QIRF Operation And Maintenance Manual
QIRF Operation Manual
May. 01, 2012
85050-301-000 Rev C
11
2.4.6 RS-485 Driver Replacement
RS-485 lines in heavy industrial environments are sometimes subjected to magnetic
disturbances causing sufficient inducted power surges to damage the driver integrated
circuit (IC). This IC U7 has a socket on the circuit card for ease of replacement in the
field.
2.4.7 4-20mA or 2-10VDC Analog Output
QIRF can provide one channel 4-20 milliamp analog outputs or 2-10VDC analog output.
The maximum output impedance is 600 ohms for 4-20mA output. The maximum output
current is 10 mA for 2-10VDC output.
Test point SIG+ and SIG- are used to measure the current online when the QIRF is
working in the field.
The module can also be used to output 2-10VDC if the Jump J5 2-3 is connected. The
default setting: J5 1-2 is connected that mean the output is 4-20mA analog output.
The analog output may be defined in complex ways allowing assignment of different
values to both 4 milliamps and 20 milliamps. You may even assign a gas concentration to
4 mA, which is higher than the concentration assigned to 20 milliamps. The QIRF will
draw a straight line between.
If there is any fault found in QIRF, it will output 2.5mA to indicate the fault.
