摘要：国外改造用户需要大量通讯,需要我们证明通讯可行.因此,我们提出方案通过转换物理接口,应用Modscan,串口调试工具实现通讯测试.

Proof Test Proposal

Date: 23/02/2012

Version A1.0

Project Description : DCS retrofit for Gas Turbine

Current DCS   : ABB PROCONTROL

Objective:

Proof testing is to ensure the compatibility of the communication between the existing and the new proposed DCS. As request by plant’s owner, due to the control systems of the plant will be retrofit partially, the vendor have to conduct the proof test of the hardware and software interface with existing system in operation smoothly. Importantly, the proof test shall be safety and shall not affect of the existing control system and plant operation.

Content:

1. Hardware:

1.1 Communication card ABB 87TS01-E/R1341:

1.1.1 Application:

The 87TS01 is a coupling module for connecting computers to the PROCONTROL system. Using a serial RS 232c interface, modules version R1341 is suitable to connect a computer, which supports the protocol of the serial interface, to the PROCONTROL station bus. The module’s scope of action includes.

- Listening-in on process data

- Reading registers

- Sending 200 send-location telegrams

- Throughout the entire PROCONTROL system. Data communication with the PROCONTROL system has to be activated from the computer.

1.1.2 Features:

The module allows to load the addresses of up to 230 telegrams to be received under addresses 0…229 of the receive shared memory and up to 200 send location telegrams under addresses 0…199 of the send shared memory.

If there are not enough addresses available for loading, a total of four 87TS01 modules can be connected in parallel via standard interfaces type RS422.

The number of modules which can be used in parallel depends on the application intended with the computer.

1.1.3 Connection diagrams:

The module is to be connected using the specified standard cable sets.

Combining a 87TS01module with a computer on station bus.

The computer can either be connected to connector X1 or connector X2.

By the use of W1 standard cable, it is made sure that an interface type RS 422 is linked to the connector. For operation, either one of module numbers 1…4 may be selected.

1.2  FL2105 conversion interface for proof testing:

1.2.1 Feature:

RS-232 interface and RS-485 / 422 interface bidirectional isolation conversion RS-232 electric larceny serial, no external power supply, and 2000V photoelectric isolation. Support the communication rate of 0 ~ 19.2Kbps, the transmission distance of 1200 meters ( 9.6Kbps ), in support of the 64 node polling communication environment, the signal line 15KV electrostatic protection, 600W / MS lightning protection.

1.2.2 Parameter:

FL2105 isolation conversion, full duplex, half duplex universal, high efficiency of 95% electric larceny serial technique, without the need for external power supply, with industrial terminal block, the standard DB9 hole unique serial, serial protection circuit, can be of electric heating plug, a built-in intelligent module, automatic recognition of RS-485 signal flow, without CTS control, built-in 600W / MS anti lightning protection and antistatic protection 15KV, transparent transmission, baud rate self-adaptive, without the need to change user agreement, industrial design, selection of imported components, all surface mount technology.

? Working voltage: electric serial, without external power supply

? Working current:<15mA

? Baud rate: 0~19.2Kbps

? Communication distance: 0~1.2Km

? Isolation voltage:2500V

? Protection action voltage: 7~8V

? Protection action capacity: 600W/ms

? Electrostatic protection voltage: 15KV

? Working temperature: -45℃~85℃

1.2.3 Instruction:

First Convert RS 422 into RS 232 with FL2105, principle likes below:

4 RTX －－－－－－－－－－－－－－－－－－－－－-5 GND

6 TXD －－－－－－－－－－－－－－－－－－－－－-5 GND

3 RXD— －－－－－－2.2K resistance－－－－－－3 RXD

5 TXD— －－－－－－2.2K resistance－－－－－－2 TXD

Second we connect terminal RS 232 into computer, the other terminal into ABB 87TS01 which transfer data out of PROCONTROL System.

2. Software:

2.1 Application:

ModScan32 software runs under Windows Environment, which use for detecting and communicating with the main equipment supports RTU or the ASCII transmission mode under the MODBUS agreement. Can connect one or more MODBUS slave station devices through the serial port, a modem or network to a PC. You can use ModScan32 to read and modify the data point.

2.2  Instruction:

◇ Open ModScan32 file:

◇ Communication addresses setting:

Fill the block downstairs to set id of communication instrument on ModScan32.

◇ Baud rate setting:

When you click the menu button, you will see the next dialog box.

Parameters setting like this:

1. Communication type selecting: If the port of instrument is COM1, pick COM1 would be ok.

2. Band rate setting: If band rate of instrument is Bps=48, then setting band into 4800, If band rate of instrument is Bps=96, then setting band into 9600.

Other parameter keep default would be ok.

◇ Mode of transmission:

Click protocol selection, then pop-up the dialog box below:

Choose standard RTU signal, click OK.

◇ Length of data setting of Modscan32:

Input length into windows bar, then it will show how many data corresponding.

◇ Type of point selection:

Click tool bar of MODBUS Point Type, it will show Relay status, input state, latch, input register in turn.

Corresponding address of MODBUS is:

◇ PC display mode of parameter selection:

From left to right: Binary, Octal, Decimal, and Hexadecimal.

◇ Other function buttons on menu:

From left to right: New, Open, Save, Continuous, Disconnected, Data definition and etc.

◇ When all parameter have been set right, click OK.

If there is signal transmission, real time data will be obtained.

Testing Result:

As hardware and software are prepared, we can conduct the proof testing on site.

For instance:

1. Read:

1.1 We use SComAssistant23 tool as a simulating instrument on site, then send out a value 1 addressed 00001 by it:

1.2  Read through Modscan32 in which we can find the value 1 in exactly address.

2. Write:

2.1 Write a value 809 into address 00001 with Modscan32 directly:

Press Up date button, check the value on line:

2.2  Read through SComAssistant23 in which we can find the hexadecimal value 0329(equal with decimal value 809) in exactly address 00001:

Risks:

As this proof testing will mainly under manual operation, we list some items about risks in the progress:

1. Short circuit:

When we draw data from PROCONTROL system, we will push interface into PROCONTROL system. The cable connection is like below:

If we link positive and negative terminal together, it may cause some element burning up.

Prevention:

We use convert interface instead of link cable directly, it can highly prevent linking mistakes. Meanwhile the other linking jobs we will use multimeter to check up whether there are unlawful short circuits.

2. Writing mistake:

Writing mistake will cause some equipment false trip. If the equipment is important it will cause series reaction of whole system.

Prevention:

Decline writing operation, and there must be someone with experience to support us on site to insure which point can write into and which cannot.

3. Touching mistake:

If some cables and modules are pulled out by mistake, it will cause un-normal display or many other mistakes.

Prevention:

It’s better to push and pull interface by experience’s engineer onsite, if there are some touching mistake the engineer can recover the cables and modules at once.

Note:

During the testing, we must make sure the safety of equipment on running status. We need onsite engineer who has to be familiar with the existing control system to assist/provide us necessary support for existing information when required. Meanwhile we need all operators on duty watching the whole system carefully, if there are any phenomena un-normal, they must take hand over them at once.

Testing timeline:

We need about two or three hours to finish the proof testing work, if ABB PROCONTROL used standard protocol, then we can retrieve data out of existing system as proposed method.