Showing posts with label Metro New York. Show all posts
Showing posts with label Metro New York. Show all posts

How to Change Loss of Signal Failure Mode on the Cashco Ranger Control Valve


This video provides step-by-step instructions on how to change the Cashco Ranger (control valve) loss of signal failure mode from air to open / fail closed to air to close/ fail open, as well as remounting and recalibrating the valve positioner.

The Cashco Ranger is one of the most popular control valves on the market. It is the most versatile, adaptable, and easily maintainable valve ever produced.

The Ranger offers over 6 different trim combinations. Trim can easily be changed in less than 5 minutes without disturbing the packing, actuator, or positioner calibration. The service area is a thread-less design, which resists corrosion or collection of chemical deposits.

A selection of 3 body materials with a broad temperature range from -325°F to +750°F makes the Ranger adaptable for use in steam, heat transfer fluids, slurries, gases, liquids, and cryogenic applications. The Ranger’s unique dual seating design provides both Class VI and backup Class IV seat leakage. And the standard patented live-loaded packing system lets you check and adjust packing without the need for specialized tools or complicated procedures.

For more information about Cashco in Metro New York, New Jersey, and Eastern Pennsylvania contact:

Miller Energy, Inc.
New York Metro and Northern NJ: 800-631-5454
Eastern PA, Southern NJ, Delaware: 888-631-5454
https://www.millerenergy.com

Refractometry in Oil Refining and the Petrochemical Industry: Sulfuric Acid Alkylation

Refractometers Used in Sulfuric Acid Alkylation

SULFURIC ACID, H2SO4
Typical end products

  • Alkylate (premium higher-octane gasoline blending stock for motor fuel and aviation gasoline).
Chemical curve: Sulfuric acid 88-100 R.I. per Conc wt.-% at Ref. Temp. of 20 ̊C

Refractometers Used in Sulfuric Acid Alkylation



Introduction

Motor fuel alkylation using sulfuric acid (H2SO4) or liquid hydrofluoric acid (HF) is one of the oldest catalytic processes used in petroleum refining. The purpose of the alkylation is to improve motor and aviation gasoline properties (higher octane) with up to 90 % lower emissions compared to conventional fuel usage.

The problem with HF is that the catalyst forms a hazardous air pollutant when released as a superheated liquid, while H2SO4 does not. Therefore nearly 90 % of all alky units built since 1990 have adopted the H2SO4 technology. 

The leading alkylation unit licensor, with a 90 % share of the market, is DuPont (Stratco®). Another licensor is EMRE (Exxon Mobile Research Engineering, formerly K.W. Kellogg).

Application

In the process, isobutane is alkylated with low molecular weight olefins (propylene, butylene and pentylene) in the presence of a strong acid catalyst to form alkylate (the premium higher-octane gasoline blending stock). The catalyst (sulfuric acid) allows the two-phase reaction to be carried out at moderate temperatures. The phases separate spontaneously, so the acid phase is vigorously mixed with the hydrocarbon phase to form higher molecular weight isoparaffinic compounds.

After the reactor, the mixture enters a separation vessel where the acid and hydrocarbon separate. The acid is then recycled back to the reactor.

Instrumentation and installation

Refractometers Used in Sulfuric Acid AlkylationThe K-Patents Process Refractometer PR-43-GP is installed after the settlers to continuously monitor in real-time the concentration of acid in the process.

The concentration of sulfuric acid is critical to achieve the complete consumption of isobutane. A highly variable concentration of isobutane in the feedstock upsets the sulfuric acid content in the process.

It is important to determine the proper quantity of acid that will be fed into the process. This is achieved by combining routine sample titration analysis with continuous acid monitoring by the K-Patents Process Refractometer. Real-time measurements reduce the need for sampling and laboratory analyses that cause delay in the implementation of any necessary adjustments to the acid flow.

Continuous monitoring removes the uncertainty involved between titration measurements. The K-Patents refractometer will indicate any gradual fluctuations in the acid flow, allowing precise control over efficient acid consumption and resulting in cost savings. It is also useful in preventing acid runaway, an unwanted situation commonly described as wild acid.

Acid runaway may happen when the acid strength drops below 85-87 % H2SO4. As a result, the reactions between olefins and isobutane turn into reactions of olefins only, producing polymers known as acid sludge, ASO or red oil.

