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Module Specific

Module Specific Terms

Module Specific Terms
TermDefinition
AnalogA type of signal or data that varies continuously over a range, representing values like temperature, pressure, or voltage.
Analog-to-Digital (AD)The process of converting analog signals to digital signals.
Analog-to-Digital/Digital-to-Analog (AD/DA)The process of converting analog signals to digital signals and digital signals to analog signals in a combo module.
Central Processing Unit (CPU)The central processing unit (CPU) is the primary component of a PLC that is responsible for executing program instructions, processing logic, and managing input and output operations.
CurrentThe flow of electric charge, measure in amperes (A or amps), representing the movement of electrons through a conductor.
Digital-to-Analog (DA)The process of converting digital signals to analog signals.
DIN RailStandardized metal rail used for mounting industrial control components, such as PLCs, relays, and terminal blocks, within electrical enclosures.
Hysteresis

A control or measurement feature where a set threshold includes a margin of tolerance to prevent frequent switching or rapid oscillation.
Commonly used in analog signal processing (e.g., temperature, pressure) to avoid instability by creating a buffer zone between the "on" and "off" states.

Input/Output (I/O)Interfaces in a PLC that connect the system to external devices.
Inputs receive signals from sensors and other devices while outputs send control signals to actuators, relays, or components.
Interposing RelayA relay used as an interface between two different systems or voltage levels within a control circuit.
It acts as an intermediary, typically isolating the PLC's low voltage control from higher-voltage devices or components, protecting the PLC from voltage spikes and allowing safe control of heavy-duty equipment.
Japanese Platinum 100 (JPT100)A type of resistance temperature detector (RTD) made from platinum with a resistance of 100Ω at 0°C (32°F).
The temperature coefficient is typically 0.003916Ω.
LoadA device or component that consumes electrical power to perform work.
In control circuits, the load is the component or device that is activated or driven by a power source.
Negative-Positive-Negative (NPN)A type of transistor or sensor configuration where the device provides a path to ground.
The output switches from high to low when activated.
Nickel 1000 (Ni1000)A type of resistance temperature detector (RTD) made from nickel with a resistance of 1000Ω at 0°C (32°F).
The temperature coefficient is typically 0.00618Ω.
Platinum 100 (PT100)A type of resistance temperature detector (RTD) made from platinum with a resistance of 100Ω at 0°C (32°F).
The temperature coefficient is typically 0.00385Ω.
Platinum 1000 (PT1000)A type of resistance temperature detector (RTD) made from platinum with a resistance of 1000Ω at 0°C (32°F).
The temperature coefficient is typically 0.00385Ω.
PositioningThe control of a machine or actuator's position.
Positive-Negative-Positive (PNP)A type of transistor or sensor configuration where the device supplies positive voltage to the load.
The output switches from low to high when activated.
Process Data Object (PDO)A type of message used to exchange process data between devices in real-time.
Programmable Logic Controller (PLC)The programmable logic controller (PLC) is a computer used in industrial automation to control machinery, processes, and systems by executing programmed logic based on input and output signals.
Proportional-Integral-Derivative (PID)A control algorithm used in automation that continuously calculates error values and adjust control outputs accordingly.
This provides stable and precise control over processes.
PulseA signal, short duration electrical signal or burst, often used in counting, timing, and control applications.
Pulse Train Output (PTO)A method for generating a sequence of pulses with a controlled frequency and duration.
Pulse Width Modulation (PWM)A technique for controlling the amount of power delivered to a device by varying the width of pulse in a signal.
Real-Time Clock (RTC)A clock that keeps track of the current date and time allowing PLCs to perform time-based operations.
RelayAn electrically operated switch used to control high-power devices with a low-power signal.
Commonly used to control outputs or isolate circuits.
Resistance Temperature Detector (RTD)A temperature sensor that uses the predictable change in electrical resistance of certain materials to measure temperature.
SinkA type of electrical configuration where the current flows from the load into the PLC's input module.
The device provides a path to ground.
The flow is NPN (negative-positive-negative).
SourceA type of electrical configuration where the current flows from the PLC's output module to the load.
The device provides a positive voltage to the load.
The flow is PNP (positive-negative-positive).
ThermistorA temperature-sensitive resistor whose resistance changes significantly with temperature changes, commonly used in temperature monitoring and control applications.
Thermocouple (TC)A temperature sensor that generates a small voltage based on the temperature difference between two different metals joined at one end.
Thermocouple Type: BA platinum-rhodium thermocouple used for extremely high temperatures.
Temperature range: 0°C ~ 1,700°C (32°F ~ 3,092°F)
Thermocouple Type: EA nickel-chromium/constantan thermocouple used for low temperatures or cryogenic applications.
Temperature range: -200°C ~ 900°C (-328°F ~ 1,652°F)
Thermocouple Type: JAn iron/constantan thermocouple used in non-oxidizing environments.
Temperature range: -40°C ~ 750°C (-40°F ~ 1,382°F)
Thermocouple Type: KA nickel-chromium/nickel-alumel thermocouple used for general-purpose applications.
Temperature range: -200°C ~ 1,260°C (-328°F ~ 2,300°F)
Thermocouple Type: NA nicrosil/nisil thermocouple used as a more stable and oxidation-resistant alternative to type K thermocouples.
Useful for high temperatures.
Temperature range: -200°C ~ 1,260°C (-328°F ~ 2,300°F)
Thermocouple Type: RA platinum/platinum-rhodium thermocouple used for laboratory and industrial applications requiring accurate high-temperature measurements.
Temperature range: -0°C ~ 1,480°C (32°F ~ 2,696°F)
Thermocouple Type: SA platinum/platinum-rhodium thermocouple used for high-temperature measurements typically used in pharmaceutical and biotech industries.
Temperature range: 0°C ~ 1,480°C (32°F ~ 2,696°F)
Thermocouple Type: TA copper/constantan thermocouple used for laboratory and cryogenic applications
Temperature range: -200°C ~ 370°C (-328°F ~ 698°F)
TransistorA semiconductor device used to amplify or switch electronic signals and electrical power.
It is a key component in digital and analog circuits
VoltageThe electrical potential difference between two points, measured in volts (V), which drives current flow in a circuit.