Woodward MicroNet ™ Analysis and Application of Simplex and Plus Digital Control Systems

Module level redundancy: Connect two external input devices to two independent I/O modules

Output redundancy can be achieved by adding external relays, and for actuator output, a dual coil actuator can be used to ensure continuous operation in the event of a single point fault.

3、 Detailed Explanation of Chassis Configuration

3.1 14 slot chassis

The MicroNet Plus 14 slot chassis provides redundant CPU capability and more I/O slots, while improving airflow and system reliability. The chassis adopts a modular design, with each module containing a pre formed cage, cooling fan, and high-temperature detection temperature switch. The chassis has a total of 14 CPU and I/O slots available for use.

The main features include:

New dual slot wide redundant load sharing power supply

Redundant intelligent fans can provide early notification of fan failures

The motherboard has a built-in temperature switch with a trigger point of 65 ° C ± 3 ° C

Support redundant hot swappable CPUs

3.2 8-slot chassis

The MicroNet Plus 8-slot chassis also provides redundant CPU capability and more I/O slots, adopting similar design concepts and technical features as the 14 slot chassis. The chassis has a total of 8 CPU and I/O slots available for use, and also features redundant intelligent fans and temperature monitoring functions.

4、 Analysis of CPU module technology

4.1 CPU P1020 module

The CPU P1020 module is based on an 800 MHz dual core processor, equipped with 512 MB RAM and 768 MB flash memory, and supports multiple communication peripherals, including 4 Ethernet ports (2 1000 Mbps, 2 100 Mbps), 2 real-time network ports, 1 service port, and 5 CAN ports.

This module supports both simplex and redundant operation modes, designed specifically for working environments in the industrial market from 0 ° C to+55 ° C. The module supports hot swapping, but it should be reset before removal to ensure elegant system failover.

4.2 PowerPC CPU 5200 module

The PowerPC CP5200 module uses the Motorola MPC5200 processor, equipped with 128 MB DDR RAM and 64 MB flash memory, and supports multiple communication peripherals, including 2 Ethernet ports, 2 real-time network ports, 1 serial port, 1 service port, and 2 CAN ports.

This module is designed for extreme industrial environments ranging from -40 to+85 ° C, with built-in FPGA providing VME bus master/slave functionality and other functions required for redundant systems.

5、 Communication module and network topology

5.1 Remote RTN module

The Remote Real Time Network (RTN) module is designed for rack expansion, with the main function of collecting local I/O module data and communicating with the host rack CPU, while providing redundant fault switching control for the rack. The RTN module supports simplex and redundant systems, and each RTN expansion chassis installs a remote RTN module in the first slot (CPU1).

5.2 SIO module

The SIO (Serial Input/Output) intelligent enhancement module provides four serial communication ports and interfaces with the VME bus. Module manages four serial ports: Port 1 and Port 2 are RS-232 ports; Ports 3 and 4 support RS-232, RS-422, or RS-485 communication protocols. The module has two LEDs (running and faulty) and no switch.

6、 Discrete I/O module

6.1 48/24 Discrete Combination Module

The HDDIO module provides 48 optically isolated discrete inputs and 24 discrete outputs, without calibration, and can be directly replaced with modules of the same model. This module supports two types of FTM I/O configurations:

Configuration 1: A 48/24 discrete FTM is connected to the HDDIO module via two high-density analog/discrete cables, and then connected to a 32 channel relay module or two 16 channel relay modules via low-density discrete cables.

Configuration 2: Two 24/12 discrete FTMs (DIN rail mounted) are connected to the HDDIO module via two high-density analog/discrete cables.

6.2 48 channel discrete input module

Each 48 channel discrete input module is connected to two independent FTMs through two low-density discrete cables. The module provides discrete signal inputs for 48 independent switch or relay contact points, which are optically isolated from other parts of the MicroNet control circuit.

6.3 64 channel discrete output module

The 64 channel discrete output module can independently control 64 outputs and operate according to commands from the CPU module. The module has no potentiometer and does not require calibration. It can be directly replaced with modules of the same model. This module can be connected to two 32 channel relay modules, four 16 channel relay modules, or a combination of both types.

7、 Analog I/O module

7.1 Intelligent Enhancement Module for Speed Sensor

This module provides four speed inputs, factory configured as MPU or Eddy inputs. The module has no potentiometer and does not require calibration. It can be directly replaced with modules of the same model. The speed input configuration depends on the module material number.

7.2 24/8 Simulated Intelligent Enhancement Module

This module provides 24 analog inputs and 8 4-20 mA outputs, without potentiometers or calibration, and can be directly replaced with modules of the same model. The module offers three different configurations, and all 4-20 mA analog inputs can be used with two-wire ungrounded (loop powered) transmitters or isolated (self powered) transmitters.