Emerson Process Management 430 DO Section Troubleshooting, Temperature Resistance Chart

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MODEL 430 DO

SECTION 4.0

 

TROUBLESHOOTING

SECTION 4.0

TROUBLESHOOTING

4.1GENERAL. This section contains troubleshooting data for the Model 430 Sensor Assembly.

4.2TROUBLESHOOTING THE MODEL 430 DISSOLVED OXYGEN SENSOR. The majority of problems encountered in DO systems are because the sensor is either improperly maintained or has an inter- nal leakage causing improper temperature compen- sator resistance and high impedance current paths between elements of the sensor.

Disassemble the sensor completely by unscrewing the reservoir retainer and pulling the reservoir housing assembly straight out (refer to Figure 5-2). The mem- brane may have dried onto the gold cathode. Soak this loose with water as scraping will damage the gold tip. Clean all the parts with clean water and dry them. Check for visible damage (i.e., cracks, deep cuts, bro- ken silver wires). Perform the following checks with an ohmmeter. Check T.C. resistance between the green and white wires. It should be 100K ohms at 25°C or per the Temperature/Resistance Chart. Check continuity between the red wire and the silver anode, and between the black wire and the gold cathode (be care- ful not to scratch the gold). Perform a high meg check between the following (100 meg ohms minimum): Shield to Black or Red or Green. If everything checks O.K., the sensor should function after a proper recharge. If the silver anode appears oxidized, it may be cleaned with wet or dry 400 sandpaper. Also brush the gold tip two or three times with the 400 sandpaper in one direction only. Follow the recharge directions in Section 3.2.

4.3BENCH TESTING. Soak the electrode for 24 hours with polarizing voltage applied (instrument), then air calibrate to check for a response.

CAUTION

Care should be taken not to damage the membrane made of “Teflon”.

1.Low readings and inability to calibrate are generally the result of a coated membrane and usually can be restored to service by cleaning the sensor. Clean a coated mem- brane by gently wiping the membrane with a soft cloth or tissue.

1Reg. U.S. Pat. Office for du Pont’s fluorocarbon resins.

2.Readings offscale and inability to calibrate are usually caused by a damaged mem- brane. If this is the case, replace the mem- brane.

3.To check the membrane made of “Teflon”, connect the negative (—) lead of an ohm- meter to the cathode (black) lead and place water saturated with salt on the membrane. Touch the positive (+) lead to the water. The meter should read open (100 megohms or more). If the meter indi- cates a short (less than 100 megohms), replace the membrane (refer to Section 3.2).

4.To check the resistance of the temperature compensator, connect an ohmmeter to the green and white leads of the sensor. The resistance should be as indicated at the temperature listed below: If the resistance as specified above cannot be achieved, replace the sensor (Figure 5-2).

Temperature Resistance Chart

TEMPERATURE

RESISTANCE (ohms)

 

 

0°C

371.40K

 

 

10°C

214.50K

 

 

20°C

128 00K

 

 

25°C

100.00K

 

 

30°C

78.00K

 

 

40°C

49.80K

 

 

50°C

32.36K

 

 

5.To check for shorted sensor leads, meas- ure the resistance between one tempera- ture compensator wire (green or white) and the cathode (black) lead and anode (red) lead. The meter should indicate an open circuit (100 megohms or more). Repeat the measurement using the other temperature compensator wire. If the sensor shows a short circuit, the sensor is defective and should be replaced.

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Contents Dissolved Oxygen Sensor Hazardous Area Installation Essential InstructionsTable of Contents Model Dissolved OxygenTable of Contents List of Figures List of TablesSection General Description and Specifications Features and ApplicationsTemperature Compensation Specifications Process ConnectionWetted Materials Housing PVC Membrane Teflon 4004301940043018 Optional Mounting BracketModel Section Installation Electrode Connections Sensor Lead Model 1181DOCodes and 01 and 02 Flow Through Installation 40043001Code 03 Sensor Dimensions 40043002Page Section Maintenance Do not Remove ITSection Troubleshooting Temperature Resistance ChartSection Parts Lists 4004505240043016 Part Number Description Qty40043015 40043017 NON Warranty REPAIR. Contact Factory For Authorization Section Return of MaterialEUROPE, Middle EAST, and Africa Americas HeadquartersASIA-PACIFIC Additional Sales OfficesReturn of Materials Request Sensor or Circuit Board onlyPage Warranty Specifications subject to change without notice

430 DO specifications

Emerson Process Management has long been a pioneer in the field of automation and instrumentation, and one of its standout products is the 430 DO, a digital output module widely used in various industrial applications. The 430 DO is engineered to facilitate increased efficiency, reliability, and flexibility in process management systems.

One of the main features of the 430 DO is its ability to support a range of output configurations. It typically offers multiple channels, allowing operators to control various field devices simultaneously. This high-density output capability makes it ideal for applications where space and resources are constrained.

The module utilizes advanced digital signal processing technology, which enhances its performance and responsiveness. This technology ensures that the 430 DO can handle robust signal processing, leading to improved speed and accuracy in control processes. Moreover, the module complies with the industry standards for electromagnetic compatibility (EMC), ensuring minimal interference and enhanced operational integrity in diverse environments.

In terms of connectivity, the 430 DO is designed to integrate seamlessly within Emerson's DeltaV™ control system, enabling quick deployment and straightforward configuration. The use of an intuitive interface simplifies setup and allows operators to quickly adapt to changing process requirements. Additionally, the module supports extensive communication protocols, which facilitates interoperability with various devices and systems, enhancing overall operational versatility.

Another notable characteristic of the 430 DO is its built-in diagnostic capabilities. Real-time monitoring offers insights into the status and health of the outputs, allowing for proactive maintenance actions to be taken before potential failures occur. This feature not only enhances operational reliability but also contributes to reduced downtime and maintenance costs.

Safety is paramount in any industrial environment, and the 430 DO module incorporates safety features that comply with international safety standards. These features enable fail-safe operations, ensuring that process integrity is maintained even in the event of an unexpected shutdown or fault.

In summary, Emerson Process Management's 430 DO digital output module stands out for its versatile output configurations, advanced signal processing technologies, seamless integration with control systems, built-in diagnostics, and emphasis on safety. Its design reflects Emerson's commitment to providing tools that enhance performance and streamline operations in the ever-evolving landscape of industrial automation. With the 430 DO, organizations can expect improved efficiency and reliability in their process management systems.
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