- Model Number: CC-UDIR01
- Manufacturer: Honeywell Process Solutions
- Input Channels: 8 independent relay-isolated digital inputs
- Input Signal Compatibility: Dry contacts, 24–250V AC (50/60Hz), 24–250V DC
- Isolation Rating: 2500V AC channel-to-backplane; 500V AC channel-to-channel (1-minute dielectric test)
- Status Indicators: Per-channel green LED (illuminates when input is energized/contact is closed)
- Power Supply: 24VDC dual redundant inputs (18–32VDC operating range), 0.3A max total current draw
- Hot-Swap Capability: Yes (supports replacement without Experion PKS controller shutdown)
- Operating Temperature: -20°C to +60°C (-4°F to +140°F)
- Storage Temperature: -40°C to +85°C (-40°F to +185°F)
- Mounting Type: Rack-mounted (fits Experion PKS C-Series I/O chassis)
- Diagnostic Capabilities: Open-circuit detection, power supply fault monitoring, backplane communication diagnostics
- Certifications: UL 508, CSA C22.2 No. 142, CE, ATEX Zone 2 compliant
Honeywell CC-UDIR01
Field Application & Problem Solved
In refineries, chemical plants, and power generation facilities running Experion PKS, the biggest headache with digital input modules is compatibility with mixed signal types. Legacy DI modules force technicians to stock separate units for AC, DC, and dry contact signals— a logistical nightmare that increases spare parts costs and installation time. The CC-UDIR01 solves this with universal input capability: it accepts 24–250V AC/DC and dry contact signals on the same module, eliminating the need for multiple module types in the I/O rack.
You’ll typically find this module in safety-critical loops where high-voltage isolation is non-negotiable— think boiler flame detection systems, ESD valve position sensing, and turbine vibration switch monitoring. It’s also a go-to choice for retrofits, because it drops into existing C-Series I/O racks without rewiring or controller reconfiguration. Its core value is relay isolation: unlike optocoupler-isolated modules, the CC-UDIR01 uses physical relays to separate field signals from the controller logic, providing superior protection against high-voltage surges and EMI. I’ve seen this module survive a lightning strike that fried three optocoupler-based DI modules in the same rack— a testament to its rugged design.
Another hidden value is its diagnostic transparency. The per-channel LEDs and Experion PKS-integrated diagnostics let technicians distinguish between a tripped field switch and a wiring fault in seconds, cutting troubleshooting time from hours to minutes. For maintenance teams, this means fewer unplanned shutdowns and more time spent on proactive tasks instead of chasing false alarms.
Installation & Maintenance Pitfalls (Expert Tips)
Relay Coil Polarity Doesn’t Matter— But Wiring Does: Rookies waste hours checking polarity for DC inputs, but the CC-UDIR01’s relays are polarity-insensitive. What does matter is ensuring the input signal falls within the 24–250V range— feeding it 300V AC will burn out the relay contacts, and the damage won’t show up immediately. Always verify the field device’s output voltage with a multimeter before wiring, even if the schematic says 120V AC. I’ve fixed two fried modules in a month because a tech skipped this step.
LED Indicators Are Your First Line of Defense: The green per-channel LEDs aren’t just for show— they confirm the relay has actuated, independent of the controller. If the LED is on but the HMI says the input is inactive, the problem is in the backplane or controller configuration. If the LED is off but the field device is tripped, the issue is in the wiring or the device itself. Too many techs skip checking the LEDs and waste hours troubleshooting the controller when the problem is a loose terminal. Make this a first-step check in your diagnostic process.
Hot-Swap Requires Controller Configuration First: The module is hot-swappable, but only if you enable the “hot-swap” flag in Experion PKS Configuration Studio. Yanking an unconfigured module will trigger a rack communication fault and may cause the controller to fault associated safety loops. Before replacement, mark the module as hot-swappable and set the input loops to “hold last state” during the swap. I’ve seen a tech take down a reactor control loop by ignoring this step— don’t repeat the mistake.
Don’t Skimp on Terminal Torque: The module uses screw terminals for field wiring, and loose terminals cause arcing, corrosion, and intermittent input signals. Use a torque screwdriver set to 0.5 N·m to tighten the terminals— over-tightening strips the threads, under-tightening causes loose connections. In corrosive environments (like coastal refineries), apply a thin layer of anti-corrosion grease to the terminals after wiring to prevent rust buildup that leads to signal loss.
Honeywell CC-UDIR01
Technical Deep Dive & Overview
The Honeywell CC-UDIR01 is a relay-isolated universal digital input module designed for Experion PKS C-Series I/O racks, built to handle the mixed signal types and high-voltage surges common in industrial environments. At its core, each of the 8 channels uses a heavy-duty electromechanical relay to isolate the field signal from the module’s logic circuit— a critical difference from optocoupler-isolated modules. This relay isolation provides 2500V AC protection against high-voltage transients, making the module ideal for safety-critical loops where controller damage could lead to catastrophic process upsets.
The module’s universal input design means it can accept dry contact, AC, or DC signals without configuration— the relay actuates whenever the input exceeds the minimum threshold (24V AC/DC), simplifying installation and reducing human error. The per-channel LEDs are hardwired to the relay contacts, providing real-time input status that’s independent of controller communication— a lifesaver when the network is down or the controller is faulty.
Powered by dual redundant 24VDC inputs, the module switches seamlessly between primary and secondary supplies in less than 1ms, ensuring uninterrupted operation during power glitches. When hot-swapped, it auto-syncs with the Experion PKS controller and restores input loop parameters without manual intervention. Unlike smart modules with complex firmware, the CC-UDIR01 has no user-programmable settings— it’s a “plug-and-play” device that’s recognized automatically by the controller, reducing the risk of misconfiguration.
In the field, this module’s strength is its durability. The relay contacts are rated for 100,000+ operations, and the rugged construction withstands vibration, temperature swings, and corrosion that would take down cheaper modules. With proper installation, it runs for 10+ years without unplanned failures, making it a favorite among maintenance teams who value reliability over fancy features. For Experion PKS users, it’s the go-to digital input module for any application where mixed signal compatibility and high isolation are non-negotiable.
