Emerson KJ4002X1-BF2 (12P3866X012) DeltaV M-series Bottom Extender Cable Assembly

Product Overview

The Emerson KJ4002X1-BF2 (alternatively identified by part number 12P3866X012) is a 1.2-meter, 44-pin Bottom Extender Cable Assembly specifically designed for the DeltaV™ M-series I/O Subsystem. This hardware component facilitates the expansion of the LocalBus between horizontal carriers, allowing for flexible physical layouts within DCS (Distributed Control System) cabinets. It is engineered to carry high-current LocalBus circuit power (12.6 VDC at 15 A) and high-speed communication signals across carrier segments.

Designed for demanding industrial environments, the KJ4002X1-BF2 is rated for Class G3 harsh environments per ISA-S71.04-1985, ensuring resistance against corrosive airborne contaminants. It is primarily utilized in large-scale process automation projects where I/O density requires multiple carriers and multi-enclosure configurations. The cable's robust design ensures signal integrity and power stability across the 6.5-meter maximum allowable LocalBus extension limit.

Technical Configuration

Ordering Information

Industrial procurement and replacement should reference both the model number and the alternate part number to ensure exact hardware matching within the DeltaV ecosystem.

Engineering & Installation Guide

Mandatory Power Sequencing:

The KJ4002X1-BF2 is not designed for "hot-swapping." This unit cannot be removed or inserted while the system power is energized. System power must be fully de-energized before disconnecting carriers or LocalBus extender cables to prevent hardware damage or unpredictable controller behavior.

LocalBus Length Constraints:

Total bus integrity is strictly dependent on cable length. The cumulative length of all I/O carriers and LocalBus Extenders in a single segment must not exceed 6.5 meters. Exceeding this limit will result in excessive voltage drop on the 12.6 VDC rail and potential signal timing errors.

Conduit and Routing Requirements:

When the KJ4002X1-BF2 is used to interconnect carriers across different enclosures, the cable must be installed within a dedicated conduit to ensure physical protection and EMC shielding. Proper separation between LocalBus cables and high-voltage AC power lines is required to prevent electromagnetic interference.

Hazardous Area Compliance:

For installations in Zone 2 hazardous areas, technicians must strictly adhere to document 12P2046 "DeltaV™ Scalable Process System Zone 2 Installation Instructions." Ensure the area is known to be non-hazardous before any physical disconnection.

Maintenance & Troubleshooting FAQ

Q: Is calibration required for the KJ4002X1-BF2?

A: No. The cable is a passive electromechanical assembly and requires no calibration or software adjustment.

Q: How do I handle a suspected cable failure?

A: This unit contains no user-serviceable parts. If the 12.6 VDC LocalBus power is absent at the downstream carrier or if I/O modules are failing to initialize, check the 44-pin seating and locking mechanisms. If the cable is physically damaged, it must be replaced as an entire assembly.

Q: Are KJ4002X1-BF2 and 12P3866X012 fully interchangeable?

A: Yes. 12P3866X012 is the internal Emerson manufacturing/engineering part number associated with the KJ4002X1-BF2 model designation. They refer to the same physical cable assembly.