NF KP3000GS, Instruction Manual

Page: 236 / 279

8.2 When a Failure is Suspected
KP3000GS 217
Table 8-3 Actions When a Failure is Suspected (Continued)
Category Symptom Possible Cause Necessary Actions
Problem of
USB
memory Files in the USB
memory do not
appear on the
screen. USB eject operation was
performed. Perform the USB eject operation
(

4.9 ) again just in case, and
remove the USB memory.
Reconnect the USB memory and
make sure the file names are
displayed.
One folder contains over
500 files. Reduce the number of files in a
folder to 500 or less.
The format is illegal. Use a FAT32-formatted USB
memory.
Problem at
driving an
inductive
load (e.g.,
transformer) The current
waveform is
abnormal (e.g.,
asymmetrical or
excessive) when
the transformer
is connected as
the load and the
AC voltage is
output. The output offset
voltage (DC component)
caused the load
transformer core to
reach the magnetic
saturation. In the AC mode, the control
function works to eliminate the
offset voltage (DC component).
When the product is used in the
ACDC mode, switch it to the AC
mode.

3.4.1
If it does not bring much
improvement, adjust the DC
offset.

4.14
The output
overvoltage error
occurs for an
inductive load
(e.g.,
transformer). An abrupt change in the
output current generated
a back electromotive
force. When the output is off or the peak
current limiter is activated, the
load current may change abruptly,
which generates a back
electromotive force to cause the
output overvoltage error. To avoid
the abrupt current change, reduce
the setting value of the peak
current limiter sufficiently for a
smaller output current, or
conversely set it to a sufficiently
large value to disable the limiter
to be activated, or sufficiently
reduce the amplitude before
turning off the output.

4.1.1
Memory
function-
related
problem The memory
cannot be
recalled. The output is on. The output on state does not allow
the recall. Turn the output off.