The K-Patents refractometer is not affected by acid soluble oil (ASO). The refractometer indicates actual acid strength regardless of the amount of hydrocarbons present, which is essential when transferring acid emulsion. It is also an extremely useful tool in real-time process acid strength measurement during agitated conditions.

The initial acid concentration is typically 85-100 % and the temperature is 15 °C (59 °F). The benefits of the K-Patents refractometer’s continuous monitoring system include substantial cost savings due to reduced acid consumption, and smooth alkylate production without acid runaways.

The K-Patents Process Refractometer System for Alkylation Acid Measurement Consists of:

  1. The K-Patents Process Refractometer PR-43 for hazardous locations in Zone 2. or The K-Patents PR-43 Intrinsically Safe model for installations in hazardous locations up to Zone 0.
  2. Optional parts:
    1. Different flow cell options for easy sensor installation
    2. EXd enclosure for easy isolator and transmitter mounting
    3. Parts for a start up
    4. Spare parts supplied for two years of operation
    5. Start-up and commissioning service
  3. User specified tests and documentation.

Alloy C-276/ASTM C276 should be considered as wetted parts material when the acid piping flow velocity is at a maximum of 6 m/s (20 ft/s). Alloy 20 can be considered when acid piping flow velocity is at a maximum of 1.8 m/s (6 ft/s). However, it is the responsibility of the end-user to specify the appropriate material, ensuring that it is satisfactory for the intended operating requirements.

Non-sparking incentive (Ex nA) and intrinsic safety (Ex ia) approvals are available for hazardous area installations.

Always consult an applications expert with any process-critical instrumentation application. By doing so, you will ensure a successful, safe, and efficient deployment.

Miller Energy, Inc.
https://millerenergy.com
800-631-5454

Reprinted with permission from K-Patents.

Hazardous Areas: Division and Zone Classification System

Hazardous area
Hazards areas are associated with flammable
vapors or gases, ignitable fibers, and combustible dusts.
Hazardous areas refer to locations with a possible risk of explosion or fire due to dangerous atmosphere. The hazards can be associated with flammable vapors or gases, ignitable fibers, and combustible dusts.

Different hazardous area classifications exist in the North America and Europe. Generally, the National Electric Code (NEC) classifications govern hazardous areas in the US. While in Europe, hazardous area classification has been specified by the International Electrotechnical Commission (IEC).

Below is a description of the Division and Zone classification system.



CLASS
NATURE OF HAZARDOUS MATERIAL
CLASS I
Hazardous area due the presence of flammable vapors or gases in sufficient quantities to produce ignitable mixtures and cause an explosion.
Examples include natural gas and liquified petroleum.
CLASS II
Hazardous area due the presence of conductive or combustible dusts in sufficient quantities to produce ignitable mixtures and cause an explosion.
Examples include aluminum and magnesium powders.
CLASS III
Hazardous area due the presence of flammable fibers or other flying debris that collect around lighting fixtures, machinery, and other areas in sufficient quantities to produce ignitable mixtures and cause an explosion.
Examples include sawdust and flyings



Division groups hazardous areas based on the chances of an explosion due to the presence of flammable materials in the area.

DIVISION
LIKELIHOOD OF HAZARDOUS MATERIAL
DIVISION 1
Areas where there is a high chance of an explosion due to hazardous material that is present periodically, intermittently, or continuously under normal operation.
DIVISION 2
Areas where there is a low chance of an explosion under normal operation.


Group categorizes areas based on the type of flammable or ignitable materials in the environment. As per NEC guidelines, Groups A to D classify gasses while Groups E to G classify dust and flying debris.
GROUP
TYPE OF HAZARDOUS MATERIAL IN THE AREA
GROUP A
Acetylene.
GROUP B
Area contains flammable gas, liquid, or liquid produced vapor with any of the following characteristics:
  • Minimum Ignition Current (MIC) value equal to or less than 0.40
  • Maximum Experimental Safe Gap (MESG) value equal to or less than 0.45 mm
  • Combustible gas with more than 30 percent volume
Examples include hydrogen, ethylene oxide, acrolein, propylene oxide.

GROUP C
Area contains flammable gas, liquid, or liquid produced vapor with any of the following characteristics:
  • Minimum Ignition Current (MIC) value between 0.40 and 0.80
  • Maximum Experimental Safe Gap (MESG) value greater than 0.75 mm
Examples include carbon monoxide, hydrogen sulphide, ether, cyclopropane, morphline, acetaldehyde, isoprene, and ethylene.

