The two actions that can be activated with the discrete inputs on an SC200 are as follows:
1) Set a controller warning.
2) Hold/Transfer the outputs (analog and relay) for either or both of the sensors.
The SC200 discrete inputs can be configured using the jumpers on the back of the main board to either accept a voltage input (in this mode the input circuit is isolated with an opto-coupler) or contact switch closure to trigger the input (in this mode the SC200 supplies a non-isolated 12V to connect to the switch).


The instructions for programming the SC200 discrete inputs can be found in the "Full" version of the user manual (provided below for reference):
Set up the discrete inputs
Use these inputs as switch closure inputs or logic level voltage inputs.
1. Press the MENU key.
2. Select SC200 Setup and push ENTER .
3. Select Discrete Input Setup and push ENTER .
4. Select the desired channel (Input 1, Input 2 or Input 3) and push ENTER .
5. Select a control logic option and push ENTER .
Option Description
Disable This channel is disabled and not used.
On/High This channel is active when either the switch input is On (or closed), or the logic level voltage input is at a High level.
Off/Low This channel is active when either the switch input is Off (or opened), or the logic level voltage input is at a Low level.
6. Select a warning option and push ENTER .
Option Description
Off An active discrete input does not trigger a device warning.
On An active discrete input triggers a device warning.
7. Select an output mode option and push ENTER .
Option Description
Active Output level continues to represent operating conditions.
Hold Output level is held static.
Transfer Output level moves to a pre-configured value.
8. Select the sensors that will have their outputs (analog and relay) affected when one of the discrete inputs becomes active. Push ENTER .
9. Use the arrows to select the On Delay value (the duration time delay between the discrete input activation and the configured response of the controller). Push ENTER .
10. Use the arrows to select the Off Delay value (the duration time delay between the discrete input de-activation and the configured response of the controller). Push ENTER .
11. Repeat steps 4-10 for each desired channel.
12. If a discrete input needs to be changed after initially set up:
a. Repeat steps 1-4 and an Input Settings menu appears with the
following options:
• Control Logic
• Set Warning
• Output Mode
• On Delay
• Off Delay
b. Select the desired option and push ENTER .
c. Make the desired changes and push ENTER to save the changes and return to the Inputs Setting menu.