SCS - PLC program control system upgrade

1 the problems existing in the system of the SCS that wujing thermal power plant in the early 1990 s of 2 units of 300 mw thermal power unit, the SCS control system has been used since it was put up to now. The system mainly control six big fan, air preheater, feed water pump, condensate pump, vacuum pump, hydrophobic system and other related chain and protection function. The MODICON - the original system Series, 984 series PLC, to hot standby configuration of two CPU, 9 by remote station more than 2700 points, 35 frame, constructed the system I/O signal. After years of operation, mainly exist the following problems: ( 1) Equipment aging, to set up checked posts a performance is not stable. Already stop production, the series of control card parts spare parts can not purchase. （ 2) System configuration is not reasonable. The original control system with single power card with remote station set up, and under the remote station concatenated 2 ~ 3 I/O rack, if the remote station power or communications failure, will lead to the remote station and all lost, with the I/O signals of the consequence is very serious. （ 3) The original SCS - PLC control system and DCS communication mode for MB. By the main communication card and spare communication card parts each led road 1 MB telecommunication lines first a DCS communication card on a side. However, when the PLC CPU side after hot standby switching, MB communication also subsequently switch, but the upper side of DCS communication card only in DCS communication card parts failure would switch, not because a system communication switching and switching. So, the actual working condition is when PLC side hot standby switch, upper side of DCS system cannot follow PLC controller MB communication switch and switch, causing communication interrupt. （ 4) Programming software for WIN98 MODSOFT software platform, has been unable to adapt to the request of the now commonly used operating software, backup is very inconvenient. Figure 1 original SCS system local topology 2 SCS system hardware upgrades the original SCS system adopts MODICON 984 series CPU as a local station, such as P890, P810 power communication module and the way of the coaxial cable of the build up of nine remote station, 35 frame, more than 2700 point I/O signals. I/O modules for the standard of ac 220 v input module, dc 24 v input/output module, relay output module and so on. So, module updates to the QUANTUM series, basic for the replacement of one to one correspondence. Local station adopts 140 cpu534 configuration, I/O module with 140 series corresponding module. Due to QUANTUM series motherboard maximum 16 slot, the original MODICOM 984 series motherboard maximum 10 slot, by incorporating some of the original configuration card after a less rack, the original 35 rack fell to 29 frame, saving a lot of space. 3 SCS system configuration optimization and power supply redundancy configuration the SCS system with single power card with remote station set up, and under the remote station concatenated 2 ~ 3 I/OP frame. The configuration stability is poorer. Once the power card fail, may cause the frame loss of electricity, and in a series circuit of 2 ~ 3 I/O rack all losing electricity, the rack on the I/O card of I/O spot with all lost, have serious consequences. Because our factory have SCS system power card fails, causing important auxiliary machine, even the MFT incidents. Considering the SCS system in the important position of main control system, the upgrade will SCS system configuration optimization and configuration of redundant power supplies. Configuration optimization is 2 ~ 3 original concatenated connected I/O rack independently configured for remote station, each frame in power communication failure does not affect the normal work of the other frame. In addition, the original single remote station power supply configuration upgrade for QUENTUM series redundant power supply configuration. Card when one power supply fails, the redundant power supply will be independent for power supply, rack and display the failure indicator, maintenance personnel replacement power card. 4 solve the problem of SCS system communicate with DCS system in power switch the SCS local host and hot standby each have a MB telecommunication lines connected to DCS main for MB communication card. If SCS main standby switching, in which the original host communications MB by switching to the hot standby stand MB telecommunication lines, and superior DCS MB communication card and, therefore, is not switch, led to the suspension of SCS and DCS communication. Through this upgrade, the original MB communication way to upgrade for MB + communications, the main and hot standby MB + telecommunication lines synthesis via the MB + branch all the way to the DCS, then by the MB + branch is divided into two road is connected to the main case of MB + communication card on DCS. Due to the side of SCS, main/backup MB + communication card in the same address, DCS side the address can be configured in MB + communication protocol, whatever Lord for SCS side switch, DCS side can be through the MB + spliter SCS side in the work to find the PLC to communicate with the local station. Also, if the DCS side of main equipment switched, but also by MB + branch still keep contact with SS communication. 5 SCS programming software upgrades and upper software with the SCS is a product of the 1980 s MODSOFT programming software. The product for the application of 16 DOS software, cannot be installed on the existing 32-bit operating system ( Such as WINXP) , still use 3 inch disk backup, is neither easy nor reliable. And MODSOFT can only as a language LL984 programming tools, function relatively single, programmer for the communication with PLC controller is not very stable MB communication mode, data traffic is bigger, appear to be slow.
Most places have a few choices when it comes to programmable control systems plc manufacturers distributors, but it can sometimes be difficult to find the right supplier for your needs. The quality of plc manufacturers is critical to plc controller price.
Shenzhen Coolmay Technology Co., Ltd. take prudent risks and work together to assure our success and profitability in the future.
Turn to Shenzhen Coolmay Technology Co., Ltd. if you are looking for premier programmable control systems solution, affordable packages, and quality plc manufacturers products! We produce wide series of high quality, first-class , and provide professional plc manufacturers services at great prices.