Abstract : This article introduces the technical transformation of the old refrigeration unit's electrical system by organically combining the existing Ex-Ⅱ type paperless recorder with the JP6C-T9/J9-45 frequency converter at Yong'an Forestry Chemical Plant, realizing intelligent control and giving new life to conventional electrical equipment.
1. System Overview
1.1 System Command and Control Center
The control center of this system is housed in the Ex-Ⅱ-06-R-CU50-6-P-C (with upper and lower limits) paperless recorder. This recorder is a novel concept recorder jointly developed by Shanghai Dahua Instrument Factory and the National University of Defense Technology. It can process various input signals requiring monitoring and recording in the industrial field through its onboard CPU, storing the monitored signal data in a large-capacity built-in memory chip for easy retrieval. The recorder features a fully Chinese-language menu operation, a user-friendly interface, and simple operation. It also includes functions such as password setting, clock adjustment, 6-channel selection, and parameter setting. This system utilizes the recorder's original 6 independent alarm contacts as command signals for gear shifting (neutral, I, II, III, IV), start, run, and stop.
1.2 System Control Principle
1.2.1 According to the requirements of the production process, it can be...
The material reaction temperature is set to four temperature ranges: t0-t1, t1-t2, t2-t3, and t3, plus a temperature switching point (t0) for shutdown. The EX-type paperless recorder issues a "Level I" command in the t0-t2 range; a "Level II" command in the t0-t2 range; a "Level II" command in the t2-t3 range; and a "Level IV" command when the temperature exceeds t0, and vice versa.
The gear shifting commands issued by the EX-type paperless recorder are all executed by four relays and four electromagnetic armatures, which complete the specific tasks of "shifting up", "shifting down", and returning to "neutral".
When the chiller needs to be started, simply close the air switch "DK", and the system will enter the inverter/32-frequency automatic identification and conversion circuit, adhering to the principle of "inverter priority".
For details, please click: Combined Application of Ex-11 Paperless Recorder and Frequency Conversion Technology
