
B–63523EN/03
3. INSTALLATION
51
To protect the devices from surge voltages due to lightening, it is
recommended to install surge–absorbing elements between the lines of
the input power and between one line and ground. This does not,
however, assure protection from all surges due to lightening.
The recommended items are as follows. (Items made by Okaya Denki
Sangyo Co.)
For the 200–V system
Between lines R S A S V–781BYZ–2
Between line and ground R S A S V–781BXZ–4
For the 400–V system
Between lines R S A S V–152BYZ–2A
Between line and ground R S A S V–801BXZ–4
The surge–absorbing elements used for measures against surges due to
lightening must be installed in the input power unit as shown in the figure
below. The figure below shows an example in which an insulating
transformer, shown by dotted lines, is not installed. If an insulating
transformer is installed, surge–absorbing element 2 (between line and
ground) is not required.
R
S
T
PE
a
b
AC
input
Insulating
trans-
former
Nonfuse
breaker
Nonfuse
breaker
To CNC
AC
reac-
tor
Servo unit
power
supply
module
M
C
C
5A
Nonfuse
breaker
To other electric parts
on the machine
Surge–absorbing element 1
(between lines)
Surge–absorbing element 2
(between line and ground)
Input
break-
er
3.5.6
Measures Against
Surges due to
Lightning
Installation procedure