Component Snapshot At-a-Glance
- Model: KJ4002X1-BC1
- Alt. P/N: 12P1729X042
- Product Series: DeltaV M-Series Standard I/O System
- Hardware Type: Passive 4-slot vertical I/O carrier backplane
- Key Feature: Interlocking flat ribbon bus for multi-carrier rack expansion, no onboard power regulation circuitry
- Primary Field Use: Houses up to four DeltaV I/O modules and corresponding field terminal bases, distributes backplane power and LocalBus data across control racks
Hard-Numbers: Technical Specifications
- Slot Capacity: 4 independent module mounting positions per single carrier
- Protocol Support: DeltaV proprietary LocalBus backplane communication
- Input Power Source: Fed externally from KJ4003X1-BC1 master power carrier
- Distributed Rails: 12VDC logic, 5VDC, 3.3VDC backplane supply
- Operating Temperature: -40°C to +70°C ambient cabinet rating
- Isolation Rating: No internal circuit isolation; channel isolation handled by paired I/O modules
- Mount Standard: EN 60715 35mm DIN rail snap-in installation
- Vibration Rating: 0.7g @ 2–150Hz per ISA-S71.04 G3
- Weight: 0.41kg nominal
- Certifications: Class I Div 2, ATEX II 3G, UL/CSA listed
The Real-World Problem It Solves
Custom fabricated aluminum rack frames require custom drilling and inconsistent spacing, leading to misaligned card seating and intermittent LocalBus dropouts in corrosive plant cabinets. Older fixed-size backplanes limited incremental I/O expansion without full rack replacement.
Where you’ll typically find it:
- Refinery distillation unit DCS marshalling cabinets populated with HART AI/DO modules
- Coal-fired power plant boiler feedwater control I/O racks
- Chemical plant reactor utility skid control enclosures
It lets technicians build modular expandable racks with standardized spacing and pre-routed backplane bus paths to cut field fabrication labor.
Hardware Architecture & Under-the-Hood Logic
This unit is fully passive with zero embedded microprocessors or active components; stamped copper traces route power and LocalBus between slots and adjacent chained carriers.
- Master power carrier (KJ4003X1-BC1) feeds regulated multi-voltage power into first carrier via interlocking flat ribbon cable.
- Internal copper bus traces split incoming power evenly across all four card slots on the carrier.
- Separate isolated trace paths carry DeltaV LocalBus communication signals between every slot position.
- Edge gold contacts on bottom side mate mechanically with KJ4001-series terminal base upper connectors.
- Extra ribbon header on end edge enables daisy-chain connection to additional carriers for rack expansion.
Field Service Pitfalls: What Rookies Get Wrong
Improper Ribbon Bus Connection Between Cascaded Carriers
New technicians force ribbon cable pins or leave inter-carrier connectors partially unseated during rack build. Partial contact causes random single-slot I/O dropout or full carrier offline with steady module FAULT indication.
- Field Rule: Seat ribbon connectors straight until full positive click; route cables with minimum 50mm bend radius to avoid pin pullback from thermal cabinet cycling.
Mismatched Terminal Base to Carrier Notch Coding
Installers force wrong key-coded KJ4001 terminal bases into carrier slots, damaging carrier plastic notch tabs and gold edge traces over repeated insertions.
- Quick Fix: Match mechanical coding key between base and slot before insertion; replace cracked carrier if plastic locating tabs break off completely.
Overcrowding DIN Rail With Poor Airflow Clearance
Techs stack multiple carriers back-to-back with less than 15mm vertical gap between racks. Heat buildup inside enclosed cabinets accelerates trace oxidation and creates intermittent high-resistance faults.
- Field Rule: Maintain minimum 20mm vertical free space above and below carrier banks for convection cooling per DeltaV cabinet layout specs.
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.