GROUP D
Area contains flammable gas, liquid, or liquid produced vapor with any of the following characteristics:
  • Minimum Ignition Current (MIC) value greater than 0.80
  • Maximum Experimental Safe Gap (MESG) value greater than 0.75 mm
Examples include ammonia, gasoline, butane, benzene, hexane, ethanol, methane, methanol, natural gas, propane, naphtha, and vinyl chloride.

GROUP E
Area contains metal dusts such as magnesium, aluminum, chromium, bronze, titanium, zinc, and other combustible dusts whose abrasiveness, size, and conductivity present a hazard.

GROUP F
Area contains carbonaceous dusts such as charcoal, coal black, carbon black, coke dusts and others that present an explosion hazard.
GROUP G
Area contains combustible dusts not classified in Groups E and F.
Examples include starch, grain, flour, wood, plastic, sugar, and chemicals.


NOTE: This post serves only as a guide to acquaint the reader with hazardous area classifications in the USA. It is imperative to discuss your instrumentation, valve, or process equipment requirement with a qualified applications expert prior to installing any electrical device inside of any hazardous area.


Understanding How Magnetic Flowmeters Work and the Difference between AC and DC Excitation


The electromagnetic flowmeter, commonly known as the "magmeter", gets its name from the magnetic field generated within the float tube that produces a signal proportional to flow. This principle employs Faraday's Law of Electromagnetic Induction. Magnetic flowmeters are built so the direction of the magnetic field is perpendicular to the flow and the line between the electrodes is also perpendicular to the flow. As a conductive liquid flows through the flowtube, an electro-motive force is generated. The electrodes detect the electro-motive force. The electro-motive force is proportional to the flow velocity, flux density, and the meter inner diameter. The flux density of the magnetic field and the meters inner diameter are constant values, therefore the magnetic flow meter can calculate the flow velocity and volumetric flow from the electro-motive force.

The basic components of the magnetic flow meter body are:

  1. A lined flowtube (typically Teflon)
  2. Excitation coils
  3. Two electrodes mounted opposite of each other within the flowtube.

Current is applied to the coils in the magmeter to generate a magnetic field within the flow tube. As a conductive fluid flows through the meter, an electro-motive force is generated. This force is detected by the electrodes and the resulting value is converted to flowrate.

For more information on magnetic flowmeters, contact Miller Energy, Inc. by calling 800-631-5454 or by visiting https://millerenergy.com.

6 Benefits of Using Wireless Networking Systems in Industrial Applications

Wireless Networking Systems in Industrial ApplicationsWireless technologies offer great value over wired solutions. A reduction in cost is just one of the many benefits of switching to the wireless networking system. There are many benefits, including enhanced management of legacy systems that were previously not possible with a wired networking connection.

Here is an overview of some of the value-added benefits of adopting wireless networking in industrial plants.
  1. Reduced Installation Costs - Savings in installation costs is the key benefit of a wireless networking system. The cost of installing a wireless solution is significantly lower as compared to its wired counterpart. Installing a wireless network requires less planning. Extensive surveys are not required to route the wires to control rooms. This reduced installation cost is the main reason industrial setups should consider going wireless instead of having a wired networking system. 
  2. Improved Information Accuracy - Adopting wireless networking also results in improved accuracy of information. The wireless system is not prone to interferences. As a result, the system ensures consistent and timely transfer of information from one node to another. 
  3. Enhanced Flexibility - Enhanced flexibility is another reason for deploying wireless networking solutions in an industrial setting. Additional points can be awarded easily in an incremental manner. The wireless system can also integrate with legacy systems without any issues. 
  4. Operational Efficiencies - Migrating to wireless networking can help in improving operational efficiencies as well. Plant managers can troubleshoot and diagnose issues more easily. The system facilitates predictive maintenance by allowing the monitoring of remote assets. 
  5. Human Safety - Another critical factor that should influence the decision to migrate to wireless networking is the human safety factor. Wireless technologies allow safer operations, reducing exposure to harmful environments. For instance, a wireless system can be used in taking a reading and adjusting valves without having to go to the problematic area to take measurements. With wireless networking systems, readings can be taken more frequently that can help in early detection and reduction of possible incidents. 
  6. Efficient Information Transfer - Another advantage is that the time required to reach a device is reduced. This results in a more efficient transfer of information between network segments that are geographically separated. The industry wireless networking standards use IP addresses to allow remote access to data from field devices. 

