This tester is provided with a protective resistor (10 Ω) for prevention of
accidental short circuit in measuring power voltage, and has a 1 A Fuse
(500 V AC,With a Interrupting rating of 50 kA) connected in series from
the terminal (refer to figure.)
If a short circuit occurs in the tester circuit, the protective resistor holds
down the short circuit with the fuse.
As the protective resistor keeps excessive short circuit current from
running, the arc at the tip etc. of the test bar can be held down to the
minimum for greater safety.