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Glossary2019-08-29T15:56:03+00:00

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

  1. 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 difference between

the actuation point and the deactuation point of a sensor. 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 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 systems and components.

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 — TThe 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 SWITCH — A pressure switch is an electrical mechanical device that

converts pressure into motion to operate an electrical switching element.

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.