12. SAFETY FOR USING AC CONNECTIONS B-61813E/03
12.1 INSTALLATION ENVIRONMENT
12.1.1 Installation Category (Overvoltage Category)
The available impulse surge level to the ground that appears in the
power source is 2.5kV maximum.
(100VAC system power source is needed in AC input module
According to the standard, the available impulse surge level to the
ground is 1.5kV for this power source (voltage of which is 150VAC or
less) However, for this module, the available impulse surge level to the
ground thet apperars in the power source is 2.5 kV.)
Generally, an isolation transformer used for the main power source is
regardrd as an effective surge filter.
The class of the 16-point relay output module (AOR16G) is set to
installation category (overvoltage category) I.
(Keep any impulse voltage to ground that may appear on the AC power
to within 1.5 kV.)
The class for the 8-point relay output module (AOR08G), AC output
module, and AC input module is set to installation category
(overvoltage category) II.
12.1.2 Pollution Degree
Install the unit in the environment of pollution degree 2 or
In cabinet of IP-54 or better (described in 3.1), it can be considered as
pollution degree 2 or better usually. The IP degree required is
dependend on the circumstances of machine tool, so please chooce the
adequate degree in accordance with such environment.