8922-RB-IS Wiring Protection Module – MTL

Description

8922-RB-IS Wiring Protection Module – MTL

8922-RB-IS Wiring Protection Module – MTL

Fault Tolerant Redundant LAN

The availability of Ethernet connections – between SafetyNet and standard Controllers, historian and asset management packages and HMI stations – has a significant impact on the effectiveness and availability of both safety and control functions. To maximise availability of the Ethernet LAN, MOST SafetyNet Systems feature Fault Tolerant Ethernet ports that monitor the integrity of their local network and automatically switch to an alternate path if the existing path becomes unavailable. If suitable Ethernet switches are used – such as Moxa Industrial Ethernet Switches – they too will monitor their local network and switch to an alternative path when this is required. Monitoring the local network paths – even when they are not being used – allows the system to report the loss of any failed paths so that appropriate maintenance can be carried out.

Moxa Industrial Ethernet Switches

The Moxa Ethernet Switch range is specifically designed for use in Industrial applications that require high availability in harsh environments, with a broad operating temperature range (-40ºC to +75ºC, except EDS-205: -10ºC to +60ºC) and hazardous area mounting capability (Class 1, Div 2 or Zone 2). Two alternative topologies are shown in figures 1 and 2. Which topology is preferred will depend on the physical layout of the entities on the LAN and local preferences. Figure 1 shows a redundant Ethernet LAN, with intra-LAN link whilst figure 2 shows a single “Turbo Ring” that provides an alternate means of ensuring Ethernet availability – implemented in the Moxa EDS405 5-port switch. If any part of the Turbo Ring fails, communication is re-routed automatically within 300ms. Further improvements to availability can be achieved by putting in place a second identical, “Turbo Ring” which should be connected to the first ring by a single intra-LAN link. This link would normally be mounted in the control room. The Moxa switches are available with either all copper or a combination of copper and fibre ports. For media conversion between fibre and copper the MOXA IMC-101 can be used. All the Moxa products (except the EDS-205) have dual power supply inputs and a relay output for user configurable fault reporting.

The sequence control and interlocking protection boiler protection logic consists of several parts, including MFT boiler trip protection logic, sequence control and interlocking.

1) The tripping protection condition of the main fuel in the boiler tripping protection logic is a comprehensive boiler protection measure based on various control conditions during normal combustion operation of the boiler. Its purpose is to ensure that the bed temperature of the boiler is sufficiently high, so that the fuel entering the furnace can be continuously and stably burned. Usually, when the following situations occur, the boiler should be shut down urgently and a mandatory main fuel trip action should be implemented. The conditions for triggering boiler protection are as follows: when the forced draft fan trips, all induced draft fans trip, any three of the furnace bed temperature measurement points exceed 1050 ℃, the furnace pressure is ultra-low, the steam drum water level is ultra-high (the water level value is higher than+200mm and delayed for 5 seconds), and the steam drum water level is ultra-low (the water level value is lower than -200mm and delayed for 5 seconds), press the MFT manual button. After the main fuel protection action, the command is issued to automatically stop sending coal, coal slurry, and air supply fans to the furnace interior. At the same time, it is decided whether to stop the induced draft fan and close the desuperheating water valve based on the on-site situation. When the induced draft fan is not stopped, the induced draft volume entering the furnace should be carefully controlled, and should not be blindly reduced immediately.

2) The basic purpose of sequential control and interlocking of boiler auxiliary equipment is to minimize the adverse effects on the equipment caused by the working conditions of the boiler and auxiliary equipment during normal operation, in order to ensure the long-term use of the equipment. Its main function is to limit the instantaneous action mode of the device by relying on pre-set protection actions when the device does not meet operating conditions or approaches an unstable and unsafe operating state during normal operation, ultimately ensuring the safety of the equipment. The DCS control system of this circulating fluidized bed boiler has designed multiple sets of sequential and interlocking control circuits, including induced draft fan, forced draft fan, coal feeder, electric valves of the water system, and electric and safety valves of the steam system. The setting of these interlocking logic provides basic guarantees for the safe and stable operation of the boiler, and also provides relatively standardized equipment operation procedures for the operators of the power plant.

Kollmorgen products:
AKM31E-ACCND-01
AKM31E-ACCNR-00
AKM31E-ACCNR-01
AKM31E-ACDNC-00
AKM31E-ACDNC-01
AKM31E-ACMN1-00
AKM31E-ACMNC-00
AKM31E-ACMNC-01
AKM31E-ANC2C-00
AKM31E-ANC2R-00
AKM31E-ANCN1-01
AKM31E-ANCNC-00
AKM31E-ANCNC-01
AKM31E-ANCNR-00
AKM31E-ANCNR-01
AKM31E-ANCNS-02
AKM31E-ANDNC-00
AKM31E-ANDNC-01
AKM31E-ANMNC-00
AKM31E-ANMNC-01
AKM31E-ANMNR-00
AKM31E-ANMNR-02
AKM31E-ANPNC-00
AKM31E-ANPNC-01
AKM31E-CNCNC-01
AKM31E-CNMNC-00
AKM31E-GCCNR-00
AKM31H-ACC22-00
AKM31H-ACCN2-00
AKM31H-ACCNC-00
AKM31H-ACDNC-00
AKM31H-ACM22-00
AKM31H-ACMN2-00
AKM31H-ACPNC-00
AKM31H-ANC22-00
AKM31H-ANC22-01
AKM31H-ANCN2-00
AKM31H-ANCN2-01
AKM31H-ANCNC-00
AKM31H-ANCNR-00
AKM31H-ANMN1-00