Hioki ST5540, Instruction Manual, Page: 132 / 326

7.7 Power On Polarity Switching (to keep equipment under test on during polarity
126
1.
Turn off the instrument and set the breaker to Off ( ).
2.
Connect the power cord to the secondary side of the isolation transformer.
(Do not connect the neutral wire to ground when an isolation transformer is used.)
3.
Connect the secondary side of the isolation transformer to [LINE IN] on the HiTESTER.
4.
Connect the equipment under test to the terminal block on the front panel of the HiTESTER.
5.
Connect the primary side of the isolation transformer to a commercial power supply.
6.
Turn on the instrument and set the breaker to On ( ).
7.
Set the instrument breaker to On.
7.7 Power On Polarity Switching
(to keep equipment under test on during
polarity switching)
• When the power on polarity switching function is used, be sure not to
connect the neutral wire on the secondary side of the isolation trans-
former to ground.
• When using an isolation transformer, be sure not to make any connec-
tions to the primary side before making connections to the secondary
side. Otherwise, an electrical shock could result as voltage is output
from the secondary side in some configurations.
Power on polarity switching requires use of an isolation transformer. An error will
be generated and measurements cannot start if an isolation transformer is not
connected.
Connect the isolation transformer
2
3
4
5
Primary side
Secondary side
6
7
[LINE IN]
L
N
E
Connection example