Woodward 5439-760模块备件

Woodward 5439-751

在平衡状态下，稀薄空气中的二氧化碳浓度
探针膜和电极之间的填充溶液膜
玻璃电极膜等于样品中的玻璃电极膜。这个
薄膜pH值的结果变化通过以下方法测量：
由此产生输出电势的pH电极对
与样品中的二氧化碳浓度相关。喜欢
对于大多数离子选择性电极，8237探针产生
相对于浓度为对数的输出。
在典型情况下
解决方案和校准频率，精度优于
读数的±5%或0.1mgl–1，以较大者为准
实现。
4.2一般操作-图4.1
事件的顺序是：
a） 样品从下方和任何位置进入恒定水头装置
允许过量的水溢出至排水管。
恒压头装置配有一个浮动开关，用以发出信号
“样品外”状态。监视器使用此开关来：
启动“样本不足”警报。
b） 从恒定水头装置的底部开始，取样：
通过电磁阀的常开端口吸入
SV1和SV2由蠕动泵的一个通道驱动。
c） 硫酸试剂通过另一个反应通道被提取
然后与样品混合。这个
管直径的布置应确保获得正确的比例
样品和试剂的浓度。
d） 使酸化样品在恒定条件下反应
释放游离二氧化碳气体的温度条件。
e） 然后，样品进入容器末端的流通盖
进行测量的气体传感探头。
3.设置4个液体处理部分
9
样品
小湾
双通道
蠕动泵
致电子科
排水孔
常数
主管单位
换热器
块
样品
加热器线圈
探查
采样/校准
电磁阀
标准
解决方案1
（低）
反应
线圈
恒压头单元加热器
小地毯
标准
解决方案2
（高）
试剂
解决方案
红色
频道
红色
频道
SV1和SV2
溢流
排水
污染
排水
样品外
浮动开关
从…起
流动池
警卫
管
4液体处理部分
f） 然后，样品通过受污染的排水管连接流向废物。
g） 在校准过程中，监测器通过电磁阀顺序引入两种校准溶液代替样品
阀SV1和SV2。
为了提供正在进行的校准的远程指示，校准继电器被激活。
图4.1流程示意图
10
流动池
加热块
加热器
控制
微处理器单元用户接口
盒
主电源–见图2.3
浓度报警继电器
校准模式继电器
停用继电器
电流输出
采样外继电器
外部的
使用者
连接
外部的
电视连续剧
界面
连接
参考
电极
离子选择性
电极
采样/校准
电磁阀
互连
电缆
样品外
浮动开关
泵和
搅拌器电机
液体处理
部分
保护土
5.电子组
5.1电子布局-图5.1
电子部分包括两个单独的部分：
•右上侧的用户接线盒。
•位于左上侧的微处理器单元。
5.2用户接线盒
用户接线盒包含加热器、电磁阀和继电器
以及所有用户外部连接端子，
串行接口（如安装）除外。
安装后，无需拆除接头
定期更换盒盖。然而，为了辅助任何故障
在查找程序中，p.c.b.上有l.e.d.s.指示
继电器和加热器正在通电。
电源和泵/加热器的开关位于右侧
接线盒的手侧，以及电源指示
灯和电源保险丝——见图2.3。
两个附加保险丝（F2和F3）位于接头内
盒它们连接在24V交流电路中。
5.3微处理器单元
微处理器单元包含模拟输入处理，
微处理器、警报和电流输出生成，以及（如果
安装）串行接口输出。
程序控制、数字和点阵显示、报警
指示和状态l.e.d.s均安装在仪表板的前面板上
微处理器单元。
5.4前面板控制–图5.2
程序控制包括八个触觉膜
开关。这些开关位于铰链门后面
在显示屏下方，可通过螺丝刀操作的锁扣进行访问。在里面
正常操作时，开关用于查看测量的离子
浓度值，启动手动校准，或激活
“警报保持”设施。
编程时，开关用于按顺序通过
如详细所述的编程过程。该程序载于
输入、电流输出、报警、实时编程页面
时钟和监视器校准。每个节目页面包含：
程序功能，其值或参数为：
节目

