Glossary

ACCURACY (REPEATABILITY) — Accuracy is the maximum operational set point deviation of a single sensor (a pressure, temperature, or flow switch) under one given set of environmental and operational conditions. CCS repeatability on Industrial factory set pressure switches is within +-/ 1% of the factory set point. ACTUATION AND DEACTUATION POINT — The actuation point (sometimes called the set point) is the exact point at which the electrical circuit controlled by the switching element is opened (or closed) on increasing pressure or temperature. The deactuation point is the opposite, or the point at which the electrical circuit is closed (or opened) on decreasing pressure or temperature. ADJUSTABLE RANGE — The total range within which the actuation point (set point) of a sensor may be adjusted. AMBIENT TEMPERATURE RANGE — The maximum and minimum temperature that will surround the sensor during use and/or test ANSI (American National Standards Institute) — A federation of trade associations, professional and scientific societies, and individual company members. ANSI approves and serves as a clearinghouse for voluntary, nongovernmental American national standards. API (American Petroleum Institute) — The national trade association that provides information in the form of standards, bulletins, and recommended practices for the petroleum industry. ATEX — The Directive on Equipment and Protective Systems Intended for use in Potentially Explosive Atmospheres’ (94/9/EC) entered into force on 1 March 1996. The Directive is commonly referred to as the ‘ATEX’ Directive (‘ATmospheres EXplosibles’), but may also be called the ATEX Equipment Directive or ATEX 95. BASEEFA (British Approvals Service for Electrical Equipment in Flammable Atmospheres) — (2001) Ltd. (British Approvals Service for Electrical Equipment in Flammable Atmospheres) is the British national testing and certification authority for electrical equipment used in hazardous locations other than mines. Baseefa is a leading internationally recognized certification body for explosion protected equipment, delivering both IECEx and ATEX certification to customers around the globe. Depending on the category of equipment involved, manufacturers are also required to install a quality system that ensures that a product that has been type examined will be faithfully replicated. CHARGE — The fluid with which the temperature sensing probe is filled. CRN: (Canadian Registration Services) — Statutory Declaration, Registration of Fitting (Technical Standards and Safety Act, 2000, and Regulations for Boilers and Pressure Vessels and CSA Standard B51) CRITICAL SET POINT — The critical set point is the set point of the unit which is held to the closest tolerance. It can be either the actuation (increasing) or deactuation (decreasing) point. CSA (Canadian Standards Association) — A nonprofit voluntary association engaged in standards development and certification activities. A CSA certified electrical product conforms to applicable requirements of the Canadian Electrical Code. Representative prototypes are tested prior to certification and CSA maintains a production surveillance program to ensure continuing conformity. DOUBLE BREAK SWITCHING ELEMENT — A double break switching element has two isolated circuits; one normally open and one normally closed, the four terminals facilitate wiring. DEAD BAND (DIFFERENTIAL, ACTUATION VALUE) — The deadband of a pressure switch is the difference between the actuation point and the deactuation point. For instance, if a pressure switch reaches its actuation point and closes the snap action switch at 100 psi, it is in an actuated condition. If the pressure then drops and the switch deactuates (returns to its normal condition) at 90 psi, it is said to have a dead band of 10 psi. NOTE: CCS dead bands are within +/- 50% of the published value. DOUBLE POLE DOUBLE THROW (DPDT) SWITCHING ELEMENT — A DPDT switching element has six electrical terminals. In simple terms, it is two SPDT switching elements operating simultaneously at the same settings. This type of pressure switch can handle two independent circuits without using a relay. DUAL SEAL — The imminent Canadian national code adoption of NEC 2009 required process instrumentation such as flow, level and pressure gauges, meters and switches, to certify their devices to the ANSI/ ISA 12.27.01 standard. Supplying a device with a nameplate labeled “Dual Seal” or “Single Seal” meets the NEC 2009 code, and permits an end-user installer to eliminate a costly secondary seal. DUAL SETTING — A dual setting pressure sensor has two independently adjustable electrical switches that are actuated by a shared pressure source. Equivalent to two field adjustable pressure switches in one package. FACTORY SET — Switch which can be set only at the factory to customer’s requirements. FIELD ADJUSTABLE — A pressure switch design that provides for adjustment of set points in the field. FIELD SET — A pressure switch design