For more information on wireless technologies in industrial settings, contact Miller Energy by visiting https://millerenergy.com or by calling 800-631-5454.

Selecting the Right Magnetic Level Indicator

Companies in the process industry need the ability to visually monitor liquid levels in vessels (boilers, storage tanks, separators, etc.). Traditionally, armored glass sight gauges have been used. However, many companies want an alternative to sight gauges to avoid problems such as breakage, leaks, or bursting at high pressures and temperatures. In addition, the visibility of the sight glass can be poor and often affected by moisture, corrosion, or oxidation.

Many companies are increasing the use of automation and desire a 4–20 mA, HART®, FOUNDATION® fieldbus, or other output for level—which is difficult to do with a sight glass. Magnetic level indicators (MLIs) do not have the shortcomings of glass sight gauges and are suitable for a wide variety of applications.

Orion Instruments, a Magnetrol company, has authored an excellent Magnetic Level Indicator selection guide.


Miller Energy, Inc.
https://millerenergy.com
In NY/NJ 800-631-5454
In Eastern PA 888-631-5454

Understanding How Flame Arresters Work


Flame Arrester
A Flame Arrester (or arrestor) is a passive devices with no moving parts, that allows hot gas to pass through, but stops a flame in order to prevent a larger fire or explosion.  Flame Arresters uses a wound metal ribbon type element that prevents the spread of flame from the exposed side of the arrester to the protected side of the arrester. The metal element's construction provides a matrix of engineered openings that are carefully calculated and sized to quench the flame by absorbing the flame's heat. As an explosion flame travels through a narrow metal space, heat is transmitted to the walls, energy is lost and only vapor gasses are able to pass through. Flame Arresters are used in many industries chemical, petrochemical, pulp and paper, refining, pharmaceutical, mining, power generation, and wastewater treatment.

Cashco Flame Arresters are specifically engineered to match the explosive mixtures Maximum Experimental Safe Gap, in order to ensure complete extinction of the flame. At the heart of each Cashco flame arrestor lies filter discs that consists of wound, smooth and channeled strips of stainless steel set at specific maximum experimental stage gaps the smaller the gaps are which the flame travels the more heat and energy is lost therefore the filters gap width and gap length are specifically engineered to match the explosive mixture in order to ensure complete extinction of the flame. 

To learn more about Cashco flame arrestors, contact Miller Energy, Inc. by calling 908-755-6700 or by visiting https://millerenergy.com.


The Yokogawa 4-Wire SENCOM™ SMART Sensor Platform

Analyzer FLXA402
Multi-Channel/Parameter Analyzer FLXA402
The SENCOM SMART Sensor Platform has been designed with a strong focus on Yokogawa's digital SMART sensors and provides greater insight and enhanced capabilities for more reliable data across the entire product lifetime.

Yokogawa's latest SMART sensor system enhances the operation, reliability, and credibility of online process analyzers, from the engineering and purchasing to modification and optimization, by using the latest sensing technologies and asset management tools.

The SENCOM SMART Sensor Platform has been designed with a strong focus on Yokogawa's digital SMART sensors and provides greater insight and enhanced capabilities for more reliable data across the entire product lifetime.

Digital SMART SENCOM™ Adapter, SA11
Digital SMART SENCOM™ Adapter, SA11
Yokogawa's latest SMART sensor system enhances the operation, reliability, and credibility of online process analyzers, from the engineering and purchasing to modification and optimization, by using the latest sensing technologies and asset management tools.

Simple Setup and Configuration

Analog sensors equipped with a Variopin connector and Yokogawa ID chip
Analog sensors
The SENCOM 4.0 Platform is designed with an intuitive menu structure, easy-to-understand configuration, alarm settings, and clear error-fixing information to help you make credible and reliable measurements of online process control.

Environmentally Friendly Design

Conventional SMART sensors include integrated electronics on top of an analog sensor, therefore the still operating electronics must be thrown away once the sensor has reachable the end of its lifetime, adding to global waste.

The SENCOM 4.0 platform includes a reusable SMART adapter, so only an analog sensor has to be removed when it reaches the end of its lifetime, thereby reducing waste and costs.

Easy and Efficient Maintenance

Optional Digital SMART SENCOM™ Expansion Junction Box, BA11
Optional Digital SMART SENCOM™
Expansion Junction Box, BA11
The Maintenance Manager is a data management system that allows technicians to forecast maintenance and calibration frequency, estimate the service life of the sensor, and estimate the life expectancy of the sensor.

