Basic electrical terms and definitions, switchboards and connecting and regulating devices, part 1

I International Electrotechnical Dictionary, Spark Plugs and Connecting and Regulating Apparatus, Part 1

Understanding electricity requires knowing these basic electrical terms.

Spark plugs and connecting and adjusting devices.

Electrotechnical Dictionary

general terms

Distribution devices. A general term applied to a set of main and auxiliary switchgear for the operation, regulation, protection or other control of electrical installations.

Switching equipment (of machine or apparatus). Switchgear relating to the control of a particular circuit, machine or device.

Blocking device. A mechanical, electrical, or other device that makes the operation of an apparatus dependent on the condition or position of one or more devices other than the controlled device.

Sequence of operation. The predetermined order in which a number of operations are performed.

Main circuit of a switching device (contactor, selector, switch, etc.). Any conductive parts of a device included in the circuit that the device is designed to make, break, or change.

Auxiliary circuit of a switching device (contactor, selector, switch, etc.). All conductive parts of a device other than those included in the circuit that the device is designed to make, break, or change.

Pole of switching device. All electrical parts connected to a particular line or phase of the device.

Contact (abstract sense). A condition that occurs when two wires touch.

Types of construction and physical protection

Apparatus immersed in oil. Apparatus in which the main parts or some of these parts are immersed in oil.

Single tank switch. Single Tank Circuit Breaker. A multi-pole switch or circuit breaker with a single oil-filled tank containing the breaking elements of all poles. A switch or circuit breaker in which each pole can operate independently of the others.

Indoor unit. Apparatus intended for use in buildings only.

External device. Apparatus intended for outdoor use.

Open type appliances. Apparatus in which live parts can be touched.

Shielded device. Partially closed apparatus. Apparatus in which live parts are protected from accidental contact by people.

Fully enclosed apparatus. Apparatus completely enclosed in such a way as to make it impossible for foreign bodies to make accidental or intentional contact with a live part as long as the housing is in position. Apparatus protected or enclosed by a metal enclosure which is normally earthed.

Metal Clad Appliances. Apparatus in which the components are encased in a grounded (grounded) metal housing mounted on the enclosed conductors and insulation and can be assembled relative to each other to form a self-contained structure.

Fireproof apparatus. Appliances designed to operate in a flammable atmosphere and so constructed that they cannot ignite the surrounding atmosphere during operation under specified conditions.

Structural elements

Terminal. A conductive element around an apparatus intended for connection to external conductors.

Ground terminal. Ground terminal. A terminal designed to provide, through a special connection, the grounding grounding) of a part of the apparatus.

Contact member (abbreviated: contact). A conductor designed to cooperate with another to establish contact.

Contacts (specific meaning). Two or more interacting contact elements relatively movable to open or close a circuit.

Main contacts. Contacts introduced in the main circuit of the apparatus. For contact members consisting of more than one element, the primary contacts are the interacting elements that normally carry most of the current.

Arc contact. The contact on which the arc is drawn after the main (and intermediate, when used) contacts have separated.

Auxiliary contact. A contact introduced into the auxiliary circuit of the apparatus.

Earth contact. Ground contact. A contact used to earth (ground) parts of a device.

Normally open auxiliary contacts. Normally open interlock. Auxiliary contacts of a switch or circuit breaker that are open when the switch or circuit breaker is open.

Normally closed auxiliary contacts. Simple lock closure. Auxiliary contacts of a switch or circuit breaker that close when the switch or circuit breaker is open.

Vacation contact. Normally closed interlock. Auxiliary contact of a device having only one rest position. This contact closes when the device is turned off.

Work contact. Normally open interlock. Auxiliary contact of a device having only one rest position. This contact is open when the device is turned off.

Rear contacts. A contact device in which the relative motion of the cooperating members is substantially in a direction perpendicular to the contact surface.

Sliding contacts. A contact device in which the relative motion of the cooperating members is substantially in a direction parallel to the contact surface.

Movable contacts. A contact arrangement where one cooperating member rolls over the other.

