Protection and control

Protection and control panels

Panels that house the relays, control devices, metering and marshalling for a substation or switchboard, built against the scheme drawings.

At a glance

Built to
the scheme drawingsthe drawings are the specification
Contents
relays, control, metering, marshalling
Low voltage assembly standard
IEC 61439 serieswhere the panel is a low voltage assembly
Testing
factory tests against the schemewitnessed where the specification requires
Outline drawing for orientation.Not a photograph of a specific unit. Arrangement, enclosure and dimensions depend on the unit offered.

A protection and control panel is defined by its drawings. The schematic, the wiring diagrams and the equipment list are the specification, and a quotation is only as good as the drawings it is priced against.

The panels usually sit in a substation control room or beside the switchgear, and they connect the relays to the instrument transformers and breakers, to the station supply and to the control system. Factory testing against the scheme, before the panel ships, is where most errors are cheapest to find.

What gets specified

ParameterTypical optionsWhat decides it
Scheme drawingsSchematics, wiring diagrams, equipment listThe designer
DevicesRelays, meters, control switches, indicatorsThe scheme
EnclosureDimensions, IP rating, access front or rearThe room and the owner's standard
Auxiliary supplyDC and AC distribution within the panelThe station supply
MarshallingTerminal arrangement and cable entryThe site cabling
TestingFactory tests and witnessingThe specification

Typical options are the ones buyers most often specify. They are not a list of what is available, which is confirmed per enquiry.

Applicable standards

StandardWhat it covers
IEC 61439-1 and IEC 61439-2Low voltage switchgear and controlgear assemblies
IEC 60255-1Measuring relays and protection equipment, for the relays within
IEC 60529Degrees of protection provided by enclosures

The standard that applies is set by the specification and the destination market. Editions change, so the edition cited in a specification is confirmed in the quotation.

Documents normally requested

DocumentWhat it evidences
Technical datasheetRatings, functions and the variant offered
Type test report or certificateThe design has passed the tests of its standard
Dimensional drawingMounting, cut out and connection positions
Wiring or connection diagramTerminals, auxiliary supply and communication
Settings and configuration filesWhere a device is supplied preconfigured
ManualInstallation, commissioning and operation

Where a device replaces an existing one, the nameplate, model and firmware of the existing device are the most useful documents to send.

What we need to quote accurately

01Scheme drawings, or the single line diagram and a description of the functions
02Equipment list, or the relay and device preferences
03Enclosure dimensions, IP rating and access arrangement
04Auxiliary supply voltages
05Testing and witnessing requirements
06Quantity, destination and required delivery date

Delivery and logistics

Devices are lighter to move than transformers and switchboards, but compatibility is the harder part of the delivery. A replacement breaker has to fit the existing panel, a relay has to fit the cut out and the scheme, and a firmware or communication mismatch can make a correct device unusable on the day.

Delivery dates are stated in each quotation for the specific item offered. We do not publish a general lead time.

Related

Request a quote for this equipment

Send the rating, the voltage and the destination, or submit the specification, drawing or nameplate. Anything missing is raised before it reaches a supplier.