Back to Basics {Part 1}: The Fundamentals of 4-20 mA Current Loops (Click Here for Spanish Version)
In the world of process control, there are a myriad of different types of process inputs. Thermocouples and RTDs provide direct temperature reading while digital signals such as Modbus® provide exacting control... Read More
Back to Basics {Part 2}: The Fundamentals of Loop-Powered Devices
Recalling from the previous part of this series, all 4-20 mA current loops require a power supply in order to operate. A lot of loop setups will utilize an external power supply in order to power the devices which are attached to... Read More
Back to Basics {Part 3}: Loop vs Line Power
The previous article in this series discussed loop-powered, or two-wire, devices. These instruments utilize the power supplied to the current loop to power themselves. A two-wire connection may not always be the most optimal power solution... Read More
Why a 0 mA Signal is Not Practical
For decades, process instrumentation has largely relied on 4-20 mA signals to transmit process data easily and reliably. Moreover, it is the signal of choice in the process control industry for many reasons. One in particular is the fact that current does not degrade... Read More
De Regreso a lo Básico: Los Fudamentos de los Lazos de Corriente de 4-20 mA (Click here for English version)
En el mundo del control de procesos, se emplean distintos tipos de señales. Termopares y RTDs proveen la lectura directa de la temperatura, mientras que las señales digitales como Modbus® proporcionan un control preciso de los variables de proceso y su visualización... Lee mas
Go Wireless Without Breaking the Bank, or Your Systems
Running physical wires between devices can be costly and time consuming, especially when there is a need to run them through conduit or dig trenches. Facilities that have been in operation for a long time may have gone through many iterations of process control equipment, leaving behind a rat's nest of old wires... Read More
Loop-Powered Indicators with Advanced Control Features
The use of loop-powered instruments in process control applications has often meant sacrificing features due to voltage drop limitations on the signal loop. While two-wire devices are cost-effective and easy-to-use, they normally lack advanced display and control capabilities... Read More
Four Tips for Wireless Installations
PDW wireless devices have been designed with ease-of-use in mind, with intuitive programming through either the front buttons or PDW Manager programming software. However, wireless communications, no matter the device, can be negatively affected by certain factors... Read More
Level Measurement Technologies In The Process Control Industry
Few things are as ubiquitous in the process control industry as the need to measure the level of a process material in a container. Whether that material is water, waste water, petroleum, sugar, or any other form of liquid or solid, level measurement accuracy can be a determining factor in both profit margins and safety... Read More
How to Measure Flow Rate with Level Sensors
Level sensors are capable of measuring more than just level. Flow rate measurement in an open channel, such as a stream, irrigation canal, or unpressurized sewerage pipe, can be accomplished... Read More
Be ready for the Summer Sun with Sunlight Readable Displays
With the summer months ahead, many are looking forward to bright and sunny days. However, to those who work with process instrumentation outdoors, the sun may seem a never-ending source of frustration... Read More
Reducing Signal Noise in Practice
Signal noise in an industrial environment has the ability to cause havoc with process control systems. This electrical noise can inject itself onto analog or digital signals and fool control equipment.... Read More
Level Monitoring & Pump Control with the ProVu PD6000
Level measurement and pump control go hand-in-hand, whether it is making sure that your tanks stay full or that they don’t overflow. Traditionally, however, these two processes required separate devices... Read More
Alarming Possibilities: ISA Alarm Sequencing In A Nutshell
Alarms are a necessary part of the process control industry. Unintended faults in automation equipment are inevitable and must be communicated to operators clearly... Read More
Boosting Efficiency in a Natural Gas Flow Application
The end user is a natural gas transportation and storage service provider in the USA with a natural gas storage well flow application. The customer's primary concern when considering a system upgrade was to track flow rate and display the rate locally... Read More
The Current Quandary: Ground Loops & Non-Isolated Commons
Any installer of industrial process control equipment will tell you that ground loops are one of the most frustrating signal connection errors to diagnose and repair. The steps required in order to troubleshoot them... Read More
Hazardous Area Classifications: What You Need to Know
During the evening of February 7th, 2008, a series of explosions at the Imperial Sugar manufacturing facility in Port Wentworth, Georgia, just outside of Savannah, resulted in the deaths of fourteen workers... Read More
Best Planning Practices for Level Solutions
While level applications can be found in countless industries and applications, there are certain key elements that should be considered as part of any level control solution. Read More
Unlock the Potential of Your Modbus® Transmitters
Learn what Modbus communications can do to improve your local and remote displays when combining your Modbus transmitters with a Modbus scanner. Read More
(As seen in IPP&T, Sept ’13, 44; source)
An Introduction to Modbus Communications
This article will discuss what Modbus communications is, some popular ways to use it, and explain some of the terms often associated with using it. Read More
When is a 4-20 mA Output Needed on My Panel Meter?
Most digital panel meters, controllers, and indicators have the option of a 4-20 mA output. While a very popular feature, it is worth considering whether this output is really needed for your application. Read More
Five Considerations for Selecting a Remote Level Display
Level is one of the most commonly measured process values in a wide range of applications and industries. Available level transmitters range from mechanical floats and contact probes ...Read More
ProVu Series Safety Interlock Feature
A common application for Precision Digital's PROVU series is for monitoring & alarming. In these applications, the meter is not used as a primary controller, but a safety device. As such... Read More