Fixed contact. The stationary part, rigidly fixed, of the contact element.

Plug. A detachable element connected to one or more conductors that is designed to be inserted into a socket of suitable shape to establish one or more connections.

Attaching a plug. Plug. A detachable element, usually shaped like a truncated cone and not connected to any conductor, designed to make contact when placed between two contacts.

PIN. A conductive element, rigid or flexible, intended to be inserted into contact with a suitably shaped socket so as to make electrical contact.

Socket-contact. A conductive element, rigid or flexible, designed to receive a suitable pin to make electrical contact.

Movable element (of apparatus). The movable part of an apparatus which carries the movable contact element and whose movement performs the operation (making and breaking).

Fixator (of apparatus). A device which holds the movable element of the apparatus in a set position against the action of springs or gravity.

Shutdown device. A device which, by mechanically acting on a latching mechanism, allows stored energy to open a circuit breaker.

Resetting the device… A device by which a detent mechanism is returned to its set position, from which the apparatus can be again actuated.

Arc control device. A chamber that partially or completely surrounds the contacts of a switch or circuit breaker designed to contain the arc and assist in extinguishing it.

Arch chute. A camera where the drc is transferred to help extinguish it.

Blower coil. A coil designed to produce a magnetic field arranged to deflect an arc, e.g. g. in an arcuate chute.

Press the button. A part of an electrical device consisting of a button that must be pressed to perform an operation.

Cable input. A device allowing the passage of a cable through a partition or the housing of an apparatus.

Bush. A device allowing the passage of a wire through a partition or housing of an apparatus.

Compression gland. Cable entry providing a seal by compressing a deformable material.

Bushing. An insulating structure incorporating a through conductor or providing a passage for such a conductor, capable of being mounted on a bulkhead.

Device base. The fixed part of a device on which its components are mounted.

Device location. A device designed to ensure that a movable element of an apparatus (e.g. a controller) is placed in one of many specified positions.

Operation

Manual control. Operation control through human intervention.

Automatic control. Control of an operation, without human intervention, in response to the occurrence of a predetermined condition.

Local control. Control of an operation from a device located on or near the controlled device.

Remotely. Remote operation control: this involves a connection, usually electrical, between the controlling device and the device to be controlled.

Hand surgery. Starting the device manually without additional power supply.

Power supply. Actuation of an apparatus with electric, spring, pneumatic or hydraulic power.

Sensory. Running. Energizing a motor or solenoid repeatedly for short periods to produce small movements of the actuator.

Independent manual work. A manual operation in which the energy stored during the initial part of the operation is later used to complete the closing operation independently of the operator.

Apparatus with automatic control. A device containing elements that are sensitive to changes in a physical quantity that unlock the device under predetermined conditions.

Thermally controlled device. A device which is actuated by the thermal effect of a current passing through it.

No shutdown (circuit breaker). A circuit breaker provided with a device that overrides any attempt to hold it closed when predetermined conditions are established requiring it to be opened.

Locking device (switch with ...). A circuit breaker equipped with a device that overrides any attempt to close the circuit breaker when predetermined conditions requiring its opening are established.

Automatic switch. Circuit breaker provided with rpeans for automatic reclosing after opening under fault conditions.

An instant-acting device. Apparatus in which work is performed when a predetermined condition (for example, a current or voltage value) is reached.

Time delay device. Apparatus in which the operation takes place some time after the time when the conditions are established which make it work.

A definite time delay (switch, release or relay). A time-delay circuit breaker, release, or relay in which the time delay is independent of the magnitude of the quantity causing operation.

Reverse time delay (switch, release or relay). A time-delay switch, release, or relay in which the time delay varies inversely with the magnitude of the quantity causing operation.

Overcurrent [overvoltage] release. A device that operates automatically when the current flowing through it or the voltage applied to it exceeds a predetermined value.

Release the undercurrent [under voltage]. A device that operates automatically when the current flowing through it or the voltage applied to it falls below a predetermined value.

Release of reverse current (direct current). A device which operates automatically when the direct current through it has reversed its normal direction.

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