Automation and Control Guides Page 2: 198 technical guides for choosing Automation and Control products: selection criteria, standards, common mistakes and frequently asked questions.
What Is a PLC Connection Module? Types and Selection Criteria — A PLC connection module distributes the 24 V DC, 0 V or earth potential of sensors and actuators to many connection points at an I/O station. What Is a Photoelectric Sensor Reflector? Types and Selection Criteria — A photoelectric sensor reflector is a passive optical part, usually built from corner-cube prisms, that returns the light of a retroreflective photoelectric sensor in the direction it came from. What Is a PLC Power Module? Types and Selection Criteria — A PLC power module is a supply module that provides operating power or extra supply to the modules in a PLC rack or I/O station and works only with its own series. What Is a Digital Frequency Meter? Housing Types and Selection Criteria — A digital frequency meter is a panel-mount measuring device that shows the frequency of the AC line it is connected to in hertz (Hz) on a numeric display. What Is a Flasher Timer Relay? Types and Selection Criteria — A flasher timer relay is a timer relay that energises and releases its output contact in turn for set working (ON) and pause (OFF) times until the supply is removed. What Is a Relay Jumper Bar? Types and Selection Criteria — A relay jumper bar is a comb-shaped part fitted on top of relay sockets lined up on a DIN rail to link their same-function terminals. What Is a Maintained Push Button? Types and Selection Criteria — A maintained push button is a panel and machine control button that stays in the pressed position and keeps its contact changed until it is pressed again. What Is a Sensor Fiber Optic Cable? Types and Selection Criteria — A sensor fiber optic cable is a light guide with a threaded end that carries a fiber optic amplifier's light to the sensing point and the returning light back. What Is a Crane Control Spare Part? Types and Selection Criteria — A crane control spare part is a part of a pendant crane control, such as a button head, contact block or adapter, that is renewed without replacing the whole station. What Is a Light Barrier? Types and Selection Criteria — A light barrier is an area-scanning optical sensor that monitors parallel beams from a transmitter bar with a receiver bar opposite and gives an output when a beam is interrupted. What Is a Photocell Relay? Types and Selection Criteria — A photocell relay is a twilight switch that measures ambient light with a photocell eye and switches lighting on when it gets dark and off when it gets light. What Is a Measuring Shunt? Rated Current Selection and Wiring — A measuring shunt is a precise low-value resistor that produces a millivolt voltage proportional to the direct current through it, so a mV-input ammeter can read high DC current. What Is an Analog Input Module? Types and Selection Criteria — An analog input module is an expansion module that converts continuous signals such as 4-20 mA or 0-10 V from transmitters and sensors into digital values for the PLC. What Is an Industrial Ethernet Switch? Types and Selection Criteria — An industrial Ethernet switch is a DIN-rail network switch inside a panel that joins PLCs, HMIs, drives and remote I/O stations on the same Ethernet network. What Is an Astronomical Timer Relay? Types and Selection Criteria — An astronomical timer relay is a digital timer relay that calculates sunrise and sunset from location and date and switches lighting on and off without a light sensor. What Are Limit Switch Spare Parts? Choosing Contact Blocks and Safety Actuators — Limit switch spare parts are the parts used to renew a worn contact block of a limit switch or the actuator of a door safety switch without replacing the housing. What Is an NTC Temperature Probe? Types and Selection Criteria — An NTC temperature probe is a temperature sensor in which a thermistor whose resistance falls as temperature rises is enclosed in a protective sheath and cabled for NTC-input devices. What Is a Rectangular DC 3-Wire Inductive Sensor? Types and Selection Criteria — A rectangular DC 3-wire inductive sensor is a proximity sensor with a slim 8×8 mm prismatic housing that detects metal parts without contact in tight spaces. What Is a Universal Controller? Types and Selection Criteria — A universal controller is a process controller that reads a transmitter's current or voltage signal and gives a relay or SSR output according to the setpoint. What Is a Programmable Timer Relay (Time Switch)? Types and Selection Criteria — A programmable timer relay (time switch) is a switching device that automatically turns a load on and off by a program set for the time of day and day of the week. What Is a Steel Head Inductive Sensor? Types and Selection Criteria — A steel head DC 3-wire inductive sensor is an all-metal proximity sensor with a steel sensing face that detects metal without contact at points exposed to chips and impacts. What Is a PLC Temperature Module? Types and Selection Criteria — A PLC temperature module is an analog input module that connects sensors such as thermocouples and PT100 directly to the PLC and converts their signals into temperature. What Are Sirens and Buzzers? Types and Selection Criteria — Sirens and buzzers are audible warning devices that announce conditions such as a fault, danger or a shift change with sound and, in some types, light as well. What Is a Thermocouple Plug and Socket? Types and Selection Criteria — A thermocouple plug and socket is a J- or K-type connector that joins a thermocouple probe or compensation cable detachably without causing measurement error.