Woodward 5439-751

Woodward 5439-751

At equilibrium, the concentration of carbon dioxide in the thin film of filling solution between the probe membrane and the glass electrode membrane equals that in the sample. The resultant change in pH value of the thin film is measured by the pH electrode pair which thus develops an output potential related to the carbon dioxide concentration in the sample. Like most ion-selective electrodes, the 8237 Probe produces an output which is logarithmic with respect to concentration. Under typical circumstances, with appropriate standard solutions and calibration frequencies, accuracies better than ±5% of reading or 0.1mgl–1 whichever is the greater, can be achieved. 4.2 General Operation – Fig. 4.1 The sequence of events is: a) The sample enters the constant head unit from below and any excess is allowed to overflow to drain. The constant head unit is fitted with a float switch to signal an 'Out of Sample' condition. This switch is used by the monitor to initiate the 'Out of Sample' alarm. b) From the bottom of the constant head unit the sample is drawn through the normally open ports of the solenoid valves SV1 and SV2 by one channel of the peristaltic pump. c) The sulfuric acid reagent is drawn through another channel of the peristaltic pump, and is then mixed with the sample. The tube diameters are arranged so as to obtain the correct ratio of sample and reagent. d) The acidified sample is allowed to react under constant temperature conditions to release free carbon dioxide gas. e) The sample then enters a flow-through cap at the end of the gas sensing probe where the measurement takes place. 3 SETTING UP 4 LIQUID HANDLING SECTION 9 Sample Inlet Two Channel Peristaltic Pump To Electronics Section Drain via Constant Head Unit Heat Exchanger Block Sample Heater Coil Probe Sample / Calibrate Solenoid Valves Standard Solution 1 (Low) Reaction Coil Constant Head Unit Heater Mat Standard Solution 2 (High) Reagent Solution Red Channel Red Channel SV1 SV2 Overflow Drain Contaminated Drain Out of Sample Float Switch From Flowcell Guard Tubes 4 LIQUID HANDLING SECTION f) The sample then flows to waste via the contaminated drain connection. g) During a calibration, the monitor introduces two calibration solutions sequentially in place of the sample by means of the solenoid valves SV1 and SV2. To provide remote indication of a calibration in progress, the calibration relay is activated. Fig. 4.1 Flow Schematic 10 Flow Cell Heater Block Heater Control Microprocessor Unit User Junction Box Mains Supply – see Fig. 2.3 Concentration Alarm Relays Calibration Mode Relay Out of Service Relay Current Outputs Out of Sample Relay External User Connections External Serial Interface Connections Reference Electrode Ion-Selective Electrode Sample/Calibrate Soleniod Valves Interconnection Cables Out of Sample Float Switch Pump and Stirrer Motors Liquid Handling Section Protective Earth 5 ELECTRONICS SECTION 5.1 Electronic Layout – Fig. 5.1 The electronic section comprises two separate sections: • The User Junction Box at the top right hand side. • The Microprocessor Unit at the top left hand side. 5.2 User Junction Box The User Junction Box contains the relays for the heater, solenoid valves and alarms, and all the user external connection terminals, with the exception of the serial interface (if fitted). Once installed there should be no need to remove the junction box cover on a regular basis. However, to assist in any fault finding procedure, there are l.e.d.s on the p.c.b. to indicate if the relays and heater are being energised. Switches for the mains and pump/heater are situated on the right hand side of the junction box, together with a mains indication lamp and mains fuse – see Fig. 2.3. Two additional fuses (F2 and F3) are located within the junction box. These are connected in the 24V AC circuits. 5.3 Microprocessor Unit The Microprocessor Unit contains the analogue input processing, microprocessor, alarm and current output generation, and (if fitted) the serial interface output. The programme controls, digital and dot-matrix displays, alarm indication and status l.e.d.s are all mounted on the front panel of the microprocessor unit. 5.4 Front Panel Controls – Fig. 5.2 The programme controls comprise eight tactile membrane switches. These switches are situated behind a hinged door below the display, access is via a screwdriver-operated catch. In normal operation the switches are used to view the measured ion concentration value, initiate a manual calibration, or to activate the 'alarm hold' facility. When programming, the switches are used to sequence through a programming procedure as detailed. The procedure is set out in programming pages for Input, Current Output, Alarms, Real Time Clock and Monitor Calibration. Each programme page contains the programme functions, the values or parameters of which are progra