Introduction to Transmitters used in Process Control

Flow transmitter (ModMag)

Transmitters are process control field devices. They receive input from a connected process sensor, then convert the sensor signal to an output signal using a transmission protocol. The output signal is passed to a monitoring, control, or decision device for use in documenting, regulating, or monitoring a process or operation.

In general, transmitters accomplish three steps, including converting the initial signal twice. The first step is the initial conversion which alters the input signal to make it linear. After an amplification of the converted signal, the second conversion changes the signal into either a standard electrical or pneumatic output signal that can be utilized by receiving instruments and devices. The third and final step is the actual output of the electrical or pneumatic signal to utilization equipment - controllers, PLC, recorder, etc.

Transmitters are available for almost every measured parameter in process control, and are often referred to according to the process condition which they measure. Some examples.

• Pressure transmitters
• Temperature transmitters
• Flow transmitters
• Level transmitters
• Vibration transmitters
• Current, voltage & power transmitters
• PH, conductivity, dissolved gas transmitters, etc. 
• Consistency

Consistency Transmitter(TECO)

Output signals from transmitters, when electrical, often are either voltage (1-5 or 2-10 volts DC) or current (4-20 mA). Power requirements can vary among products, but are often 110/220 VAC or 24 VDC.  Low power consumption by electrical transmitters can permit some units to be "loop powered", operating from the voltage applied to the output current loop. These devices are also called "two-wire transmitters" because only two conductors are connected to the unit. Unlike the two wire system which only needs two wires to power the transmitter and carry the analog signal output, the four-wire system requires four separate conductors, with one pair serving as the power supply to the unit and a separate pair providing the output signal path. Pneumatic transmitters, while still in use, are continuously being supplanted by electrical units that provide adequate levels of safety and functionality in environments previously only served by pneumatic units.

Pressure
Transmitter
(ifm)

Many transmitters are provided with higher order functions in addition to merely converting an input signal to an output signal. On board displays, keypads, Bluetooth connectivity, and a host of industry standard communication protocols can also be had as an integral part of many process transmitters. Other functions that provide alarm or safety action are more frequently part of the transmitter package, as well.

Wireless transmitters are also available, with some operating from battery power and negating the need for any wired connection at all. Process transmitters have evolved from simple signal conversion devices to higher functioning, efficient, easy to apply and maintain instruments utilized for providing input to process control systems.

To lean more about instrumentation and control, visit http://www.teco-inc.com or call Thompson Equipment at 800-528-8997.

Valve Automation Professionals Will Save You Time and Money on Your Next Industrial Valve Project

Local Distributors and Reps provide great value when
working on automated valve projects.

Local distributors and representatives who sell industrial valves, actuators and controls also provide services and equipment that will save you time, money, and help you achieve a better outcome for the entire project.

Projects requiring engineered valve systems are best completed and accomplished through the proper selection and application of the valves, actuators, positioners, limit switches and other associated components. A great resource exists, ready to provide a high level of technical knowledge and assistance, that can be easily tapped to help you with your project - the valve automation sales professional.

Consider a few of the things the valve automation professional brings to your project:

Product Knowledge: Valve automation professionals are current on product offerings, proper application technique, and product capabilities. They also posses  information on future product obsolescence and upcoming new designs. This type of information is not generally accessible to the public via the Internet.

Experience: As a project engineer, you may be treading on new ground regarding some aspects of your current valve system design assignment. There can be real benefit in connecting to an experienced and highly knowledgable source, with past exposure to your current challenges.

Access: Through a valve automation professional, you may be able to establish a connection to “behind the scenes” manufacturer contacts with essential information not publicly available. The rep knows people at the factories, a well as at other valve related companies, who can provide quick and accurate answers to your valve automation related questions.

Of course, any valve actuation or automation solution proposed are likely to be based upon the products sold by the representative. That is where considering and evaluating the benefits of any solution becomes part of achieving the best project outcome.

Develop a professional, mutually beneficial relationship with a local valve automation professional to make your design job go after, more efficiently, and more cost effective. Their success is tied to your success, and they are eager to help you.

The Magmeter Zone - Don't Let Your Flow Meters Die Here

Don't let this happen to your old flowmeters! 

Here's a video parody of the popular TV show "The Twilight Zone", only here it's the "Magmeter Zone", where old, worn out magmeters go to die. From the creative minds at TECO ... humor in magnetic flowmeters - who woulda thunk it?  Enjoy!