Sierra 860, 840, 830 instruction manual Motor-Operated Rotary Valve Controllers

Models: 840 830 860

1 74
Download 74 pages 60.88 Kb
Page 30
Image 30

Series 830/840/860 Instruction Manual

Chapter 3 Operation

 

 

Motor-Operated Rotary Valve Controllers

When the transducer is installed and the system has undergone a complete leak check:

1.Make sure the valve set point is zero before applying power.

2.Apply power. Allow thirty minutes of warm-up time. (When power is first applied, the output signal from the transducer remains fixed at a much higher than normal level until the sen- sor warms up to its normal operating temperature range.)

3.Turn on the gas supply. Verify that no flow exists. Perform an initial zero output check (only required for first-time start ups). Set flow to zero. Connect a digital multimeter to V+out (4-20 mA out) and COM terminals.

4.Check the reading. If it is not within ±10 mV (±0.10 mA) of zero, adjust the zero potentiometer to zero the transducer. (The zero pot is located behind the upper metal button on the side of the transducer or behind the swing-out plastic door.)

5.Adjust the controller set point to the desired flow rate.

All motor-operated rotary valves seek a “deadband” where the flow is identical to the set point within specified tolerances. Keep this in mind when checking the instrument’s performance. For in- stance, a 100 scfm flow controller may have a set point of 2.500 volts (50 scfm) and a flow indication of 2.550 volts (51 scfm). This controller is working correctly, since the difference between the flow and the set point is within 1 scfm, which is the specified accu- racy of ±1% of full scale (0.01 x 100 scfm = 1 scfm). The width of the deadband varies with the valve size and range of each control- ler.

During operation, the motor runs only when it needs to. If the pres- sure differential across the valve is insufficient to obtain set point, the valve will open fully and the motor will cease to run. Con- versely, if the set point is zero, the valve will close, and the motor will cease to run. In either case, there will be no control action. Check for adequate pressure differential and that set point command voltage is present at the motor operator connector.

IM-83/84/86-H

3-3

Page 30
Image 30
Sierra 860, 840, 830 instruction manual Motor-Operated Rotary Valve Controllers

840, 830, 860 specifications

The Sierra 860, 830, and 840 are a series of rugged outdoor laptops designed for professionals who require reliable and powerful computing solutions in challenging environments. These laptops combine advanced technologies and robust construction to meet the demands of various fields, including engineering, military, field services, and outdoor research.

One of the standout features of the Sierra series is its rugged design. Constructed with military-grade materials, these laptops are highly resistant to shock, vibration, and extreme temperatures. They have undergone rigorous testing according to MIL-STD-810G standards, which ensures they can withstand harsh conditions whether in the field or during transport. Additionally, the IP65 rating guarantees protection against dust and water exposure, making them invaluable for professionals working in inclement weather or dusty environments.

The Sierra 860, 830, and 840 are powered by high-performance processors, delivering fast and efficient processing capabilities. Equipped with the latest Intel Core processors, including i5 and i7 options, these laptops can handle demanding applications and multitasking with ease. The robust memory options, ranging from 8GB to 32GB, ensure smooth performance for memory-intensive tasks.

Display quality is another critical aspect of these laptops. The Sierra series features high-resolution screens that offer bright, vivid colors and sharp details, making them ideal for tasks requiring precision, such as drafting and design work. The touch-enabled displays enhance user interaction, providing convenience in outdoor settings where traditional input methods may be challenging.

The Sierra laptops also include a comprehensive array of connectivity options, ensuring seamless integration with various devices. With multiple USB ports, HDMI output, and optional mobile broadband, users can easily connect to peripherals, transfer data, and maintain communication. The inclusion of enterprise-level security features, including biometric scanners and encrypted storage, ensures sensitive data remains protected.

Battery life is another crucial factor in fieldwork, and the Sierra series excels in this area. With long-lasting batteries, these laptops can operate for extended periods without needing a recharge, making them perfect for long outdoor excursions or remote job sites.

In summary, the Sierra 860, 830, and 840 combine ruggedness, high performance, and extensive connectivity options, making them exceptional computing solutions for professionals in various challenging environments. Their advanced technologies and robust constructions ensure they can tackle the demands of outdoor work while maintaining reliability and efficiency.