Calibration data are stored within the memory chip of the SMART sensor using the SENCOM 4.0platform. Once the sensor is connected to the analyzer, it is possible to download or upload the latest calibration data to the FLXA402 analyzer, thus avoiding the need for field calibration.

For more information, visit this page on the Miller Energy website.

Miller Energy, Inc.
800-631-5454

Level Instruments for Tank Overfill Protection

Tank overfill incidents in recent years have resulted in loss of life and billions of dollars in damages to petroleum facilities worldwide. One of the worst incidents - the overflow of a gasoline storage tank at Buncefield Oil Depot (U.K.) - has been traced to the failure of level control to maintain containment of the flammable liquid. More common are minor spills that cause significant environmental impact and result in millions of dollars in clean-up fees and environmental agency fines.

In the wake of this incident, the American Petroleum Institute’s (API) Recommended Practice (RP) 2350, the most widely accepted guideline for overfill protection of petroleum storage tanks, has been revised. The fourth edition was published in May 2012 and combined the prescriptive standards of RP 2350 with the functional safety standards of Safety Instrumented Systems (SIS) as described in IEC 61511.

Vital to these new requirements is the application of level instrumentation as one part of a comprehensive Overfill Prevention Process (OPP).

Magnetrol, a world-leader in the design, manufacturer and application of level and flow instrumentation, has written an application document titled "Level Instruments for Tank Overfill Protection". Get your copy here.

The Yokogawa YS1700 Single Loop Controller Replaces Obsolete Moore/Siemens 353

Yokogawa YS1700

Now that entire Moore/Siemens 350 family is obsolete, are you considering upgrading to a DCS? 


Are you concerned about the cost and time for a new installation, application development and personnel training?

Is it possible that the new equipment vendor may again leave you stranded with their equipment as their core business is not industrial automation and control?

We have a better solution for you: Yokogawa and its YS1700 PID loop controller. Yokogawa has been providing industrial solutions, as their primary business, for over a century and their YS1700 will keep you off of eBay looking for spare 353 parts.

The Magnetrol ECHOTEL 962 Dual Ultrasonic Level Control


The Magnetrol ECHOTEL Model 962 is a dual point switch that can be used as a level controller, or to control pumps in an auto fill or auto empty mode. The tip sensitive lower gap performs well in aerated or foamy liquids, and can measure to within 1.4" of the vessel bottom. The rigidity of the unique flow-through upper gap allows separations of up to 125" (318 cm) between the upper and lower transducer gaps.

The Magnetrol ECHOTEL 962 offers the ultimate solution to reliable dual point liquid level measurement. This advanced switch uses pulsed signal technology for superior performance in difficult process conditions, and to provide excellent immunity from sources of electrical noise interference. Extensive self-testing of the electronics and transducer make this advanced switch suitable for use in Safety Integrity Level (SIL) 2 loops.

The ECHOTEL Model 962 is equipped with advanced diagnostics that continuously check the sensor and electronics. The diagnostics also alarm for electrical noise interference from external sources.

Ultrasonic contact switches use a pair of piezoelectric crystals that are encapsulated in epoxy at the tip of the transducer for level measurement. The crystals are made of a ceramic material that vibrates at a given frequency when subjected to an applied voltage. The transmit crystal converts the applied voltage from the electronics into an ultrasonic signal. When liquid is present in the gap, the receive crystal senses the ultrasonic signal from the transmit crystal and converts it back to an electrical signal.

Miller Energy, Inc.
https://millerenergy.com
800-631-5454

ASCO Express Product Catalog

The ASCO Express program features a range of flow control products and accessories available for shipment the same day you order them. The products listed in this catalog provide the performance required for a variety of system and process applications including boiler, air handling, process control, and water and steam control. The control voltages available for each product are the primary voltages used in industrial and commercial applications today.

