Description
Product Overview
The ABB NTDI01 Digital I/O Termination Unit is a field-wiring interface used in Bailey INFI 90 and Network 90 process control systems. It provides the physical connection points between field devices and compatible control-system I/O modules, helping route discrete signals into or out of the control system. Unlike a processor or standalone I/O slave module, the NTDI01 primarily provides termination and signal-configuration functions. Its operation depends on the connected module, cable arrangement, field wiring, and configured signal type.
The NTDI01 supports several hardware arrangements across the Bailey I/O family. Documented applications include the IMDSI02 digital slave input module, IMDSM05 digital I/O slave module, IMDSO01/02/03 and IMDSO04 digital output modules, and other compatible modules. The exact wiring and dipshunt settings differ by application. For example, the IMDSI02 can accept 24 VDC, 125 VDC, or 120 VAC inputs in its documented configuration. Those ratings should not be generalized to every module connected through an NTDI01; the applicable module manual and wiring diagram determine the permitted signal type.
For maintenance and procurement, the main risk is assuming that the termination unit can be replaced without checking its configuration. Dipshunts establish the required signal path, and certain terminal connections may be internally linked depending on the selected application. Before removing an installed unit, document the existing dipshunt positions, terminal wiring, field supply arrangement, and cable connection. When buying a replacement ABB NTDI01, check the board markings and condition, verify compatibility with the installed I/O module, and request inspection evidence. A physically matching board is not sufficient proof that the original signal configuration will be preserved.
Product Introduction
The NTDI01 is intended for installations that use Bailey INFI 90 termination hardware to connect field signals to control-system modules. It can be part of digital input, digital output, or other documented I/O arrangements, depending on the connected module and wiring scheme. It mounts to a compatible field termination panel and works with the appropriate termination cable and module hardware.
During replacement, isolate the relevant equipment according to site procedures and follow the applicable Bailey instruction manual. Record the wiring and dipshunt positions before disconnecting the original unit. For used or refurbished stock, request photographs of the board, terminal blocks, connectors, and identification markings, along with a clear statement of condition and testing performed. Functional verification should cover the intended signal configuration rather than relying solely on a visual inspection.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | |
| Manufacturer | ABB Bailey Controls |
| Product Type | Digital I/O termination unit |
| System Family | Bailey INFI 90 / Network 90 |
| Primary Function | Field-signal termination and I/O signal configuration |
| Compatible I/O Hardware | Includes documented IMDSI02, IMDSM05, IMDSO01/02/03, IMDSO04, IMASO01, and IMDSM04 applications; verify the specific arrangement |
| Input Signal Types | Application-dependent; documented IMDSI02 configuration supports 24 VDC, 125 VDC, and 120 VAC inputs |
| Output Configuration | Depends on the connected output module and selected wiring arrangement |
| Configuration Method | Dipshunts |
| Cable | NKTU01 is documented for applicable -to-module connections |
| Mounting | Compatible INFI 90 field termination panel |
| Ambient Temperature | 0°C to 70°C |
| Relative Humidity | 0–95% up to 55°C, noncondensing; 0–45% at 70°C, noncondensing |
| Altitude | Sea level to 3 km |
| Protection Rating | Not verified as an IP-rated enclosure specification |
| Communication Protocol | Not applicable as a standalone communication module |
Specifications are drawn from Bailey documentation. Signal ratings and terminal assignments must be checked against the manual for the specific I/O module and application.
NTDI01
Related Products
These components are associated with the family or documented applications; they are not all interchangeable.
- IMDSI02 — Digital slave input module.
- IMDSM05 — Digital I/O slave module.
- IMDSO01 / IMDSO02 / IMDSO03 — Digital slave output modules.
- IMDSO04 — Digital slave output module.
- IMDSM04 — Pulse input slave module.
- IMASO01 — Analog slave output module.
- NKTU01 — Termination-unit cable used in documented arrangements.
- NFTP01 — Field termination panel.
Frequently Asked Questions
Q1: What is the ABB used for?
It provides field-wiring termination and configurable signal connections for compatible Bailey INFI 90 I/O modules. It is not a standalone processor or general-purpose I/O controller.
Q2: Is the a digital input module?
Not exactly. It is a termination unit. The actual input or output function is determined by the connected I/O module and the selected wiring configuration.
Q3: Which modules can use the ?
Bailey documentation lists multiple compatible applications, including IMDSI02, IMDSM05, IMDSO01/02/03, IMDSO04, IMASO01, and IMDSM04. Verify the exact module and wiring arrangement before replacement.
Q4: Does the support 120 VAC and 125 VDC signals?
These signal types are documented for specific configurations, including the digital input application. Do not assume every installation supports these voltages; check the connected module’s manual and wiring diagram.
Q5: What are the dipshunts used for?
Dipshunts configure signal paths and wiring arrangements for the selected application. Incorrect settings can prevent proper operation or create an unsafe electrical arrangement. Record the original settings and follow the relevant installation instructions.
Q6: What should I check before ordering a replacement?
Verify the model marking, connected I/O module, terminal-block condition, dipshunt positions, termination cable, and mounting arrangement. Request clear photographs and confirm whether the unit is new, surplus, refurbished, or repaired.
Q7: What environmental limits are documented?
The manual lists an ambient operating range of 0°C to 70°C, with relative-humidity limits that vary by temperature. Confirm that the cabinet environment stays within the documented limits.
Procurement Recommendation
For the ABB , verify the connected Bailey I/O module and existing dipshunt configuration before selecting a replacement. Pay particular attention to field voltage, internally connected terminals, and the termination cable. For refurbished equipment, request condition details and evidence that the terminal blocks and board are suitable for the intended application. The correct termination unit is only one part of a working I/O path; wiring and configuration must also match the original system.
