Kongsberg Norcontrol dPSC / RAi-16 / RDi-32 Marine Automation Modules for K-Chief & DataChief Systems

Manufacturer: Kongsberg Maritime / Norcontrol Automation
Country of Origin: Norway
Product Type: Distributed Marine Automation I/O Modules and Process Segment Communication Modules
Marine Application: Ship alarm, monitoring, machinery automation, sensor input collection, digital signal monitoring, and distributed engine-room / vessel control systems

---

Product Introduction

The equipment shown in your images consists of Kongsberg Norcontrol marine automation modules, including dPSC communication / segment controller modules, RAi-16 remote analogue input modules, and RDi-32 remote digital input modules used in K-Chief, DataChief C20, and related Kongsberg distributed marine automation systems.

These modules are not ordinary PLC cards. They are part of a distributed process and alarm monitoring architecture designed for ships, where sensor signals and equipment status inputs are collected close to the machinery and then transmitted over the vessel’s automation network to operator stations, alarm panels, and control systems.

In practical shipboard use, these modules are installed in engine control rooms, machinery cabinets, alarm monitoring panels, engine-mounted cabinets, purifier systems, auxiliary machinery control panels, and integrated automation systems. Their job is to receive analogue values such as pressure, temperature, level, flow, 4–20 mA transmitter signals, PT100 / resistance inputs, as well as digital ON/OFF signals such as pump running status, low-pressure switches, high-temperature trips, valve limit switches, tank alarms, and machinery interlocks.

For shipowners, technical superintendents, and marine engineers, these Kongsberg modules are critical because if one module fails, a large number of alarm points, analogue measurements, or machinery statuses may disappear from the ship’s monitoring system. That is why RAi-16, RDi-32, and dPSC modules remain highly demanded marine spare parts even on older vessels still operating with K-Chief or Norcontrol-based automation.

---

What Is This Equipment?

The modules in the photos belong to a distributed marine automation system. Instead of bringing every sensor wire directly to one central cabinet, Kongsberg’s architecture uses remote I/O modules placed near the machinery or grouped in distributed cabinets. These modules collect field signals and pass them into the ship’s automation network.

The main module families visible in your images are:

1) dPSC – Dual Process Segment Controller / Communication Module

The dPSC acts as a communication and segment interface module within the distributed automation system. In K-Chief documentation, the dPSC is described as a gateway / process segment controller used for communication and segmentation between distributed process units and the higher-level automation system. It provides logical and galvanic isolation between segments and supports the network architecture of the automation system.

2) RAi-16 – Remote Analogue Input Module

The RAi-16 is a 16-channel analogue input module. It is used to collect analogue signals from field devices such as:

• pressure transmitters
• temperature transmitters
• tank level transmitters
• flow sensors
• resistance / PT100 / RTD-type sensor circuits depending on module configuration
• standard current or voltage signals from marine instrumentation

Kongsberg documentation describes RAi-16 / RAi-16xe as a flexible analogue input module for the most common signal types in a marine automation system.

3) RDi-32 – Remote Digital Input Module

The RDi-32 is a 32-channel digital input module used for ON/OFF and status signals. These typically include:

• pump running / stopped feedback
• motor trip signals
• valve open / closed limit switches
• low level / high level alarms
• pressure switch contacts
• fire door / watertight door status
• purifier and separator status signals
• machinery fault contacts

In short, these modules are the signal collection backbone of the ship’s alarm and monitoring system.

---

Main Features

1) Distributed Marine I/O Architecture

These modules are designed for distributed installation. Instead of routing every sensor cable to one large central PLC, the ship can install input modules close to the machinery area. This reduces cable length, simplifies expansion, and improves signal organization.

2) High Channel Density

• RAi-16 provides up to 16 analogue input channels
• RDi-32 provides up to 32 digital input channels

This allows a large number of engine-room signals to be collected in a compact cabinet arrangement.

3) Designed for Marine Alarm & Monitoring Systems

These modules are intended for shipboard use in systems such as:

• machinery alarm monitoring systems
• engine room automation
• tank monitoring and level systems
• power management / auxiliary monitoring
• integrated vessel automation platforms

4) Support for Common Marine Sensor Signals

RAi-16 modules are used for common marine sensor types such as current, voltage, and resistance-based measurements. Kongsberg’s remote analogue input module documentation highlights flexibility for typical marine analogue signal processing.

