NOR CONTROL NN-791 HER100261 I/O Processor Card

OverviewNOR CONTROL NN-791 HER100261 is an I/O processor card for the classic Norcontrol D2 marine automation system, now part of Kongsberg maritime control product portfolio. It serves as a local input/output processing unit responsible for collecting field sensor signals, executing local control logic, and communicating with the system main controller. This card handles analogue and digital signal acquisition and output for engine room monitoring, alarm systems and auxiliary machinery control onboard vessels. It is a legacy marine control board and has been officially discontinued, circulated globally as spare parts for retrofitting and maintenance of existing D2 systems.

FeaturesNOR CONTROL NN-791 HER100261 adopts dedicated marine-grade processing hardware with built-in signal conditioning circuit. The I/O Processor Card supports mixed analogue and digital I/O processing, on-board signal filtering and fault diagnosis; it communicates with the D2 system backplane via proprietary bus protocol. It is designed to withstand vibration, temperature fluctuation and high humidity in engine room environment, with status LED indicators for power, run and fault. It supports alarm signal latching and substitute value output during communication failure. Different variants such as NN-791.10 / NN-791.12 with suffix HER100261H / HER100261I are compatible within the same D2 rack architecture. NOR CONTROL NN-791 HER100261 cooperates with other D2 rack cards to build complete engine monitoring and alarm systems.

SpecsNOR CONTROL NN-791 HER100261 I/O processor card. The I/O Processor Card part number: NN-791 HER100261. Series: Norcontrol D2 Marine Automation. Type: Local I/O processing card. Function: Signal acquisition, local logic, rack bus communication. Mounting: D2 standard rack slot installation. Weight: approx 0.46 kg. Lifecycle: discontinued, aftermarket spare stock only. It is stocked as marine D2 alarm & monitoring system spare.

Operating ParametersNOR CONTROL NN-791 HER100261 ambient operating temperature: -20℃ ~ +60℃. The I/O Processor Card relative humidity: 5%~95% non-condensing. Protection class: IP20, cabinet rack installation. EMC: comply with marine IEC 60945 maritime equipment standards.

PrincipleNOR CONTROL NN-791 HER100261 scans field analogue and digital input signals cyclically. The I/O Processor Card converts raw signals into digital data, runs pre-configured local alarm and control logic, then exchanges data with the D2 master controller through rack backplane bus. It also receives output commands from master and drives field actuators. Processor failure, backplane communication fault or signal channel burnout will cause NOR CONTROL NN-791 HER100261 to lose signal acquisition and alarm output function.

ApplicationsNOR CONTROL NN-791 HER100261 is widely deployed in cargo ship engine control rooms, offshore platform machinery alarm consoles and legacy vessel automation panels. The I/O Processor Card undertakes engine parameters monitoring, machinery alarm, valve and pump auxiliary control, cooperating with D2 CPU, communication cards and alarm panels. NOR CONTROL NN-791 HER100261 is a preferred spare for old Norcontrol D2 marine automation system maintenance and replacement.