Analog Output Setup

The 9120 controller has the option of two analog outputs. The outputs are ranged for a 4 – 20 milliamp signal or a 0 – 20 milliamp signal. Each output comes with a factory default configuration dependent on the application. Each output can be modified prior to shipment to your facility or in the field by a supervisor.

 

Analog Output Terminals:

Analog output 1 – terminals 24 and 25

Analog output 2 – terminals 25 and 26

 

Assignment

The analog output assignment can be modified depending on your system requirements. To change the Assignment, first select which analog output you want to change by selecting it in the pull-down menu.  Select the desired assignment from the list and click OK. The following is a list of the options:

 

PV 1 retrans        Input 1 retrans        

Loop 1 inc        Input 2 retrans        

Loop 1 dec        Input 3 retrans        

Loop 1 combo        Not Used        

PV 2 retrans        O2 offset log        

Loop 2 inc        SP1 retrans        

Loop 2 dec        SP2 retrans

Loop 2 combo        SP3 retrans

PV3 retrans        Programmer ID number

Loop 3 inc

Loop 3 dec

Loop 3 combo

    

Combo example for carbon : 4 – 12 mA Air

                      12 – 20 mA Gas

 

Offset

This is the starting point; the Process Variable value at which you get 4 milliamps.  Clicking on this value will display an input box from which the user can select a new value.  The range is –32767 to 32767.

 

Range

This is a Process Variable value between 4 and 20 milliamps.  Clicking on this value will display an input box from which the user can select a new value.  The range is –32767 to 32767.  Note - The range, although not displayed with a decimal point, contains a decimal point that is dependent on the process variable selected.  For example, If the offset is 20 mV for 4 mA, and you want 100 mV to be 20 mA, then your range should be 80.  If the process variable is temperature, then the range will be 80, since temperature PVs do not have a decimal.  If the PV is % Carbon, then the range will need to include the two decimal points for % Carbon.  So, a range of 80 will be entered as 8000.  See below for more examples.

 

Current Selection

Provides the option of 4-20 mA or 0-20 mA control.

 

Offset and Range when assigned to a control loop

Inc -- 0 = 4mA, 100 = 20mA

Dec -- 0 = 4mA, -100 = 20mA

 

Example: if 4 – 20 mA = 800 mV - 1200 mV and PV is Temperature

    Offset  = 800 (starting point)

    Range = 400

 

Example: if 4 – 20 mA = 800 mV - 1200 mV and PV is O2

    Offset  = 800 (starting point)

    Range = 4000 (400.0)

 

Example: if 4 – 20 mA = 800 mV - 1200 mV and PV is % Carbon

    Offset  = 800 (starting point)

    Range = 40000 (400.00)

 

O2 Exponent Range

This menu option will allow the user to set the Oxygen exponent range.  The range is -32767 to 32768.