5) Digital Status Monitoring for Machinery Protection

RDi-32 modules allow the system to monitor a large number of discrete contacts from engines, pumps, valves, switches, and alarm devices.

6) CAN-Based Distributed Communication

Kongsberg distributed process units use network communication between the modules and the control system. Documentation for RAi-16xe refers to redundant CAN Open high-speed fieldbus communication, which reflects the distributed design philosophy of the system family.

7) Segment Isolation and Communication via dPSC

The dPSC module is a very important part of the architecture because it handles process segment communication, helping connect and isolate the remote I/O network structure. K-Chief documentation references dPSC as a process segment controller within the distributed system.

8) Direct Use in Harsh Marine Environments

These modules are intended for shipboard conditions and are used in engine rooms, auxiliary machinery spaces, and control cabinets where vibration, temperature changes, and electrical noise are common realities of marine operation.

---

Main Components

Although each module type has a different function, the visible construction in your images shows the typical Kongsberg Norcontrol module architecture.

1) Front Terminal Interface

Each module has front terminal blocks for connection of field wiring. These terminals are used for:

• sensor inputs
• digital contact inputs
• power supply
• communication bus wiring
• common / return / shield connections

2) Signal Conditioning and Input Electronics

Inside the RAi-16 analogue module, the electronics process raw analogue signals from field instruments. This includes:

• input scaling and conditioning
• sensor supply / reference circuits where applicable
• filtering and analogue-to-digital conversion
• fault detection / channel status logic

3) Digital Input Processing Section

In the RDi-32 module, the input electronics monitor the state of discrete signals from external equipment and convert them into automation system status data.

4) Status / Diagnostic LED Section

The module front panels include LED indications for:

• power status
• module run / watchdog / status
• communication / serial I/O / CAN activity
• segment or channel diagnostic condition depending on module type

5) Communication Interface Section

The modules are designed to communicate with the Kongsberg automation network. This communication section links the field I/O to the central alarm and monitoring system.

6) dPSC Segment Controller Logic

The dPSC module serves as a communication and segmentation interface between distributed modules and the automation network. In practical terms, it helps keep the remote I/O system organized and connected to the main system.

7) Module Housing and Mounting Frame

The metal housing and front-access layout are suitable for mounting in marine automation cabinets and for maintenance access during shipboard service.

8) Internal Configuration / Boot / Service Areas

From the markings visible on these modules, some units include boot, serial I/O, status, CAN, and configuration-related sections used during commissioning, diagnostics, or system maintenance.

For spare-parts planning, the most commonly requested items are:

• complete RAi-16 analogue input modules
• complete RDi-32 digital input modules
• dPSC communication / segment controller modules
• matching terminal strips / plugs
• revision-matched replacement units
• related Kongsberg alarm monitoring modules such as RDo, RAo, or other DPU family parts

---

Applications on Ships

These Kongsberg Norcontrol modules are widely used in marine alarm and monitoring systems for gathering signals from machinery and ship systems. Common applications include:

Main Engine Monitoring

• jacket water temperature
• lube oil pressure
• piston cooling / bearing temperatures
• engine shutdown and slow-down signals
• engine auxiliary status inputs

Auxiliary Engine / Generator Monitoring

• generator alarms
• engine running feedback
• fuel oil pressure and temperature
• cooling water and lube oil conditions
• overspeed / trip / common alarm signals

Boiler and Burner Systems

• burner status contacts
• flame failure alarms
• low fuel pressure switches
• feed water alarms
• boiler safety chain monitoring

Purifier / Separator / Fuel Treatment Systems

• separator running status
• heater temperature signals
• sludge tank alarms
• pressure and flow feedback
• interlock signals

Pump, Compressor, and Cooling Systems

• running / stopped / trip signals
• suction and discharge pressure transmitters
• bearing and winding temperature inputs
• low-flow / no-flow switches

Tank Monitoring and Utility Systems

• tank level alarms
• bilge alarms
• service tank level transmitters
• ballast / fresh water / sludge monitoring inputs

General Ship Alarm & Monitoring

• fire and safety contacts
• watertight door status
• remote shutdown indications
• cargo machinery status on specialized vessels
• central AMS / IAS input expansion

These modules are especially important in ships fitted with K-Chief / DataChief alarm and automation systems, where distributed I/O is used throughout the vessel.

