Honeywell 2MLI-D21A-CC Digital Input Module | Replacement, Equivalent & Selection Guide
The Honeywell 2MLI-D21A-CC is a high-reliability Digital Input Module designed for use in Honeywell’s Experion PKS and TDC 3000 Distributed Control Systems (DCS). This module provides discrete signal acquisition from field devices, enabling precise process monitoring and control in demanding industrial environments. Konmask.com supplies both genuine OEM units and verified compatible replacements to keep your automation system running without interruption.
Technical Specifications
- Part Number: 2MLI-D21A-CC
- Manufacturer: Honeywell Process Solutions
- Module Type: Digital Input (DI)
- Compatible Platform: Honeywell Experion PKS, TDC 3000, PlantScape
- Input Channels: 32-channel discrete input
- Signal Type: Dry contact / Wet contact (24 VDC)
- Communication: Backplane bus interface
- Isolation: Optical isolation per channel group
- Operating Temperature: 0°C to 60°C
- Power Supply: Supplied via DCS backplane
- Mounting: Card cage / rack-mount
- Certifications: CE, UL (refer to OEM datasheet for full listing)
- Weight: ~250 g
Compatible Replacement & Equivalent Models
If the 2MLI-D21A-CC is discontinued, out of stock, or cost-prohibitive, the following models may serve as functional equivalents depending on your system configuration. Always verify firmware and backplane compatibility before substitution.
- Honeywell 2MLI-D21B-CC – Revised revision of the same module family; pin-compatible in most Experion PKS racks
- Honeywell MC-PDID03 – Digital Input module for C300 controller series; requires adapter for legacy TDC racks
- Honeywell 51304485-150 – DI module used in TDC 3000 HPM; functionally similar channel count
- Honeywell 51309276-175 – Digital Input card for PM/APM subsystems; verify slot compatibility
- Third-party compatible: Contact Konmask.com for vetted cross-reference options with full test reports
Disclaimer: Cross-reference data is provided for reference only. Konmask.com recommends engineering validation before field deployment of any replacement module.
Why Choose the Original Model
- Guaranteed OEM compatibility – No firmware conflicts or backplane mismatch risk
- Proven field reliability – Validated in continuous 24/7 process environments
- Honeywell support coverage – Eligible for OEM technical support and warranty
- Regulatory compliance – Meets SIL and functional safety requirements as originally certified
- Seamless hot-swap – Designed for live replacement in redundant DCS architectures
Typical Applications
- Oil & gas upstream/downstream process control
- Chemical and petrochemical plant automation
- Power generation and utilities monitoring
- Pharmaceutical batch process control
- Pulp & paper and water treatment facilities
- Any Honeywell Experion PKS or TDC 3000 installation requiring discrete input acquisition
System Compatibility
| DCS Platform | Compatible | Notes |
|---|---|---|
| Honeywell Experion PKS | Yes | Primary target platform |
| Honeywell TDC 3000 | Yes | Verify rack slot assignment |
| Honeywell PlantScape | Partial | Confirm firmware version |
| Honeywell Safety Manager | No | Use SIL-rated DI modules |
| Third-party DCS | No | Not designed for cross-platform use |
Selection Guide
- Step 1 – Identify your DCS platform: Confirm you are running Experion PKS or TDC 3000.
- Step 2 – Count required DI channels: This module supports 32 discrete inputs; size your rack accordingly.
- Step 3 – Verify signal voltage: Confirm field devices output 24 VDC dry/wet contact signals.
- Step 4 – Check rack slot type: Ensure the target slot accepts the 2MLI card form factor.
- Step 5 – Confirm revision level: Match the -CC revision suffix to your existing installed base for consistency.
- Step 6 – Evaluate redundancy needs: For critical loops, consider pairing with a redundant DI module.
Quality Assurance & Sourcing
- Inspection: All units undergo visual, functional, and communication interface testing before shipment
- Packaging: ESD-safe anti-static packaging with moisture barrier
- Documentation: Certificate of conformance and test report available on request
- Source: Sourced from authorized distributors, OEM overstock, and certified refurbishers
- Warranty: 12-month replacement warranty on all units supplied by Konmask.com
How to Order
- Add the Honeywell 2MLI-D21A-CC to your cart on this page
- Or contact us directly with your PO or RFQ:
- Email: support@konmask.com
- Phone/WhatsApp: +0086 19859288691
- Website: https://Konmask.com
We respond to all inquiries within 1 business day. Bulk pricing and expedited shipping available.
Replacement & Compatibility FAQ
Q: Is the 2MLI-D21A-CC still in production?
A: This module may be in limited production or end-of-life status. Konmask.com maintains stock of both new and refurbished units. Contact us for current availability.
Q: Can I use a 2MLI-D21B-CC as a direct replacement?
A: In most cases yes, but verify the revision change log with Honeywell engineering or your system integrator before swapping in a live system.
Q: Do you provide a test report with each unit?
A: Yes. A functional test report is available upon request for all units shipped from Konmask.com.
Q: What is the lead time?
A: In-stock units ship within 2-5 business days. Out-of-stock items typically have a 2-4 week lead time. Contact us for real-time availability.
Q: Can Konmask.com source obsolete Honeywell DCS modules?
A: Yes. We specialize in legacy and obsolete DCS/PLC parts. Submit your part number and we will respond with availability and pricing.
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Original Source: https://Konmask.com
Contact: support@konmask.com | +0086 19859288691