908-755-6700

Water and Wastewater Treatment Applications for the Magnetrol R82 Pulse Burst Radar Transmitters


The Magnetrol R82 Pulse Burst Radar transmitter performs across a wide range of applications. The R82 is designed to provide radar reliable process measurement in challenging, vapor saturated environments, at the cost of what you pay for an ultrasonic device. For water treatment, the Magnetrol R82 Pulse Burst Radar transmitter provides continuous level measurement at the lift station and coagulant feed tanks, in settling tanks during clarification, in polymer, filter, and lime slurry tanks during filtration, and for open atmosphere water reservoirs where the control technology must withstand punishing weather conditions.  In wastewater facilities, the R82 radar can control level at the lift station pump, open channel flow and screening system, monitor feed tanks containing chemical coagulants oxidants and phosphorous precipitation, measure splitter box in clarifier levels, control corrosion inhibitors, manage pH adjustment, mixed liquor and secondary clarifier levels, as well as activated sludge and digester level control.

Miller Energy, Inc.
https://millerenergy.com

Temperature Switches

temperature switch
Temperature switch
(United Electric Controls)
A temperature switch detects the temperature of some substance. Temperature switches often use bimetallic strips as the temperature-sensing element, the motion of which actuates one or more switch contacts. An alternative design uses a metal bulb filled with a fluid that expands with temperature, causing the switch mechanism to actuate based on the pressure this fluid exerts against a diaphragm or bellows. This latter temperature switch design is really a pressure switch, whose pressure is a direct function of process temperature by virtue of the physics of the entrapped fluid inside the sensing bulb.

The “normal” status of a switch is the resting condition of no stimulation. A temperature switch will be in its “normal” status when it senses minimum temperature (i.e. cold, in some cases a condition colder than ambient). For a temperature switch, “normal” status is any sensed temperature below the trip threshold of the switch.

switch contacts

Like all other process switches, temperature switches exhibit a certain amount of deadband in their switching action. A temperature switch that trips at 300 F rising, for example, will not reset at 300 F falling. That switch would more likely reset at some lower temperature such as 295 F. With mechanical switch designs, some amount of deadband is inevitable due to friction inside the mechanism. However, process switch deadband is actually a useful characteristic as it helps avoid repeated “nuisance” alarms from happening.

To understand this concept, it is helpful to imagine a scenario where the process variable is at or very near the trip point. For our hypothetical temperature switch with a trip point of 300 F (rising), imagine a situation where the process temperature is precisely 300.0 F. Any further rise in temperature will of course trip the switch (sounding an alarm). With no deadband, however, the switch will immediately re-set when the temperature falls back down to 300.0 F. This means the switch may possibly “cycle” back and forth between its trip and reset states with just a minute change in process temperature (300.0 F to 300.1 F and back again). If the temperature switch is activating an alarm every time it trips, it will create a series of alarm events prompting operators to repeatedly acknowledge the alarm. This is a nuisance to operations personnel, as it distracts them from addressing what they already realize is a process problem. It is better for the switch to trip at 300.0 F rising and remain in that tripped state until the temperature falls down to some degree substantially below the trip point. This way, the operators only receive one alarm event rather than multiple alarm events for each process temperature excursion.

Some mechanical temperature switches come equipped with a separate adjustment for deadband (also called differential). Setting this deadband adjustment in a mechanical temperature switch requires the technician to repeatedly subject the sensing element to a rising and falling temperature, to check that the switch trips at the proper setting and resets at the proper setting. This is analogous to cycling the process variable back and forth when adjusting the “zero” and “span” settings of an analog transmitter: checking to see that the transmitter repeatedly outputs a 0% signal at the lower range value (LRV) and a 100% signal at the upper range value (URV). 

For discrete temperature-sensing applications demanding high accuracy and repeatability, electronic temperature switch circuits using thermocouples, RTDs, or thermistors may be used instead of a mechanical (bi-metallic or filled bulb) sensing element. The operation and configuration of discrete electronic temperature switches is very similar to that of continuous electronic temperature transmitters.

An example of an electronic temperature switch module is the United Electric One Series shown below:

UE Series One Electronic Temperature Switch
UE Series One Electronic Temperature Switch

With electronic temperature switches, the adjustment of deadband (differential) is both precise and flexible. Unlike mechanical switches where deadband is primarily a function of friction, and therefore liable to change over time as the device wears, electronic switching circuits may be precisely set for any trip and reset points along its measurement range, remaining very stable over time.

For more information about temperature switches, contact Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700.


Text adapted from "Lessons In Industrial Instrumentation" by Tony R. Kuphaldt – under the terms and conditions of the Creative Commons Attribution 4.0 International Public License.

How Do Pilot Operated Tank Relief Valves Work?

