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Good day:
I just tried one of your sample quizzes, and have some disagreement with a few answers.
In: https://instrumentationtools.com/plc-multiple-choice-questions/


How is INPUT data provided by the OUTPUT module?


This picture is misleading, as the “containers” appear to have contents, making it appear as if we should be checking level in the container. There is NO indication that the things are ferrous.


MOST PLCs scan left to right and top-to bottom, so do not allow reverse - logic flow - ergo ECB is usually not a valid path. Electrically yes - logically no.

output
Output data is not sent directly to the field, it must pass through an output module.


Most prox’ sensors indicate that they are sensing, not confirming output. Will have to look at a block diagram of a sensor to check…

![scan|690x272]
(upload://vjzyNPZLh5a9SZ2VtAZ40kqUxhN.png)
Perhaps my error, but I am sure I have seen PLCs with multiple END instructions - i.e. end of subroutines.


I stand by “all of these”


I have NEVER seen a PLC wherein the module would have an address as a device name. Someone might assign it that symbol, but an out-of-the-box module address? Never. There is no indication that the module is in slot 2, but none of the other answers make sense, so the most likely is I:2/2.


Insufficient data!

This website and whoever created it needs to be given a medal of honour.