Line And Loop Residual Impedance - Fluke Calibration 5322A Operator's Manual

5322A
Operators Manual
While connected to the DUT, the Product monitors the voltage and current
appearing across the resistance. The actual current flowing in the resistance is
displayed in the PARAMETERS area of the display with the hold feature. The
measured current value can be reset with the Clear softkey. In addition to actual
current, the polarity of the test signal generated by the DUT, the Prospective
Fault Current (PFC), and the mode of residual impedance correction are shown
in the PARAMETERS area of the display.
The type and polarity of the DUT signal is identified as fullwave ( or ),
positive pulse () or negative pulse (). The prospective fault current is
computed by measuring the actual ac voltage on the output terminals, and then
multiplying it by the residual resistance calibration value.
The displayed resistance value appears at the Product OUTPUT HI
and LO terminals. The calibration value includes resistance of test
leads specified in the parameter Series resistance.
With the output connected, adjust the resistance value using the rotary knob or
numeric keypad. Any new values set through the front panel take approximately
500 ms to appear on the output terminals. If the set value should exceed the
upper range limit or lower range limit, the Product displays Value too Large or
Value too Small, respectively.

Line and Loop Residual Impedance

While calibrating loop and line impedance functions, the Product uses its ac line
power circuit as part of the measurement. The impedance of this branch circuit
can cause a significant amount of undetermined impedance in calibration.
Therefore, it is important to ensure the mains circuit of the Product has the lowest
possible impedance.
Residual impedance is that impedance sensed at the power input socket of the
Product. Residual line impedance is the impedance found between the line (L)
and neutral (N) wires.
The actual residual impedance of the Product and the power circuit
to which it is connected is used in the calibration process for the loop
and line impedance calibration. Therefore, this impedance sets the
lowest impedance value and becomes the calibration zero point for
DUTs.
To ensure the best quality and stability of calibration:
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Use only the power cord supplied with the Product.
Ensure the power outlet makes good contact with the Product power cord.
Have qualified service personnel ensure the branch circuit wire connections
to the power outlet are tight and the lowest contact resistance possible.
Never use extension cords or power strips to power the Product.
Because residual impedance can be affected by other electrical devices
attached to the same branch circuit as the Product, move these devices to
other circuits.
Note
Note