Converts received voltage or current levels into numerical values. You can store and process these values within the logic controller.
A program including configuration data, symbols, and documentation.
(American standard code for Information Interchange) A protocol for representing alphanumeric characters (letters, numbers, certain graphics, and control characters).
(boot application) The binary file that contains the application. Usually, it is stored in the controller and allows the controller to boot on the application that the user has generated.
(bootstrap protocol) A UDP network protocol that can be used by a network client to automatically obtain an IP address (and possibly other data) from a server. The client identifies itself to the server using the client MAC address. The server, which maintains a pre-configured table of client device MAC addresses and associated IP addresses, sends the client its pre-configured IP address. BOOTP was originally used as a method that enabled diskless hosts to be remotely booted over a network. The BOOTP process assigns an infinite lease of an IP address. The BOOTP service utilizes UDP ports 67 and 68.
(bit per second) A definition of transmission rate, also given in conjunction with multiplicator kilo (kbps) and mega (mbps).
A mounting device that is designed to seat an electronic module on a DIN rail and connect it to the TM5 bus for M258 and LMC058 logic controllers. Each base bus extends the integrated TM5 data and electronic power buses as well as the 24 Vdc I/O power segment. The electronic modules are added to the TM5 system through their insertion on the base bus.
The process of setting or maintaining the accuracy of a measuring device by comparing its value to a known and correct standard.
(controller area network) A protocol (ISO 11898) for serial bus networks, designed for the interconnection of smart devices (from multiple manufacturers) in smart systems and for real-time industrial applications. Originally developed for use in automobiles, CAN is now used in a variety of industrial automation control environments.
An open industry-standard communication protocol and device profile specification (EN 50325-4).
(continuous function chart) A graphical programming language (an extension of the IEC 61131-3 standard) based on the function block diagram language that works like a flowchart. However, no networks are used and free positioning of graphic elements is possible, which allows feedback loops. For each block, the inputs are on the left and the outputs on the right. You can link the block outputs to the inputs of other blocks to create complex expressions.
(CAN in automation) A non-profit group of manufacturers and users dedicated to developing and supporting CAN-based higher layer protocols.
continuous function chart language
A graphical programming language (an extension of the IEC61131-3 standard) based on the function block diagram language that works like a flowchart. However, no networks are used and free positioning of graphic elements is possible, which allows feedback loops. For each block, the inputs are on the left and the outputs on the right. You can link the block outputs to inputs of other blocks to create complex expressions.
A network containing logic controllers, SCADA systems, PCs, HMI, switches, ...
Two kinds of topologies are supported:
oflat: all modules and devices in this network belong to same subnet.
o2 levels: the network is split into an operation network and an inter-controller network.
These two networks can be physically independent, but are generally linked by a routing device.
Automates industrial processes (also known as programmable logic controller or programmable controller).
An undesired signal caused by a capacitive, inductive, or conductive coupling between 2 channels.
(Canadian standards association) The Canadian standard for industrial electronic equipment in hazardous environments.
(clear to send) A data transmission signal and acknowledges the RDS signal from the transmitting station.
The cyclic scan time has a fixed duration (interval) specified by the user. If the current scan time is shorter than the cyclic scan time, the controller waits until the cyclic scan time has elapsed before starting a new scan.
A reduction in an operating specification. For devices in general, it is usually a specified reduction in nominal power to facilitate operation at increased ambient conditions like higher temperatures or higher altitudes.
(dynamic host configuration protocol) An advanced extension of BOOTP. DHCP is more advanced, but both DHCP and BOOTP are common. (DHCP can handle BOOTP client requests.)
(digital input/output) An individual circuit connection at the electronic module that corresponds directly to a data table bit. The data table bit holds the value of the signal at the I/O circuit. It gives the control logic digital access to I/O values.
(Deutsches Institut für Normung) A German institution that sets engineering and dimensional standards.
EN identifies one of many European standards maintained by CEN (European Committee for Standardization), CENELEC (European Committee for Electrotechnical Standardization), or ETSI (European Telecommunications Standards Institute).
A device for length or angular measurement (linear or rotary encoders).
A part of a machine including sub-assemblies such as conveyors, turntables, and so on.
A physical and data link layer technology for LANs, also known as IEEE 802.3.
FAST input/output Specific I/O modules with some electrical features (for example, response time) while the treatment of these channels are done directly by the controller
(function block diagram) One of 5 languages for logic or control supported by the standard IEC 61131-3 for control systems. Function block diagram is a graphically oriented programming language. It works with a list of networks, where each network contains a graphical structure of boxes and connection lines, which represents either a logical or arithmetic expression, the call of a function block, a jump, or a return instruction.
(functional Earth) A common grounding connection to enhance or otherwise allow normal operation of electrically sensitive equipment (also referred to as functional ground in North America).
In contrast to a protective Earth (protective ground), a functional earth connection serves a purpose other than shock protection, and may normally carry current. Examples of devices that use functional earth connections include surge suppressors and electromagnetic interference filters, certain antennas, and measurement instruments.
Represents the BIOS, data parameters, and programming instructions that constitute the operating system on a controller. The firmware is stored in non-volatile memory within the controller.
(file transfer protocol) A standard network protocol built on a client-server architecture to exchange and manipulate files over TCP/IP based networks regardless of their size.