Storage tanks become pressurized when liquid is pumped in and compresses the existing tank vapor. Tanks also become pressurized due to increasing ambient temperatures, which cause the tank vapor to expand. To mitigate damage from these expanding tank vapors, pressure relief valves are installed on tanks to prevent structural damage resulting from over-pressure.

Here is an excellent animation, courtesy of Cashco, that shows how a pilot operated relief vent protects a storage tank from over pressurizing during a pump-in situation or during thermal heating conditions.


For more information on tank relief valves, contact Miller Energy at www.millerenergy.com or by calling 908-755-6700.

Common Instrumentation Requirements for Industrial Boilers

Instrumentation Used on Industrial Boilers
Typical boiler instrumentation layout.
(courtesy of Yokogawa)
Boilers are used in a broad range of industries such as electric power, pharmaceuticals, chemicals, ceramics, and paper and pulp. Amid the rising energy costs, tightening environmental regulations, and increasing awareness of safety as of late, the needs for high efficiency operation, low emission operation, and safe and stable operation of boilers are growing.

In order to ensure the air and fuel are combusted at an optimal ratio, the waste of fuel is eliminated, and the exhaust gas is cleaned, real-time monitoring of the oxygen concentration of combustion gases is required. Equipped with an oxygen sensor unit with a longer life span, the Zirconia Oxygen Analyzer ZR series are capable of measuring an oxygen concentration with high reliability. The Stack Gas Analyzer monitors exhaust gas components such as NOX, SO2, and CO2 in order to ensure low emission operation.

A single-loop controller can be used to properly distribute control functionality. Offering the advantages of flexibility of building distributed control systems, simple maintenance, compatibility with conventional systems, and the like, the YS1000 Series of Single-loop Controllers are ideal for safe and stable operation at low costs.

In order to ensure highly efficient and safely operated boilers, it is also indispensable to accurately monitor the drum level and steam flow rate. The EJA and EJX Series of Differential Pressure Transmitters are capable of measuring the drum level with high stability even in actual applications at high temperatures and high pressures. The DY Series MV TYPE of Vortex Flowmeters with a simple construction employ a built-in sensor to measure the steam mass flow with high reliability.

Yokogawa offers a wide variety of sensors and controllers that are used to monitor and operate boilers, and contributes to increasing the efficiency and environmental performance of boilers, as well as ensuring their safe and stable operation.

Recommended Products for Boiler Applications


  • Drum Level Measurement - EJA/EJX transmitters
  • Combustion Control - The YS1000 Dual CPU Loop Controller
  • Steam Flow Measurement - Digital YEWFLO MV Type
  • Combustion Monitoring - Zirconia Oxygen Analyzers and AV550G Multi Oxygen Sensor Converter

For more information in Eastern Pennsylvania, New Jersey, Metro New York or Delaware contact:
Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700 in New Jersey, or 610-363-6200 in Pennsylvania.

Detailed Look at the Yokogawa YS100 Series as a Replacement for the Obsolete Siemens 353

This video is a thorough presentation detailing why and how the Yokogawa YS1000 Series is the best replacement for the obsolete Siemens/Moore 353 controller. It is composed of a series of presentation slides - hit the pause button to focus on any single slide.

New Jersey: 908-755-6700 
Pennsylvania: 610-363-6200

An Excellent Replacement for the Discontinued Siemens 353 SLC

Siemens 353 replacement
The Yokogawa YS1700 is a great replacement to the
discontinued Siemens 353 SLC controller.

The discontinuation of the Siemens 353 SLC controller is a concern to many users of this popular controller. With few alternatives, customers are joking that they'll have to turn to eBay for spare parts. There's a much better solution though. The Yokogawa YS1700 PID loop controller, a drop-in replacement for the Siemens 353 SLC.

The Yokogawa YS1000 Series is the ideal choice for many control applications offering extreme reliability and sophisticated control. This product family has bright, easy-to-read displays, multiple I/O points, and powerful loop tuning. For critical applications, the YS1700 employs dual CPUs for maximum reliability and hard-manual control for added protection. The YS1700’s powerful function block programming allows for custom strategies to control many demanding processes such as boilers and steam generators, PH control, dosing control, and many other demanding plant processes.

To learn more about replacing the Siemens 353 with a Yokogawa YS1700, visit this page or go directly to this link https://millerenergy.com/Siemens-353-Replacement.

