Interrupt Priority; Setting The Line Frequency Reference; Checking The Line Frequency Reference - Agilent Technologies Agilent E1412A User Manual

Interrupt Priority

Setting the Line Frequency Reference

Checking the Line
Frequency
Reference
Chapter 1
The E1412A Multimeter is a VXIbus interrupter. However, there is no
interrupt priority level setting to be made on the module. Interrupt priority
level, setup, and activation are configured on the resource manager which is
the interface to the VXIbus and contains any instrument drivers required to
communicate with a VXI module. Your resource manager could be a VXI
command module, embedded PC controller, the PC-based VXLink Interface
(ISA-to-VXI), the Series 700 workstation VXI-MXIbus interface or another
VXI controller. To configure the interrupt priority on the E1405B and
E1406A Command Modules, you would use the
command subsystem. Refer to your resource manager's documentation for
information on setting the system's interrupt priority.
You must set the line frequency reference to the line frequency of the power
source to your mainframe for maximum normal mode rejection (NMR).
NMR is the multimeter's ability to reject power line frequency noise in a DC
voltage or ohms measurement. You should set the multimeter's line
frequency reference to the exact power line frequency (50, 60 or 400Hz).
Failure to set the line frequency reference to that of your source will cause
reading errors.
You use the
CALibration:LFRequency
reference. The default setting at power-on is 60Hz. If you use 50Hz or
400Hz you need to set the line frequency reference for maximum NMR.
Specifying 400Hz actually sets the line frequency reference to 50Hz since
50Hz is a sub harmonic of 400Hz. Executing a
will return +50 after executing
reference to 400Hz.
The line frequency reference setting is also useful when the device being
measured operates at a different frequency than the multimeter. For
example, if the multimeter has a power line frequency reference of 60Hz and
the device being measured has a power line frequency of 50Hz, maximum
NMR is achieved by setting the multimeter's reference frequency to 50Hz
by executing:
CAL:LFR 50
The CALibration:LFRequency?
power line frequency reference. The command returns +50 or +60. For a
setting of 400Hz, +50 is returned since 50Hz is a sub harmonic of 400Hz.
command to set the line frequency
CALibration:LFRequency?
CAL:LFR 400 to set the line frequency
command returns the present setting of the
Agilent E1412A Multimeter Module Setup
DIAGnostic:INTerrupt
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