Transmitters and transducers
All electronic pressure instrumentation transducers and transmitters convert an applied pressure into an electrical signal. This signal is sent to computers, chart recorders, digital panel meters or other PLC (programmable logic controllers) devices. That is, they interpret this electrical signal and use it to display, record and/or change the pressure in the system being monitored. The most common signal used in industrial applications is a 2-wire, 4-20 milliampere(mA) current loop.
Other signals used include:
- 1-5 volts
- 5 volts
- 0-10 volts (3-wire system)
- 0-100 millivolts (4-wire system)
In many cases the display device in the transmitter can accept more than one type of output. For example 4-20 mA or 0-5 volts.
Noshok and Winters manufacture a wide variety of 4-20 mA output pressure transmitters; they have even developed special pressure transmitters for the food, petrochemical, chemical and water treatment industries.
Characteristics of pressure transmitters
The characteristic of Noshok and Winters pressure transmitters is that they can be supplied for use in hazardous areas:
- FM or CSA approved
- By convention, a pressure transmitter provides a mA output, while a pressure transducer provides a voltage output.
Many users refer to transmitters and transducers without differentiation; this can create some confusion. For this reason it is convenient to note that general purpose pressure sensors are most often referred to as pressure transducers.
Noshok and Winters Pressure Transmitters
Noshok and Winters pressure transmitters are fixed range devices and are described in part by pressure range and output type.
- A transmitter with a 0-100 psi range and 4-20 mA output should produce a 4 mA output at zero pressure and 20 mA at 100 psi.
- Since the output of the transmitter is linear, i.e., it is directly related to the applied pressure; at 25 psi the output will be 8 mA, at 50 psi, 12 mA, and at 75 psi, 16 mA (equation of a straight line).
- If the device reading this mA signal is a programmable board gauge, it can convert the 4-20 mA signal to 0-100 psi and display the pressure on the digital readout. Since 4-20 mA is consistent, the gauge can be programmed to display any of the desired units.
- If a BAR reading is required, the gauge is programmed to display 0 bar at 4 mA and 6.89 bar at 20 mA. The meter circuit completes all other calculations automatically.
Noshok and Winters pressure transducers and transmitters are designed for long and reliable operation in industrial plants with corrosive environments. Most models are constructed of stainless steel and circuitry, which is always protected against moisture and vibration. All are calibrated and tested before delivery. A variety of options are available on most models to meet specific needs.
Noshok and Winters are manufacturers of compact and configurable range type pressure transmitters (known as process transmitters). State-of-the-art technology is used in their manufacture.
The only sensors used are:
- Thin film
All transmitters are manufactured in Germany and Canada, tested one by one to ensure accuracy and meet the highest quality standards, with excellent price/performance ratio.
The configurable process transmitters type UPT-20, have 4-20 mA output with HART Protocol and intrinsically safe protection option. For Ex – proof options, which is the most used in the Oil & Gas sector, there is the option of the IPT-10 process transmitter. The latter also has the option of handling other programming protocols: Fieldbus, Profibus.
With Winters we have the Winsmart® Transmitters, to measure gauge pressure LY16 and differential pressure LY36. Its features are:
- High performance microprocessor
- Explosion proof for use in hazardous areas
- Temperature processor included
- 2% accuracy standard; 0.5%, 0.1%, 0.075% or 0.05% optional.
- Simple to operate single 3-push button control
- HART® or Modbus protocols available
- Low power supply
- Re-zero function
- 10:1 rangeability allowed to work in any application
- 5-year warranty