Q020501
Unidirectional propagation qualifier
This qualifier indicates a signal or propagation path with one documented direction.
IEC
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Electrical drawings.
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Symbols, protection codes and equipment references for switchgear, switchboards, switchrooms and microgrids.
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1095 entries · Original illustrations
Installation & communications
Q020502
Simultaneous bidirectional propagation qualifier
This qualifier distinguishes a path supporting propagation in both directions at the same time.
IEC
Q020503
Alternating bidirectional propagation qualifier
This qualifier identifies opposite-direction propagation occurring alternately.
IEC
Q020504
Signal-transmission qualifier
A transmission qualifier identifies the sending role of a signal interface.
IEC
Q020505
Signal-reception qualifier
A reception qualifier identifies the receiving role of a signal interface.
IEC
Q020901
Non-ionising radiation qualifier
This qualifier identifies the publisher's non-ionising radiation family, with the radiation role stated in the device description.
IEC
HAN1B7
Loudspeaker annunciation
A loudspeaker indication identifies conversion of an electrical signal to an audible output.
IEC
HAN1B8
Combined loudspeaker and microphone
This representation identifies an electroacoustic device serving loudspeaker and microphone roles.
IEC
HAN1B9
Microphone input
A microphone indication identifies an acoustic-input transducer in a communications circuit.
IEC
HCN1RSGL
Single power receptacle
This form identifies a single power receptacle connection in the publisher's installation family.
IEC
HCN1RDUP
Duplex power receptacle
This form distinguishes a duplex receptacle arrangement.
IEC
HC01WR_1-
One-line power receptacle
A one-line receptacle represents a power outlet within a simplified circuit view.
IEC
Read the drawing, not just the mark
Small details. Different meanings.
Understand symbols, equipment tags and function numbers—and know when a generic object needs a manufacturer drawing.