Analog Output (Standard)

Operator Menu Location: Generic Hardware Operators Analog Outputs

Operator Bitmap:

Functional Description:
The Standard Analog Output generic hardware operator provides access to an analog output channel resource in the physical hardware. When the generic operator is linked to a specific hardware resource, it causes that hardware resource to generate a physical signal corresponding to its input pin value.

The operator can treat the input value as the raw signal value to reproduce, in the unit of measure defined by the hardware configuration (e.g., 4-20mA, 0-10V, etc..) For example, if the input pin value is 4, the operator will generate a 4V signal when the hardware is configured for 0-5V. It will also produce a 4V signal if the hardware range is configured 0-10V. And it will generate 4mA signal if the hardware range is set to 4-20mA. Alternatively, the operator can be configured to automatically map the input pin value from a user-defined range to the physical signal range, as follows

Here, y is the output value generated by the physical hardware resource, x is the operator's input value, Xrl and Xrh represent the hardware configuration's raw signal range (e.g., mA, mA), is the user-defined value corresponding to Xrl , and Xnh is the user-defined value corresponding to Xrh . For example, suppose the hardware is configured to produce a 4-20mA signal and is attached to an actuator with a 0-100% stroke range. Then, if the input value were 55%, the operator would generate an output of

User-Defined Properties:
Object Name. A string label that identifies the operator.

Scale. Either Hardware Defined or User Defined. In Hardware Defined mode, the operator generated output matches the input pin value in the unit of measure defined by the hardware configuration. In User Defined mode, the operator maps the input value within a user-defined scaling range linearly proportional to the physical signal range.

Lo Range Scaled Equivalent. The input signal value corresponding to the low end of the physical signal range that the output is to generate when User Defined mode is selected.

Hi Range Scaled Equivalent. The input signal value corresponding to the high end of the physical signal range that the output is to generate when User Defined mode is selected.

Units. Engineering units label used for readability

Comments:
•The value may be greater than the value.
•If the input signal range is outside of the user-defined range, the physical signal may also be outside of the hardware configuration range. For example, suppose the user-defined mappings are set to 0 and 100 and the hardware resource is configured as a 4-20mA output. If the input to the operator is 110, the operator will command the hardware to generate an output of 21.6mA (substitute x=110, mA, mA, , and mA into the equation above). Note that the hardware output may not be able to reproduce the commanded output (depending on the hardware implementation, it may saturate at some value between 20mA and 21.6mA).

See Also:
Analog Output (Standard with Feedback), Analog Input (Standard)