Glossary

Ammeter

Displays operational current

Burst Fire

A burst fire process generates pulses of power at specific times. The “waves” that are created by this are the signals which switch the system ON / OFF

Closed Loop

A closed-loop system monitors the actual output vs the desired output. If there is any difference between these two variances, an error will occur and the system will correct itself to be back in line with the desired output.

Contactor

A contactor is an electromagnetic switch used in an electrical power circuit

Current Transformer

The current transformer measures the flowing current which can then be displayed using a meter

Earth Leakage Circuit Breaker

The earth leakage device interrupts the circuit if a leakage of current to ground/earth is detected

Earth Leakage CT

This device measures the fault current to earth

Earth Leakage Relay

Used in conjunction with the earth leakage CT and circuit breaker to detect and trip in the event of an earth fault

Ex d

Ex d equipment is explosion proof. It is designed to withstand an explosion in the event of a fault internally. Being robust in design will prevent the propogation of flames to the ambient gases.

Ex e

Ex e equipment are products with increased safety and the hazardous area is protected by design. The protection afforded by the enclosure is limited to ingress protection.  The product’s design prevents arcing, sparking and hot spots from occurring.

Fault Reset

This enables you to reset the control panel and restart your processes. The Fault Reset button will only be enabled once the fault has been restored.

Fuse Switch

This can be used instead of an isolator to switch your system ON / OFF and to offer short circuit protection in one device.

Galvanic Barriers

Used in intrisic safe circuits to limit the energy to the device in the field. By limiting the energy it will prevent a spark from occurring.

Hazardous Area

Hazardous areas are places on industrial sites where a potentially flammable or explosive atmosphere may exist. The flammable substance is usually a gas, vapour or dust.

IEC 61439

IEC 61439 is the international standard for low-voltage switchgear and controlgear assemblies.

Isolator

The isolator separates certain parts of the system, thereby creating an ON / OFF function.

Low Voltage

Less than 1000 volts with a risk of electric shock.

MCB – Miniature Circuit Breaker

A miniature circuit breaker is similar to a fuse. They can open a circuit by switching to the OFF position and provide automatic circuit protection.

MCC

A motor control center (MCC) is a combination of multiple enclosed sections with a common power busbar.

Multifunction Meter

This device displays the amps and voltage.

Open Loop

An open loop system only monitors the actual output, and does not analyse the actual output vs desired output.

Outgoing Terminal

These are the field connections.

Programmable Logic Controller (PLC)

Digital computer for controlling outputs based on applying a control logic to the inputs. Commonly used for manufacturing sequence control or implementing control logic to a mechanised process such as robotics or electric heaters.

Proportional Integral Derivative (PID) controller

Temperature inticating controller using PID algorithm to determine the required setpoint against a measured process parameter.

Relay

A switch that is controlled by a separate low power circuit. Smaller than a contactor.

Sensor

Sensors inside a control panel that measure physical quantity in its environment, for example temperature, voltage or current.

Solid-State Relay (SSR)

This device switches ON / OFF when a small external voltage is applied across the control terminals.

Temperature Controller

The temperature controller has an alarm point function. It can either increase or decrease the output, depending on the settings.

Thermostat

Typically a bimettalic or wax bulb switch that operates at a predetermined temperature. Can be made to be adjustable.

Thyristor

Thyristors are solid-state semiconductors. They have four layers of alternating N and P-type materials (a P-N-P-N structure). Thyristors conduct electric current and control the power circuit.

Thyristor Triggers

A thyristor trigger varies the output of the thyristor.

Transformer

This device converts voltage, for example 690V to 230V or 380V to 115V

Transmitter

The transmitter is a signal converter, typically used to convert mV or Ohms to an mA output.

Trip Amps

The trip amplifier converts an Analog signal to a Digital output.

Voltmeter

The voltmeter reads and displays operational voltage.