Hach LXV525.99A15551, User Manual

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6.5.2 Configure the analog outputs
Make sure that a 4-20 mA output module is installed in the controller. Refer to the documentation
supplied with the module. Make sure that all of the necessary electrical connections are complete
before the 4-20 mA output is configured.
1. Identify the relation between input current and calculated concentration as follows:
• Identify what analog output range uses the connected device (0-20 mA or 4-20 mA).
• Identify the maximum concentration that is equal to the 20 mA on the analog output.
• Identify the minimum concentration that is equal to the 0 or 4 mA on the analog output.
2. Push the main menu icon, then select Outputs > mA outputs > System setup
The available channels based on the installed expansion modules show.
3. Enter the settings for each channel.
Option Description
Source Selects the analog output to configure. For the selected device, select the parameter that
set the measurement options.
Parameter Changes the parameter selected on the source option.
Data view Sets the measured value that shows on the display and saves to the data log. Options:
Input value (default) or Current.
Function Sets the output function. Setup options change based on the selected function.
• Linear control—Signal is linearly dependent on the process value.
• PID control—Signal works as a PID (Proportional, Integral or Derivative) controller.
Transfer Sets the transfer value shown on the analog output when the selected source reports an
internal error, is disconnected from the system or its output mode is set to Transfer.
Default: 10 mA
Current Shows the calculated output current (in mA). By default, the calculated output current
value is not the same as the real output current. The real current output is based on the
opposite input resistance and cannot be more than 22 mA.
Data logger
interval Sets the interval at which the shown value is saved to the data logger. Options: OFF
(default), 5 minutes, 10 minutes, 15 minutes, 20 minutes or 30 minutes
4. Complete the settings based on the Function setting.
Linear control function
Option Description
Filter Sets the record time for the recorded measured values. The average of the recorded values
during the record time is shown on the analog output.
Filter unit Sets the time unit for the Filter setting. Options: seconds (default), minutes, hours or days.
Maximum Sets the maximum current value on the analog output. Default: 20 mA
Scale Sets the output current range. Options: 0-20 mA (default) or 4-20 mA
Low value Sets the selected source value shown as 0 mA (0-20 mA) or 4 mA (4–20 mA) on the analog
output. Default: 0
High value Sets the selected source value shown as 20 mA on the analog output. Default: 20
Error mode Sets the controller to not change the analog output value (Hold) or show the transfer value on
the analog output when an internal error occurs. Options: Hold or Transfer
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