Analog Outputs

The FAC-2100 contains two analog outputs that can operate in a voltage or current output mode.

Select from one of the following modes to get additional information:

Disconnect Switch and Voltage Feedback

Each analog output contains both an internal on/off disconnect switch and a voltage feedback monitor mechanism as shown in the following diagram:

This mechanism is useful to:

1. Provide a diagnostic to monitor the analog output signal for issues. For example, if a 4-20mA output signal is driving a 250 ohm device, the voltage monitor should measure a voltage equal to the current output times 250 ohms. Or, if the channel is in voltage mode, use the monitor the verify the output level is what the program is requesting. If it does not match, an error can be called.
2. Disconnect the analog output signal from the actuator device in applications where two redundant analog outputs are driving the actuator. In this case the voltage monitor can measure the voltage output from the redundant pair while the controller's output is in standby.
3. Create additional analog inputs. In cases where the application requires more analog inputs and does not need all the analog outputs, disconnect the analog output signal and use the voltage monitor as an additional analog input channel. The monitor channel does not have as much resolution as a standard input channel, but in many applications it is sufficient.