Hello !
http://support.automation.siemens.com/W ... 0=10805384
The above link shows the SIMATIC Modules wiring configuration for sourcing and sinking.
In case of O/P Modules, Siemens is using PNP and NPN configured transistors at its O/P stage.
Can we not connect the load to the Emitter of PNP Transistor in order to operate it as a Sinking O/P rather than Sourcing?
Similarly, in case of NPN Transistor, can we not connect the load to its Emitter to make it Sourcing instead of sinking?
(Or is it all about the "load has to be always on the Collector terminal" and so we have to accept this sourcing and sinking "philosophy" for SIMATIC O/P Modules?)
Plz bear with my question. Thanks in advance.
Regards
[?]: Sourcing / Sinking I/O Modules with PNP/NPN transistors
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nashama
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emulefan
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Re: [?]: Sourcing / Sinking I/O Modules with PNP/NPN transis
The answer is very simple.
The outputs comes in groups (usually 8 ), these outputs have a common terminal.
For sourcing outputs the common terminal is +V, so you have all the transistor emmiters of the 8 outputs connected to this +V terminal and you have independent collector terminals for each output. Then you can not connect the load in the transistor emmiter.
For the sinking outputs the common terminal is -V, and again you have the collector transistor alone and the emmiters connected to the common terminal.
Regards
The outputs comes in groups (usually 8 ), these outputs have a common terminal.
For sourcing outputs the common terminal is +V, so you have all the transistor emmiters of the 8 outputs connected to this +V terminal and you have independent collector terminals for each output. Then you can not connect the load in the transistor emmiter.
For the sinking outputs the common terminal is -V, and again you have the collector transistor alone and the emmiters connected to the common terminal.
Regards