that provides for field adjustment of set points. Adjustment is accomplished by turning an adjustment screw located inside of pressure port prior to installation. After unit is installed, set points can be adjusted by removing pressure fittings to access adjustment screw. FIRE RESISTANT — A pressure sensor that is designed with a high melting point barrier (steel) that will prevent full flow of sensed flammable fluid from feeding an externally caused fire. GOLD CONTACTS — Gold contact switching elements are characterized by high corrosion resistance and high reliability in switching low voltage and amperage circuits. They are recommended for intrinsically safe and computer interface circuits. GOST: (Russian: ГОСТ) — Refers to a set of technical standards maintained by the Euro-Asian Council for Standardization, Metrology and Certification (EASC), a regional standards organization operating under the auspices of the Commonwealth of Independent States (CIS). These are GOST-R, GOST-B, GOST-U and GOST-K certification trademarks demonstrating product compliance to Russia, Belarus, Ukraine, and Kazakhstan. HERMETIC SEAL — A method of sealing the electrical switching element in a sensor so that it is unaffected by all ambient external corrosive agents and explosive gases. Sealing must be accomplished by soldering, brazing, welding, and glass to metal fusion. IECEx — International Electrotechnical Commission System for Certification to Standards relating to equipment for use in explosive atmospheres (IECEx System). IECEx Certified Service Facilities Scheme Assesses and certifies that organizations and workshops that provide repair and overhaul services to the Ex industry do so respecting the strict requirement of IEC International Standard 60079-19. LIMP DIAPHRAGM — An elastomer or plastic diaphragm which is used in a pressure sensor. This type of diaphragm conforms to the shape of the sensing pressure plate and has no rigid structure itself. CCS uses polyimide, stainless steel or viton/dacron limp diaphragms. NACE (National Association of Corrosion Engineers) — Nonprofit technical association that develops and maintains standards that deal exclusively with protection and performance of materials in corrosive environments. The membership represents a cross-section of industry concerned with corrosion prevention and control. NEC (National Electrical Code) — The American national standard that contains provisions considered necessary for safeguarding persons and property from hazards arising from the use of electricity. Generally, the code covers electric conductors and equipment installed within or on public and private buildings or other structures. NEMA (National Electrical Manufacturers Association) — A voluntary organization that adopts standards for electrical equipment. NEMA standards are designed to eliminate misunderstandings between the manufacturer and the purchaser and to assist the purchaser in selecting and obtaining the proper product for a particular need. NFPA (National Fire Protection Association) — An organization that promotes the science and improves methods of fire protection. NFPA codes, standards, and recommended practices are intended to prescribe reasonable measures for minimizing losses of life and property by fire. NFPA sponsors the National Electrical Code under auspices of the American National Standards Institute. NFPA (National Fluid Power Association) — A nonprofit national trade association that coordinates and develops voluntary standards for manufacturers of hydraulic and pneumatic components and systems. NORMALLY CLOSED SWITCHING ELEMENT — Is one in which the terminals are wired so that current can flow through the switching element until the plunger pin is actuated to open the circuit. OPERATING TEMPERATURE — The temperature rating of the device considering both media and ambient temperature extremes. Factors that affect this rating include distance between media and wetted parts as well as installation methods. POLYIMIDE — A polymeric film possessing a unique combination of physical and mechanical properties which include long life, excellent deformation/set resistance, high resistance to temperature extremes, good tensile strength, and outstanding resistance to organic compounds. Polyimide is not recommended for water service above 140 °F (60 °C). PRESET — A factory set pressure switch available from stock, set to a predetermined set point. PRESSURE, ABSOLUTE — The difference between zero pressure (a perfect vacuum) and some known pressure. It may be arrived at by adding barometric pressure to gage pressure. PRESSURE, AMBIENT — The pressure (usually, but not necessarily atmospheric) surrounding a pressure sensor. PRESSURE, ATMOSPHERIC — The actual weight per unit area of the earth’s atmosphere at a given locale and altitude. Atmospheric pressure at sea level is approximately 14.7 psi or 30 inches of mercury or 408 inches of water. PRESSURE, DIFFERENTIAL — The difference between a reference pressure