Parker CM2115, Руководство пользователя

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62 CM2115
Application Examples
11.5. Using one Analog Input as Two Digital Inputs
The CM2115 allows you to use one analog input as two digital inputs, which is
useful in reducing harness lead or if you are running out of digital inputs in your
system.
To do this, you would connect the analog input to a single pole, double throw
(SPDT) switch.
Note:
You will need to write ladder logic that controls the switch according to
the voltage value readings provided by the analog input. Refer to the
appropriate ladder logic help file, or contact your Parker Vansco Account
Representative for more information on writing ladder logic.
When making the connection, ensure there is a voltage difference between the
two pins on the SPDT switch. This can be done by
 enabling the internal pull-up resistor on the analog input (done through
software)
 adding a resistor to one of the pins on the SPDT switch.
The following shows how to connect an analog input to a SPDT switch:
Internal to product
Analog Input
VBAT
3.3 k
3.3 k
Figure 29: Connecting an analog input to an SPDT switch
11.6. Connecting Various Sensors
There are many types of sensors that can be connected to the CM2115, as follows: