Product Overview

The Foxboro RH916DC is an I/A Series termination cable used to connect termination hardware with associated I/A Series I/O equipment in a process-control cabinet. It forms part of the fixed interconnection between the field wiring termination section and the electronic I/O section of the control system.

In an I/A Series installation, field instruments are normally brought into an organized termination arrangement before their signals reach the I/O hardware. The RH916DC carries the corresponding electrical connections between these two sections, allowing the termination and I/O functions to remain physically organized within the cabinet.

The RH916DC is a passive cable assembly rather than an active I/O or processing device. Its purpose is to preserve the intended signal path between compatible termination hardware and I/A Series I/O equipment. This makes it relevant to cabinet construction, system replacement, maintenance, and refurbishment work on established Foxboro installations.

Technical Specifications

Product Features

• I/A Series termination cable for Foxboro process-control installations
• Connects compatible termination hardware with associated I/A Series I/O equipment
• Supports organized field-signal routing inside control-system cabinets
• Functions as a passive electrical interconnection
• Maintains the separation between field termination and electronic I/O hardware
• Suitable for replacement of existing termination cables during system maintenance
• Supports cabinet refurbishment while retaining the established I/A Series architecture
• Useful where the termination and I/O sections require a longer interconnection path
• Supports structured point-to-point signal routing within the I/A Series I/O arrangement
• Suitable for established process-control and industrial automation installations

Working Principle

The RH916DC carries the electrical connections between the I/A Series termination arrangement and the associated I/O hardware. For an input signal, the process instrument sends its signal through field wiring to the termination assembly. The corresponding connection then passes through the RH916DC toward the I/A Series I/O interface.

Field Device → Field Wiring → Termination Assembly → RH916DC → I/A Series I/O Hardware → Control System

For an output circuit, the signal path operates in reverse. A command generated by the control system passes through the I/A Series I/O hardware, RH916DC, and termination arrangement before reaching the connected field device.

The cable does not independently interpret, condition, or control the signal. Those functions are performed by the associated I/A Series I/O and control hardware. The RH916DC maintains the electrical path required for the cabinet-level I/O architecture.

During installation or replacement, the two ends of the cable must be matched with their intended connection points. Correct point identification is particularly important in a large I/O cabinet because an incorrectly routed termination cable can result in an apparent connection while assigning a field point to the wrong I/O channel.

Role in an I/A Series Control Architecture

The RH916DC occupies the interconnection layer between field termination and the I/A Series I/O subsystem. It allows field wiring to be organized at a termination point while maintaining the required electrical connection to the system’s I/O electronics.

Industrial Applications

Installation and Maintenance

1. Verify the part number — Confirm that RH916DC is the correct cable for the intended I/A Series termination and I/O arrangement.
2. Review cabinet documentation — Check applicable wiring diagrams, termination information, and I/O documentation before starting the replacement.
3. Isolate the affected system section — Follow the plant’s approved shutdown and electrical isolation procedure before disconnecting the existing cable.
4. Identify both cable ends — Record the termination-side and I/O-side connection points before removing the original cable.
5. Inspect the replacement cable — Check the cable assembly for visible damage, contamination, deformation, or damaged connection areas.
6. Remove the existing cable carefully — Disconnect the original cable without placing excessive mechanical stress on the termination or I/O hardware.
7. Verify the cable route — Compare the intended RH916DC routing with the original cabinet arrangement and avoid unnecessary mechanical strain.
8. Install the replacement — Connect the cable to the designated termination and I/O interfaces and ensure that each connection is fully seated.
9. Confirm point identification — Check that the cable connections correspond to the intended termination positions and I/O points.
10. Verify electrical continuity — Where required by the maintenance procedure, perform appropriate continuity checks before restoring the affected system section.
11. Perform a controlled signal test — After energization, check the affected I/O points for expected signal behavior and review any unexpected system diagnostics.
12. Document the work — Record the cable model, cabinet location, affected I/O section, and relevant inspection or replacement details for future maintenance.

Related Components

Recommended Related Models

Key Advantages

• Provides a dedicated electrical connection between I/A Series termination and I/O hardware
• Supports organized field-signal routing within process-control cabinets
• Maintains the established Foxboro I/A Series termination architecture
• Functions as a passive interconnection rather than an active processing component
• Suitable for maintenance and replacement of existing I/A Series installations
• Supports structured separation between field wiring and electronic I/O hardware

Technical FAQs

What is the RH916DC used for?

The RH916DC is used as an I/A Series termination cable between compatible termination hardware and associated I/O equipment. It forms part of the cabinet-level electrical path between field termination and the I/O system.

Is the RH916DC an active I/O component?

No. The RH916DC is a passive cable assembly. It does not execute control logic or independently process field signals; those functions are performed by the connected I/A Series hardware.

Why should the original cable routing be documented before replacement?

The termination cable forms part of the field-point connection path. Recording both connection ends and the original routing helps ensure that each field point remains associated with the intended I/O location after replacement.

What checks should be performed after installing the RH916DC?

The termination and I/O connections should first be checked for proper seating and correct point identification. Where required, continuity testing should be followed by a controlled signal check and review of I/A Series diagnostics before the affected system is returned to normal operation.