How to Select a Pressure Switch

UEC One Series Switch Transmitter Hybrid
UEC One Series Switch Transmitter Hybrid
Reprinted with permission from United Electric Controls

Pressure switches are widely used by many industries and within many applications. The basic function of a pressure switch is to detect a pressure change and convert it into an electrical signal function – typically on/off or off/on. Pressure switches may be of electro-mechanical or electronic/solid-state design (see our ONE Series); and while each may have its advantages, arriving at the correct pressure switch for your application is the same.

Set Point & Deadband


Application set point (sp) is the desired value reached at rising or falling pressure at which the micro-switch changes electrical states. Depending upon the pressure switch function, the micro-switch could be wired to open (turn something OFF)  or close (turn something ON) when set point is achieved, thereby triggering an event such as an alarm, equipment shutdown, or powering up secondary equipment. Ideally, the set point should fall into the mid 50% of the pressure switch range for best performance including repeatability and long life. On an electro-mechanical pressure switch, set point may be adjusted internally or externally either through blind adjustment or reference dial. An electronic pressure switch would have internal or external adjustment via a key pad and digital display or a handheld programmer.
Deadband graph

Deadband (DB) is the on-off differential required to reset the micro-switch. This value may be fixed or adjustable with an electro-mechanical switch and may be up to 100% adjustable on an electronic switch.

Deadband may be an important factor to consider depending upon the application requirements.

System Pressure


Knowing your normal and maximum system pressures will help in selecting a pressure switch with appropriate minimum and maximum operating parameters. Once your set point is established, other factors to consider are vacuum and/or surge pressure that could affect switch operation. This would involve maximum working pressure, over range pressure, and proof pressure specifications of a pressure switch. The relationship between set point and system pressure has a direct effect on switch performance and life.

Electrical Considerations


UEC 100 Series Pressure Switch
UEC 100 Series Pressure Switch
Micro-switches are available in a variety of configurations. The most common for electro-mechanical pressure switches is 15A, 480VAC SPDT (single pole, double throw). The advantage of a SPDT micro-switch is that it offers wiring flexibility to either open or close on pressure change. Other micro-switches available include 1A with gold contacts, useful when working with a PLC, or at the upper end, 30A when switching certain high voltage heaters or motors. Adjustable micro-switches help with deadband adjustment. A DPDT (double pole, double throw) micro-switch would provide two simultaneous functions off of one micro-switch. If a low-high limit alarm and shutdown were required, there are pressure switches that include two SPDT micro-switches that are independently settable.

An electronic pressure switch would use solid-state relays to change states. Like an electro-mechanical switch, the electronic switch can be programmed to open or close on rising or falling pressure. There are different capacities for switching voltage and current depending upon the application requirements.

Process Media and Wetted Parts


The pressure connection and sensor are known as wetted parts since they come into direct contact with the process media. Sensor material is either elastomer (i.e. Buna-N, Teflon®) or metallic (i.e. Brass, Stainless Steel) with metallic or composite pressure connections. The process media must be compatible with the wetted parts material. Process media temperature should also be considered as each of the different wetted materials would have differing operating properties.

Pressure Switch Mounting


If the unit is to be installed directly onto the process, there are many methods of installation.
Typically a 1/8”, 1/4”, or 1/2” NPT (national pipe thread taper) connection is used with a mating
fitting to secure the pressure switch to the process. There are also straight threaded (SAE, BSPT)
connections, flush mount connections, and sanitary connections. The pressure switch may be
mounted directly in the process line using the threaded connection, a manifold, or flange; or the
enclosure could be bolted to a mounting plate or other plane to secure it. If heavy vibration is
present, you may choose to use a remote diaphragm seal with the pressure switch. The diaphragm
seal mates with the process connection while the pressure switch enclosure is mounted securely
away from the vibration. 

Process Environment


It is important to know what type of environment the pressure switch would be installed in – hazardous or ordinary location; indoors or outdoors; exposed to salt air; inside a control panel; in high ambient temperature. These are just some of the factors to consider so the right enclosure type is chosen. Enclosure types come in many shapes, sizes, and materials. They also conform to various industry and third-party approval standards. Electronic switches can be used to replace electro-mechanical switches when SIL is needed for safety applications.  There are also electro-mechanical pressure switches without enclosures; typically used in OEM, non-hazardous locations where the environment is benign.

With careful consideration of all the factors listed above, choosing a pressure switch is a snap. If you are at all unsure, please contact your local United Electric Distributor or visit the UE Product Selector to find your pressure switch.