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Examoogle • User • info@examoogle.com • EE-2024-8821
Chapter 1 of 12 • Page 1 of 248🔒 Protected PDF • Watermarked
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If current flow from output module to load it is known as_____.
Sourcing
Sinking
Sinking
Quick Summary: In PLC terminology, the term 'sinking' refers to a configuration where the output module provides a return path for the current to ground. When the output is activated, the load receives current from the external source, and the PLC output module 'sinks' that current to the common terminal.
In PLC terminology, the term 'sinking' refers to a configuration where the output module provides a return path for the current to ground. When the output is activated, the load receives current from the external source, and the PLC output module 'sinks' that current to the common terminal.
Iload=RloadVsupply — Ohm's Law governing the current flow in the sinking loop
In a sinking configuration, the positive terminal of the power supply is connected to the load, and the negative (or common) terminal is connected to the PLC output module. When the output transistor/switch turns ON, it completes the circuit to ground (0V), allowing current to flow from the supply, through the load, and into the module's terminal.
Sinking: The PLC module acts as the path to ground (sink).
Sourcing: The PLC module acts as the source of current to the load.
The designation depends on the direction of current flow relative to the PLC terminal.
This is critical for interfacing PLC I/O with sensors and actuators (PNP/NPN).
Sinking outputs are common in NPN-based transistor logic.
Allows direct control of devices connected to a common positive rail.
Requires careful consideration of signal commonality.
Incorrect wiring can lead to permanent damage of the output transistor.
Direct drive of relay coils.
Interfacing with NPN proximity sensors.
Industrial automation switching.
| Feature | Sourcing | Sinking |
|---|---|---|
Current Path | Source to Load | Load to Ground |
In many industrial contexts, 'Sinking' is associated with NPN-type circuits where the device switches the ground.
If the current flows FROM the module TO the load, it is Sourcing (the opposite of the question provided).
B is correct — In sinking configuration, the PLC output module provides the path to common (ground) for the load current.
Always remember: 'Sinking' = Current flows into the module; 'Sourcing' = Current flows out of the module.