Description
The 2 Amp Relay Output module, IC694MDL940, provides 16 normally– open relay circuits for controlling output loads. The output switching capacity of each output is 2 Amps. The output points are in four groups of four points each. Each group has a common power output terminal. The relay outputs can control a wide range of load devices, such as: motor starters, solenoids, and indicators. Power for the internal relay circuits is provided by the +24 volt DC bus on the backplane.
The user must supply the AC or DC power to operate field devices. Individual numbered LEDs show the ON/OFF status of each output point. There are no fuses on this module. The red bands on the label show that MDL940 is a high-voltage module. This module can be installed in any I/O slot in an RX3i system.
Refer to Appendix A for product standards and general specifications. * When this module is used with DC power supply IC695PSD040 or PSD140, special precautions should be taken because dropouts in the source voltage will be seen by this module and may cause relay dropouts.
Maintain the DCS system, mainly including:
(1) Maintenance personnel should understand the overall design concept of the system. Familiar with the structure and functional composition of DCS system, familiar with the hardware knowledge of system equipment, familiar with the normal and abnormal states of various components such as controllers, IO cards, power supplies, etc., proficient in DCS configuration software.
(2) System backup: including operating system, driver program, boot disk, control system software, authorization disk, control configuration database, and control configuration data to be up-to-date and complete. To address the issue of discs being prone to wear and tear in practical use, it is important to make frequent backups and use backup forms such as mobile hard drives, USB drives, and hard drives to ensure the preservation of various software.
(3) Hardware reserve: For vulnerable and short life components and key components such as keyboard and mouse, I/O module, power supply, communication card, etc., appropriate backup should be made according to the actual situation, ensuring that there is no less than one spare part for each type of card and module, and stored according to the manufacturer’s requirements. If conditions permit, the spare parts should be verified to effectively grasp the status of the spare card and module.
(4) Organize the after-sales service scope and schedule of various products, form a contact list of technical support personnel from hardware manufacturers and system design units, and fully utilize the technical support of DCS suppliers and system design units.
Daily maintenance
The daily maintenance of the system is the foundation for the stable and efficient operation of the DCS system, and the main maintenance work includes the following points:
(1) According to the 25 countermeasures requirements, DL/T774 maintenance regulations and other system documents, improve the DCS system management system.
(2) Ensure good sealing of electronic equipment rooms, prevent small animals from entering, reduce the adverse effects of dust on component operation and heat dissipation, ensure that the temperature and humidity comply with the manufacturer’s regulations, and avoid condensation on system equipment due to rapid changes in temperature and humidity. Consider introducing the environmental temperature signal from the DCS electronic room into the CRT with an alarm.
(3) Check every day whether the fans in each cabinet of the system are working properly and whether the air ducts are blocked to ensure that all equipment in the system can operate reliably for a long time.
(4) Ensure the quality of the system’s power supply and provide reliable power to both power sources. When either power source is lost, an alarm will sound.
(5) It is prohibited to use wireless communication tools between electronic devices to avoid electromagnetic interference with the system, to avoid moving operating stations, displays, etc. during operation, and to avoid pulling or damaging equipment connection cables and communication cables.
(6) Standardize the management of DCS system software and application software, and software modifications, updates, and upgrades must comply with the approval authorization and responsible person system. It is strictly prohibited to use non genuine software or install software unrelated to the system, and close the management of the host’s USB port, optical drive, etc.
(7) Do a good job of recording system data such as PID parameters and positive and negative effects of regulators for each control circuit.
(8) Check if the control host, monitor, mouse, keyboard, and other hardware are intact, and if real-time monitoring is working properly. Check the fault diagnosis screen for any fault prompts.
(9) DCS equipment, including DPU and human-machine interface station, should be powered on one by one in a certain order. After each device is powered on and observed to be normal, the next device should be powered on to avoid any abnormalities that are difficult to analyze. After powering on, the communication connector should not collide with the conductive body such as the cabinet, and redundant communication lines and connectors should not collide together to avoid burning the communication network card.
(10) Regularly conduct online testing of the communication load rate of the DCS main system and all related systems connected to the main system. Check the status of redundant master-slave devices, if conditions permit or regularly switch between master-slave devices, and analyze the reasons for the device’s self switching.
(11) Increase configuration readability: Added Chinese descriptions for important configuration pages; Write detailed logic instructions that are consistent with the configuration of important protection systems; Develop test operation cards and ensure they are updated at all times. Standardize DCS configuration operations and minimize significant configuration modifications during unit operation. When configuration is necessary, caution should be exercised and corresponding technical and safety measures should be taken to ensure the safe and stable operation of DCS and the unit.
(12) Regularly restart all human-machine interface stations one by one (recommended for around 2 to 3 months) to eliminate accumulated errors caused by long-term computer operation.