Technical description Chapter 6
PA 7300
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6.2.4 Cabling 20 mA Current Loop
Active / passive :
When a transmitter and a receiver communicate, one of them
has to supply the necessary current. If the transmitter supplies the current, it is
active. The receiver is passive.
In reverse, if the receiver supplies the current, it is active.
Fig. 6-6: Active transmission / active reception
Fig. 6-7: Active transmission / passive reception
Fig. 6-8: Passive transmission / active reception