---

Common Problems & Troubleshooting

Because these are distributed I/O modules, failures may appear in the control room as missing measurements, false alarms, dead alarm points, frozen values, or communication faults. Below are the most common problems encountered onboard.

1) RAi-16 Module Not Reading Analogue Signals

Symptoms

• pressure / temperature / level value missing
• value frozen at zero or maximum
• bad sensor alarm or out-of-range reading
• several analogue channels dead on the same module

Possible causes

• loss of 24 VDC module power
• failed input channel electronics
• incorrect field wiring after maintenance
• broken transmitter loop or sensor cable
• sensor supply problem
• module internal fault
• wrong scaling or wrong sensor type assignment in the automation system

Checks

• verify module power LED and status indication
• measure loop current / sensor signal at terminal level
• compare field signal with module reading
• inspect channel wiring and common return
• verify whether the transmitter itself is healthy
• check if multiple channels are affected or only one channel

---

2) RDi-32 Digital Inputs Not Changing Status

Symptoms

• pump shown stopped although running
• alarm contact status not updating
• multiple input points dead on one module
• intermittent ON/OFF status in AMS

Possible causes

• blown input common / field supply issue
• loose terminal wiring
• failed digital input section
• faulty external limit switch or pressure switch
• damaged contact signal cable
• moisture / corrosion on terminals

Checks

• measure input voltage / contact state at the module terminal
• test the field contact locally
• compare actual field status with the system indication
• inspect if one group of channels or all channels are affected
• check for broken common return wiring

---

3) dPSC Communication Fault / Segment Failure

Symptoms

• several remote modules disappear from the system
• multiple analogue and digital points fail together
• communication alarm between segment and control system
• watchdog / run / communication LEDs abnormal

Possible causes

• dPSC failure
• CAN / segment communication cable problem
• power supply failure to remote segment
• wrong module addressing / network issue after replacement
• loose connector or damaged bus termination

Checks

• inspect dPSC status LEDs
• verify segment power supply
• check communication cabling and terminations
• identify whether all modules on one segment are affected
• confirm whether the fault appeared after module replacement or electrical work

---

4) Random False Alarms from Multiple Channels

Possible causes

• unstable 24 VDC supply
• poor grounding / shielding
• noise on analogue loops
• common return fault
• water ingress in cabinet
• ageing module electronics

Checks

• inspect power quality and cabinet grounding
• verify shield termination practices
• check for moisture or corrosion
• review whether false alarms appear during heavy machinery starting or switching events

---

5) Module Shows Power but No Valid Data

Possible causes

• internal processor / communication fault
• watchdog failure
• corrupted configuration / addressing issue
• broken communication link to the system
• partially failed module

Checks

• compare module LED status with healthy neighbouring modules
• reseat plugs and inspect connectors during shutdown
• swap with known-good spare only if approved by ship procedures and configuration compatibility is confirmed
• confirm revision compatibility before replacement

---

6) One Channel Fault but Module Otherwise Healthy

Possible causes

• failed sensor
• wrong transmitter range
• broken field wire
• one damaged input channel
• incorrect termination after repair

Practical note

When only one channel is bad, do not immediately condemn the full module. First prove:

• the sensor is healthy
• the cable is healthy
• the correct signal type is present at the module input

---

Typical Failure Modes Seen in Service

For older Kongsberg Norcontrol modules, common workshop findings may include:

• failed input conditioning circuits
• communication interface faults
• damaged DC power section
• oxidized connectors
• cracked solder joints due to vibration
• damaged opto-isolation / digital input stages
• burnt protection components from electrical surges
• terminal block damage from overheating or loose wiring

Because many of these modules remain in service for years, repair, refurbishment, and exchange supply are still practical solutions where new stock is unavailable or lead time is too long.

