Saturday, July 16, 2016

Examining the User Interface of the SensAlert ASI Gas Detector

The Sensidyne SensAlert ASI provides enhanced protection and dependability for critical safety applications where personnel, processes, and facilities are at risk. The third party certified SIL-2 SensAlert ASI offers dependability and versatility while remaining the easiest to install, commission, operate, and maintain.

The video below demonstrates the setting menu and the operator interface.

The product is third-party certified to IEC61508 Level 2 (SIL-2) for both hardware and software with certification to global hazardous area and performance standards. The Test-on-Demand feature with on-board gas generator provides remote functionality checks with generated gas while Predictive Sensor End-of-Life Indication provides advanced warning of impending sensor failure.

SensAlert ASI is a universal instrument platform for toxic & combustible gas detection and oxygen monitoring. Intrinsically safe or explosion proof installation configurations with options for remote sensors and gassing, duct mount, and sample-draw maximize application versatility. Intrinsically safe or explosion proof installation configurations for remote sensors and gassing, duct mount, and sample-draw maximize application versatility. The sensor head accepts all Plus Series sensor technologies – infrared, catalytic bead, and electro-chemical. Assignable and configurable relays together with communication options provide broad flexibility. The SensAlert ASI I.S. sensor head can be remote mounted up to 100 feet (30m) from the transmitter providing a useful option to position the transmitter in a personnel-accessible location while positioning the sensor closer to potential hazards.

Thursday, June 30, 2016

Food Processing: Belt Scales Improve Tomato Processor Efficiency and Productivity

Belt Scales Improve Tomato Processor Efficiency
Belt Scales Improve
Tomato Processing
The following post is a case history on using alternative technology to improve large scale food preparation process.  You'll read about how belt scales outperformed legacy equipment for a tomato peeling process and increasing yield.


A tomato processor located on the Paciļ¬c coast uses the latest technologies in peeling, dicing, and packaging tomatoes. They were preparing to replace some of their older weigh feeders because of declining performance. One of their main concerns with installing new weigh feeders was the cost of moving the existing conveying systems in order to accommodate new weigh feeders.

See the document below for the full case history:

Wednesday, June 22, 2016

2 Wire, 3 Wire, and 4 Wire RTD Sensor Connections

Industrial temperature transmitters
Industrial temperature
transmitters (courtesy of
Industrial temperature transmitters are devices that measure the temperature of a process and provide a measurable output over some desired temperature range. Industrial temperature transmitters primarily use either of two popular temperature sensors - the thermocouple or the RTD (resistance temperature detector). The RTD changes resistance as process temperature changes, while a thermocouple provides a changing micro-voltage with process temperature change. RTDs are inherently more accurate, but require excitation voltage. There are three style RTD's - 2-wire, 3-wire, and 4-wire.

Proper connections for all three types of RTD sensor to a user- configurable transmitter are shown in the following illustrations:

proper wiring of RTDs
Proper wiring of RTDs
It is critically important to note that the common connections shown by the symbols for 3- and 4-wire RTD sensors represent junction points at the sensor; not terminals jumpered by the technician at the time of installation, and not internal jumpers inside the transmitter. The whole purpose of having 3-wire and 4-wire RTD circuits is to eliminate errors due to voltage drop along the current-carrying wires, and this can only be realized if the “sensing” wire(s) extend out to the RTD itself and connect there. If the transmitter’s sensing terminal(s) are only jumpered to a current- carrying terminal, the transmitter will sense voltage dropped by the RTD plus voltage dropped by the current-carrying wire(s), leading to falsely high temperature indications.

Click here for more information on industrial RTDs and temperature transmitters.

For more information about any temperature measuring application, contact:
Ives Equipment
(877) 768-1600

Some of above content taken from Lessons In Industrial Instrumentation by Tony R. Kuphaldt – under the terms and conditions of the Creative Commons Attribution 4.0 International Public License.

Wednesday, June 15, 2016

Combustion Analyzer Adds Higher Level of Safety by Measuring O2, Combustibles, and Methane

WDG-VThe reliable identification of low combustion oxygen in a fired heater or boiler has always been critical to the effectiveness of the Burner Management System for proper control and safety.

Low emission burners and aggressive firing control points to achieve increased efficiency and emission reductions have driven the industry to tighter control measures. But tighter control measures also hold a greater potential for combustion events. Reducing the risk of a combustion event has become a priority and has led to the implementation of Safety Instrumented Systems (SIS). This additional layer of safety is added to the Basic Process Control System.

The WDG-V has been designed to provide an additional layer of safety with the measurement of excess O2, Combustibles and Methane and by using these measurements to ensure the safe operation of the Burner Management System.

WDG analyzers are based on a zirconium oxide cell that provides a reliable and cost-effective solution for measuring excess oxygen in flue gas as well as CO and methane levels. Information from the Gas Analyzer allows operators to obtain the highest fuel efficiency, while lowering emissions for NOx, CO and CO2. The zirconium oxide cell responds to the difference between the concentration of oxygen in the flue gas versus an air reference. To assure complete combustion, the flue gas should contain several percent oxygen. The optimum excess oxygen concentration is dependent on the fuel type (natural gas, hydrocarbon liquids and coal).

Tuesday, May 31, 2016

Solenoid Valve Operating Principle

solenoid magnetic field
Solenoid magnetic field
A solenoid is an electric output device that converts electrical energy into a linear mechanical force.

At its most basic level a solenoid is an electromagnetic coil that uses magnetism produced by the flow of current to physically move the armature of a solenoid. The armature that is movable can be a rod or a metallic arm. One of the most common uses of solenoids are as the operators of valves.

A plunger solenoid contains a movable iron rod that is inserted into a coiled cylinder. The rod is connected to a plate with two contacts. With the aid of a spring the contacts are normally open. When an electrical current passes through the coil, it generates a magnetic field that attracts the rod into the coil chamber. The movement of rod will move the contacts into a closed position. When the current is turned off the magnetic force is removed and the tension in the spring forces the rod back out to its original resting position. This back-and-forth motion of the rod to control a circuit is used to operate a variety of mechanical devices such as valve seats and pneumatic poppets.

solenoid valve
Solenoid valve components
A solenoid valve is a combination of two basic functional units:
  • The solenoid (electromagnet) described above.
  • A valve body containing one or more orifices.
ASCO solenoid valve
ASCO Redhat Solenoid Valve
Flow through an orifice is controlled by the movement of the core when the solenoid is energized or de-energized. The core is enclosed in a sealed tube, providing a compact, leak tight assembly.

This video provides a very basic visual understanding of the solenoid operating principle and how the mechanism works. From this video it is easy to understand how the linear movement created by the solenoid can be transformed into the movement necessary to open and close solenoid valves.

For more information about solenoid valves, contact:
Ives Equipment