A programming unit that has 1 input and returns 1 immediate result. However, unlike FBs, it is directly called with its name (as opposed to through an instance), has no persistent state from one call to the next and can be used as an operand in other programming expressions.
Examples: boolean (AND) operators, calculations, conversions (BYTE_TO_INT)
A programming unit that has 1 or more inputs and returns 1 or more outputs. FBs are called through an instance (function block copy with dedicated name and variables) and each instance has a persistent state (outputs and internal variables) from 1 call to the other.
Examples: timers, counters
(human machine interface) An operator interface (usually graphical) for human control over industrial equipment.
(high-speed counter) A function that counts pulses on the controller or on expansion module inputs.
(input/output)
(international electrotechnical commission) A non-profit and non-governmental international standards organization that prepares and publishes international standards for electrical, electronic, and related technologies.
Part 3 of a 3-part IEC standard for industrial automation equipment. IEC 61131-3 is concerned with controller programming languages and defines 2 graphical and 2 textual programming language standards. The graphical programming languages are ladder diagram and function block diagram. The textual programming languages include structured text and instruction list.
A special function that helps reject extraneous signals on input lines due to such things as contact bounce and inducted electrical transients. Inputs provide a level of input filtering using the hardware. Additional filtering with software is also configurable through the programing or the configuration software.
(Internet protocol) Part of the TCP/IP protocol family that tracks the Internet addresses of devices, routes outgoing messages, and recognizes incoming messages.
(ingress protection) The protection classification according to IEC 60529 offered by an enclosure, shown by the letter IP and 2 digits. The first digit indicates 2 factors: helping protect persons and for equipment. The second digit indicates helping protect against water. IP 20 devices help protect against electric contact of objects larger than 12.5 mm, but not against water.
(ingress protection) The protection classification according to IEC 60529. IP 67 modules are protected against ingress of dust, contact, and water up to an immersion depth of 1 m.
(light emitting diode) An indicator that illuminates under a low-level electrical charge.
Consists of several functions and/or equipment.
A processor task that is run through its programming software. The MAST task has 2 sections:
oIN: Inputs are copied to the IN section before execution of the MAST task.
oOUT: Outputs are copied to the OUT section after execution of the MAST task.
The protocol that allows communications between many devices connected to the same network.
(millisecond)
(not connected)
A system of interconnected devices that share a common data path and protocol for communications.
An addressable device on a communication network.
(peripheral component interconnect) An industry-standard bus for attaching peripherals.
(power distribution module) A module that distributes either AC or DC field power to a cluster of I/O modules.
(Protective Earth) A common grounding connection to help avoid the hazard of electric shock by keeping any exposed conductive surface of a device at earth potential. To avoid possible voltage drop, no current is allowed to flow in this conductor (also referred to as protective ground in North America or as an equipment grounding conductor in the US national electrical code).
(Profibus decentralized peripheral) An open bus system uses an electrical network based on a shielded 2-wire line or an optical network based on a fiber-optic cable. DP transmission allows for high-speed, cyclic exchange of data between the controller CPU and the distributed I/O devices.
A convention or standard definition that controls or enables the connection, communication, and data transfer between 2 computing system and devices.
(pulse width modulation) A fast output that oscillates between off and on in an adjustable duty cycle, producing a rectangular wave form (though you can adjust it to produce a square wave).
Among the outputs of HSC are the reflex outputs associated to a threshold value that is compared to the counter value depending on the configuration of the HSC. The reflex outputs switch to either on or off depending on the configured relationship with the threshold.
(real-time clock) A battery-backed time-of-day and calender clock that operates continuously, even when the controller is not powered for the life of the battery.
(request to send) A data transmission signal and CTS signal that acknowledges the RTS from the destination node.
(remote terminal unit ) A device that interfaces with objects in the physical world to a distributed control system or SCADA system by transmitting telemetry data to the system and/or altering the state of connected objects based on control messages received from the system.
A command that causes the controller to scan the application program, read the physical inputs, and write to the physical outputs according to solution of the logic of the program.
The line that receives data from one source to another.
A function that includes:
oreading inputs and placing the values in memory
oexecuting the application program 1 instruction at a time and storing the results in memory
ousing the results to update outputs
(sequential function chart) A language that is composed of steps with associated actions, transitions with associated logic condition, and directed links between steps and transitions. (The SFC standard is defined in IEC 848. It is IEC 61131-3 compliant.)
A wiring arrangement in which the device provides current to the input electronic module. A sink input is referenced to 0 Vdc.
(simple network management protocol) A protocol that can control a network remotely by polling the devices for their status and viewing information related to data transmission. You can also use it to manage software and databases remotely. The protocol also permits active management tasks, such as modifying and applying a new configuration.
A wiring arrangement in which the output electronic module provides current to the device. A source output is referenced to +24 Vdc.
(structured text) A language that includes complex statements and nested instructions (such as iteration loops, conditional executions, or functions). ST is compliant with IEC 61131-3.
A group of sections and subroutines, executed cyclically or periodically for the MAST task or periodically for the FAST task.
A task possesses a level of priority and is linked to inputs and outputs of the controller. These I/O are refreshed in relation to the task.
A controller can have several tasks.
(terminal block) The component that mounts in an electronic module and provides electrical connections between the controller and the field devices.
The line that sends data from one source to another.
(underwriters laboratories) A US organization for product testing and safety certification.
