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.