Teledyne HFC-E-202 Operation with External Devices, High Pressure Operation, Blending of Gases

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periodically during normal operation. Zero adjustment is required if there is a change in ambient temperature, or vertical orientation of the Flowmeter/controller.

2.6.3. High Pressure Operation

When operating at high pressure, the increased density of gas will cause natural convection to flow through the sensor tube if the instrument is not mounted in a level position. This natural convection flow will be proportional to the system pressure. This will be seen as a shift in the zero flow output that is directly proportional to the system pressure.

2.6.4. Blending of Gases

In the blending of two gases, it is possible to maintain a fixed ratio of one gas to another. In this case, the output of one flow controller is used as the reference voltage for the set point potentiometer of a second flow controller. The set point potentiometer then provides a control signal that is proportional to the output signal of the first flow controller, and hence controls the flow rate of the second gas as a percentage of the flow rate of the first gas.

EXAMPLE: Flow controller A has 0-10 slpm range with a 5.00 volt output at full scale. Flow controller B has 0-1 slpm range with a 5.00 volt output at full scale. If flow controller A is set at 8 slpm, its output voltage would be 4.00 volts (8 slpm/10 slpm x 5.00 volts = 4.00 volts). If the output signal from flow controller A is connected to the command potentiometer of flow controller B, it then becomes a variable reference voltage for flow controller B proportional to the flow rate of flow controller A.

If the set point potentiometer of flow controller B is set at 50% of full scale, and the reference voltage from flow controller A is 4.00, then the command signal going to flow controller B would be 2.00 volts (4.00 volts x 50.0% = 2.00 volts). The flow of gas through flow controller B is then controlled at 0.4 slpm (2.00 volts/5.00 volts x 1 slpm = 0.4 slpm).

The ratio of the two gases is 20:1 (8 slpm/0.4 slpm). The % mixture of gas A is 95.2 (8slpm/84slpm and the % mixture of gas B is 4.8% (0.4 slpm/8.4 slpm).

Should the flow of flow controller A drop to 7.8 slpm, flow controller B would drop to 0.39 slpm, hence maintaining the same ratio of the mixture. (7.8 slpm/10 slpm x 5v = 3.90v x 50% = 1.95v; 1.95v/5.00v x 1 slpm = 3.9 slpm; 7.8 slpm: 0.39 slpm = 20:1)

2.7.Operation with External Devices

2.7.1. Operation with a Hastings power supply.

There are two controls for each flow controller connected to a Hastings power supply. A switch labeled “OPEN; AUTO; CLOSED” (valve over ride THPS 400 only) and a potentiometer labeled “COMMAND”. For normal operation, the valve over ride switch will be in the “AUTO” position. The “CLOSE” position removes all power from the valve, shutting off flow regardless of the command pot setting. The “OPEN” position applies full available valve voltage to the valve, causing it to open, regardless of the command pot setting. The “OPEN” position is useful for purging systems. It is recommended that the valve over ride switch not be left in this position for extended periods of time, with no flow through the controller, as a small positive zero shift may be observed.

The “COMMAND” pot adjusts the Analog command signal sent to the flow controller. The setting for each controller connected to the power supply can be observed. (Depending on how the power supply was set up, the display could indicate in flow units or percent of full scale).

2.7.2. Operation with a power supply other than a Hastings.

The flow controller must be connected to the power source as specified in section 2.6. In general, a 0-5 VDC command signal proportional to the intended flow (0 volts = zero flow; 5 volts = 100% of rated flow) must be applied to pin A of the “Edge” connector. A 0-5 VDC signal proportional to the flow rate through the instrument will be present on pin 3 of the “Edge” connector. The control mode is selected via pin J of the “Edge” connector. Apply +15 volts for full open, -15 volts for closed and allow pin J to float for flow proportional to the command voltage. Refer to your power supply manual for the specifics of implementing these parameters.

HFM-E-200/HFC-E-202

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Contents Teledyne Hastings Manual Print History Table of Contents Installation and Operation FeaturesSpecifications Swagelok, 1/8 Swagelok, VCR, VCOInterconnecting Cables Other AccessoriesHastings Power supplies Optional 4-20 mA Current OutputReceiving Inspection Power RequirementsOutput Signal Mechanical ConnectionsElectrical Connections Operating Conditions OperationZero Check Operation with External Devices Operation with a Hastings power supplyOperation with a power supply other than a Hastings High Pressure OperationOperation with an external sensor. Fig Range ChangingSoft Start Sensor Theory of OperationOverall Functional Description ElectronicsShunt Valve Authorized Maintenance MaintenanceTroubleshooting Adjustments Calibration Procedure FigureMiscellaneous adjustments Printed Circuit Board ReplacementSensor Replacement Inlet Removal0014 Q HFC-E-202 OrificeReplacement Parts Conversion Factor Table BF3C2H7N C3H8O SO2 Warranty Repair Policy Non-Warranty Repair PolicyDrawings HFM-E-200/HFC-E-202 HFM-E-200/HFC-E-202 HFM-E-200/HFC-E-202 HFM-E-200/HFC-E-202 HFM-E-200/HFC-E-202

HFC-E-202, HFM-E-200 specifications

Teledyne HFC-E-202 and HFM-E-200 are advanced flow meters designed to provide precise measurement and monitoring of gas and liquid flows in various industrial applications. Both devices are engineered to meet the demands of sectors such as petrochemicals, pharmaceuticals, and food and beverage, where accuracy and reliability are paramount.

The Teledyne HFC-E-202 is a highly sensitive flow meter that utilizes a thermal mass flow measurement technology. This technology enables the HFC-E-202 to accurately measure the mass flow rate of gases regardless of temperature and pressure conditions. One of its key features is its ability to provide high precision and fast response times, making it suitable for applications that require immediate data feedback. The device is also equipped with advanced diagnostics that allow users to monitor the health of the system and identify potential issues before they escalate.

On the other hand, the HFM-E-200 is particularly renowned for its versatility in measuring both gas and liquid flows. It employs differential pressure technology, which is highly effective in a wide range of operating conditions. The HFM-E-200 incorporates a robust design that can withstand harsh environments, ensuring longevity and reliability. Its user-friendly interface allows for easy configuration and monitoring, catering to both novice and experienced technicians.

Both flow meters feature digital output options, facilitating seamless integration with existing control systems. This enables real-time data acquisition and monitoring, enhancing process control and efficiency. Furthermore, their compact design minimizes installation space, allowing for easy placement in tight operational areas.

In terms of safety and compliance, both the HFC-E-202 and HFM-E-200 are designed to meet strict industry standards, ensuring they can be deployed in critical applications without compromising safety.

In conclusion, Teledyne HFC-E-202 and HFM-E-200 flow meters stand out due to their innovative technologies, accuracy, and durability. Their unique features position them as essential tools for a variety of industrial sectors, enhancing operational efficiency and ensuring reliable fluid flow measurement. With Teledyne’s commitment to quality and innovation, users can trust that these devices will meet their demands both now and in the future.
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