Using Analog Channels as Pressure Inputs

Analog channels may be configured to be used as one of three pressure input types. All three modes require the Pressure Control firmware option:

• Pressure Control
  The input is used with the corresponding drive output (in this mode, analog modules without drive outputs cannot be used for pressure control) for closed-loop, pressure control. See Controlling Solely Position, Pressure, or Force for details.

• Auxiliary Pressure
  The input does not have its own drive output. However, pressure control is achieved by sharing a drive output of another input. This is used in applications where an axis switches between closed-loop position control and closed-loop pressure control. See Transitioning from Position to Auxiliary Pressure/Force Control for details.

• Pressure Reference
  The input is used without the drive output. Because no drive output is used, the axis cannot do closed-loop control. This is most often used in cases where the user wishes to have an outside source (such as a joystick or PLC) control the target pressure, in which case another axis will be slaved to the pressure reference input. See Using an External Target Generator for details.

All fields are used as described in the pressure/force status, command, and parameter field topics, except when pressure reference mode is used. In this mode on all parameters are ignored except for Configuration word, Scale A, and Offset A.

Step 1: Assign Analog Channel(s) to be Pressure Input(s)

To assign analog channels as pressure inputs, do the following:

1. On the Tools menu, click Module Configuration.

2. In the Slots list, click an analog module.

3. Click Slot options.

4. In the Analog Channel Assignment dialog box, click the tab of the channel pair (0-1 or 2-3) you wish to assign.

5. Click the option button of a channel assignment that designates one or more channels as Pressure Control, Auxiliary Pressure, and/or Pressure Reference. The assignment selected depends on how you intend to use the all channels.

6. Click Update RMC.

7. The Update Module Configuration dialog box will be displayed to indicate the progress. If the RMC could not be reset automatically, you may be prompted to reset it manually.

8. In the RMC Configuration dialog box, click Close.

The following general steps are necessary for setting up pressure inputs:

Step 2: Configure the Analog Transducer Type for the Pressure Inputs

Refer to Configuring the Analog Transducer Type for details on selecting a voltage or current input type.

Step 3: Set the Scale A and Offset A Parameters for the Pressure Inputs

Refer to the individual field sections for details on setting these parameters.

Analog Input Ranges

See the COUNTS topic for detailed information on the maximum and minimum limits of the various analog input ranges.

See also:

Analog Transducer Overview

Analog Transducer Wiring

Analog Transducer Configuration

Using Analog Channels as Position Inputs

Using Analog Channels as Velocity Inputs

Using Analog Channels as Differential Force Inputs

Copyright (c) 1997-2015 by Delta Computer Systems, Inc.