电脑技术员英语自我评价( 四 ) 「问人人知识网」

But I have a lot of knowledge about the thermal aspects of our system and are particularly interested in it and have a thorough understanding of it.While at the same time learn from their own, but also assume responsibility for preaching to other operational personnel. Our company's hot water network project is the use of computer monitoring system to achieve hot water production and operation of the comprehensive monitoring of the data. Its main components include the controller, input and output modules and monitoring stations. Our company has 18 sets of SCAN3000 / S9000 distributed control system (DCS), which has the functions of hot water network operation loop control, data acquisition, data communication, centralized information management And operation display functions. It is equipped with two S9000 controllers, and another 12 single-loop controller (Honewell UDC3300), as the control loop redundancy controller and emergency hand terminal. UDC as a backup hand-held device can DCS in the event of failure, the control loop to control. With easy to operate, programmable, high stability characteristics.
DCS system and UDC can achieve between the non-disturbance switch, to ensure the stability of the system operation. S9000 controller through the DVC communication port of the DMC communication circuit and single-loop controller to achieve communication; through the MGTSTA communication port and the system monitoring station communication card connected. With these control systems, usually a variety of parameters of the regulation and personnel labor will have a multiplier effect. These control systems are made up of measuring elements (temperature transmitters, pressure transmitters, differential pressure transmitters), control elements (S9000, UDC), actuators (regulators, etc.). Control flow is such that the scene collects data from a meter, the transmitter sends 4-20mA signal to the S9000 (that is often said DCS), 1-5V signal to the UDC. And then issued by the S9000 or UDC 4-20mA signal (UDC series with 250Ω resistor, 1-5V signal to 4-20mA signal) to adjust the actuator. In this process, the instrument's power supply from the two Siemens 24V DC power supply (the two power supply each other spare), the power to the distributor, and then by the electrical distribution to a primary meter power supply (the middle of electrical distribution in order to meter repair , Will not have a short circuit, and damage the DC power supply). DCS or UDC receives the signal that is displayed on the CRT or UDC own screen. DCS or UDC control signal to the impedance converter, distributor, the isolation module or isolated relay relay to the executive control.
Isolation module is through the analog signal, that is, continuous control signal 4-20mA, such as the valve opening, level control; and isolation relay is the switch signal to the DCS, such as temperature switches, pressure switches and pumps Start, stop state, etc. (plus isolation module, isolation relay is to isolate strong signals, so as not to S9000 in the loop control card burned).