WIRING DIAGRAMS
3/3
Contactor (closing contact)
Brush
Overcurrent release with long inverse adjustable time delay characteristic
Power cut-off of switch- disconnector power with automatic opening
Wattmeter
Overcurrent release for earth fault with short inverse time characteristic
Switch-disconnector
Screen, shield (it may be drawn in any convenient shape)
Current relay for unbalance between phases
Control coil (general symbol)
Ideal current source
Residual current release
Thermal trip unit
Three connections
Relay for detecting lack of phase in a three-phase system
Voltage transformer
Instantaneous overcurrent release
Relay for detecting blocked rotor by means of current measurement
Ammeter
Winding of three-phase transformer, connection star
Lamp, general symbol
Overcurrent release with short adjustable time delay characteristic
Primary cell, secondary cell, battery of primary cell or secondary cell
Motor with excitation in series
M
Overcurrent release with short inverse adjustable time delay characteristic
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