and a variable pressure. PRESSURE, GAGE — Gage pressure uses atmospheric pressure as a reference, and therefore will vary according to the barometric reading. PRESSURE, PROOF — Proof pressure (normally 1.5 times system pressure) is the maximum pressure which may be applied to any pressure sensor without causing permanent damage. PRESSURE, SYSTEM — The nominal pressure level that a system will operate at including work load. PRESSURE SENSING ELEMENT — The portion of the pressure switch that is in contact with and moves as a result of a change in pressure / force. The most common type of sensing elements are diaphragms, accordion bourdon tubes and pistons. PRESSURE SENSOR – A pressure sensor is any device that measures pressure and converts it to an electrical signal. It’s an all-encompassing term that includes pressure transducers, transmitters, and the sensing devices within them. All transducers and transmitters are sensors, but not all sensors are transducers or transmitters. PRESSURE SWITCH — A pressure switch is an electrical mechanical device that converts pressure into motion to operate an electrical switching element. PRESSURE TRANSDUCER – A pressure transducer is an electromechanical device for translating pressure values into an analog electrical signal proportional to the pressure being measured. The analog electronic output typically are in millivolts DC, Volts DC, or milliamps depending on the application. PRESSURE TRANSMITTER – A pressure transmitter is primarily an electronic device which measures pressure but instead of signaling a switch, it merely sends a read-out signal of what the specific pressure value is to a remote location. PROOF TEMPERATURE — The maximum temperature of the media which the sensing portion of the switch can be subjected to without causing permanent damage. RESPONSE TIME OR TIME CONSTANT — The amount of time (in seconds) in which the sensor operates after being subjected to a step temperature increase where the difference between the initial soak temperature and actuation temperature equals 63% of the step temperature. The response time is expressed for a designated flow (feet per second), media and system pressure (PSIG). RISE RATE OR RAMP RATE — The number of degrees (Fahrenheit or Celsius) that the media will increase in a unit of time (minute or second). SEISMIC SHOCK AND VIBRATION — Low frequency, high amplitude waves produced as a result of earth movement. CCS pressure sensors are generally unaffected by seismic shock and vibration. SINGLE POLE DOUBLE THROW (SPDT) SWITCHING ELEMENT — A SPDT switching element has one normally open, one normally closed and one common terminal. Three terminals mean that the switch can be wired with the circuit either normally open (N/O) or normally closed (N/C). SIRA — A world leader in the conformity assessment solutions field, specializing in explosion safety of equipment used in potentially explosive atmospheres (ATEX & IECEx). As a leading Notified Body for Ex Product Certification (ATEX & IECEx), Sira sets the standard with a range of ATEX 137 & DSEAR, ATEX Quality Assurance, IEC 61508 Functional Safety, Training and Personnel Competence Certification services. In 2009, Sira became a CSA International company and provides certification to North American requirements. TEMPERATURE LAG — The number of degrees above the actuation point that the media will be when the sensor operates. The lag is expressed for a designated rise rate (degrees per second), flow (feet per second), and system pressure (PSIG). The lag is determined by multiplying the rise rate by the response time. Example: If a system with a constant flow, pressure, and rise rate of 10 °F per second incorporated a sensor with a response time of 3 seconds, the lag would be 30 degrees. TEMPERATURE SWITCH — A temperature switch is a sensor that upon the increase or decrease of a temperature, opens or closes one or more electrical switching elements at a predetermined set point. THERMOWELL — A housing that can be provided with temperature switches to isolate the temperature probe from the media. UL (Underwriters Laboratories) — A nonprofit corporation engaged in developing standards and testing for safety. Products bearing UL labels have been tested for conformity to UL standards. UL maintains a product surveillance program to ensure continuing conformity to UL standards. UL LISTED PRODUCT — A product that has been tested and complies to UL requirements for reasonably foreseeable hazards associated with the product and is subject to continuing UL product surveillance. UL authorizes the manufacturer to use the UL Listing mark. UL RECOGNIZED COMPONENT — A part or subassembly that has been tested and complies to UL requirements for components used in an end product which complies with UL requirements. The component is subject to continuing UL surveillance. UL authorizes the manufacturer to use the UL Recognized mark. WETTED PARTS — Materials in a sensor that are directly exposed to the media.