---

Maintenance Tips

1) Keep Cabinet Environment Clean and Dry

Marine automation cabinets should be protected from:

• oil mist
• salt-laden humidity
• water ingress
• loose cable shields touching terminals
• conductive dust and corrosion

2) Inspect Terminal Tightness Periodically

Loose terminals can create:

• unstable analogue values
• false digital alarms
• heat damage at terminals
• intermittent communication or common-return faults

3) Verify 24 VDC Power Quality

Many mysterious module faults are actually caused by unstable or low control power. Check:

• module supply voltage
• ripple or instability from power supplies
• fuse condition
• common return integrity

4) Label and Document Field Wiring Before Replacing Modules

These modules have many channels. Before removing one:

• photograph all wiring
• mark terminal positions clearly
• confirm channel mapping from the automation drawings
• verify revision and part number

5) Keep a Tested Spare Module Where Possible

For vessels with older K-Chief / DataChief systems, it is wise to keep critical spares such as:

• one RAi-16
• one RDi-32
• one dPSC
  if the system is still heavily dependent on these modules.

6) Check Cabinet Ventilation and Temperature

Overheated cabinets shorten the life of electronics and power-conditioning components.

7) During Drydock or Planned Maintenance, Review Channel Health

Compare field instrument calibration and actual module readings to identify drifting or suspicious channels before they become operational problems.

SM MARINE SERVICE™ can support shipowners and managers with replacement, repair, spare sourcing, and identification support for these Kongsberg Norcontrol modules when clear photos, part numbers, and system details are available.

---

Why Ships Still Use This Equipment

Many ships continue to operate with Kongsberg K-Chief and Norcontrol-based alarm monitoring systems because the systems are robust, proven, and deeply integrated into vessel operations. Even when the ship is not being fully upgraded, the distributed I/O modules remain essential because they handle the real field signals from the machinery.

Ships still use these modules because they offer:

Proven marine reliability

These modules were designed specifically for marine automation and are widely used across commercial vessels.

Distributed installation flexibility

Remote I/O reduces cable runs and simplifies large automation systems.

Strong compatibility with existing ship automation

Replacing an entire automation platform is expensive. It is often far more practical to keep the existing Kongsberg architecture running by replacing or repairing failed modules.

High spare-parts demand but continued support potential

Although some revisions are older, many vessels still need:

• RAi-16
• RDi-32
• RDo-16
• RAo-8
• dPSC
• related K-Chief / DataChief modules

This creates continuing demand for tested used, refurbished, and reconditioned modules.

---

Frequently Asked Questions (FAQ)

1) What is the function of the Kongsberg RAi-16 module?

The RAi-16 is a remote analogue input module used to collect analogue signals such as pressure, temperature, level, flow, current, voltage, and resistance-based sensor signals in a marine automation system.

2) What does the RDi-32 module do?

The RDi-32 is a 32-channel remote digital input module used for ON/OFF, trip, running, alarm, and switch-status signals from ship machinery and auxiliary systems.

3) What is the dPSC module used for?

The dPSC is a process segment / communication controller module used within the distributed Kongsberg automation network for segment communication and system architecture support.

4) Are these modules used in K-Chief systems?

Yes. These module families are associated with Kongsberg K-Chief / Norcontrol / DataChief marine automation systems and related distributed process unit architectures.

5) What part numbers are commonly associated with these modules?

Examples commonly seen in the market include:

• RAi-16 – 8100148
• RDi-32 – 8100154
• RDo-16 – 8100155
• dPSC – 8100183
  These references appear across marine spare-parts listings and Kongsberg-related market sources.

6) Can these modules be repaired?

Yes, in many cases they can be repaired or refurbished depending on the fault. Common repairable problems include power-section damage, communication faults, input-stage damage, and connector issues.

7) What information should be sent before ordering a spare?

Please provide:

• clear front and side photos
• exact module name
• part number
• revision number
• vessel / automation system name if known
• fault description
• quantity required

8) Can a wrong revision cause problems?

Yes. In older marine automation systems, revision compatibility can matter. It is always safer to match the module type, part number, and revision as closely as possible unless a confirmed substitute is approved.

---

Short Product Description

Kongsberg Norcontrol dPSC, RAi-16, and RDi-32 modules are distributed marine automation I/O modules used in K-Chief, DataChief, and related Kongsberg ship alarm and monitoring systems. The RAi-16 module is used for analogue sensor inputs, the RDi-32 module is used for digital status and alarm inputs, and the dPSC module is used for process segment communication and distributed network architecture. These modules are widely installed in ship engine-room alarm systems, auxiliary machinery monitoring, tank monitoring, and integrated vessel automation systems. They remain important spare parts for maintaining older Kongsberg Norcontrol marine automation platforms.

---

-

+

Buy Now