5-16
TOS9213S/ TOS9213AS
■
GUARD
•
If it is not kno
w
n
w
hether the DUT or jig is gro
u
nded, ne
v
er select GUARD.
If GUARD is selected
w
hile the DUT is gro
u
nded, the ammeter
w
ill
b
e
short-circ
u
ited, there
b
y disa
b
ling meas
u
rement and posing a gra
v
e dan-
ger. See Fig. 5-4 (B).
• If GUARD is selected, do not connect this tester to any meas
u
ring instr
u
-
ments or other de
v
ices that in
v
ol
v
e single-side gro
u
nding, s
u
ch as Kik
u
-
s
u
i’s high-
v
oltage digital
v
oltmeter 149-10A and c
u
rrent cali
b
rator
TOS1200. Other
w
ise, the ammeter
w
ill
b
e short-circ
u
(A) Connecting the 149-10A
(B) Selecting GUARD
w
hen the DUT is gro
u
nded
Fig.5-4
Dangero
u
s connection
•
If the LO
W
terminal of this tester is connected to the HIGH or LO
W
termi-
nal of the earth contin
u
ity tester TOS6200, the ammeter
w
ill make mea-
s
u
rement errors if GUARD is selected, as the resistor inside the TOS6200
is connected in parallel to the tester’s ammeter. Therefore, to
u
se the
TOS6200, a
v
oid connecting these terminals, or select LO
W
.
WARNING
Setting to GUARD
Ammeter
TOS9213S
TOS9213AS
149-10A
HIGH VOLTAGE terminal
LOW
terminal
D
U
T
Insulation
resistance of
the test lead
wire and jigs
Setting to GUARD
Ammeter
TOS9213S
TOS9213AS
HIGH VOLTAGE terminal
LOW
terminal
D
U
T
CAUTION
