National Instruments C Series Getting Started Manual page 4

Caution
install a protection device between the external power
supply and the Vsup pin. The device must prevent the
Vsup-to-COM voltage from exceeding 50 V if there is
a transient overvoltage condition.
Special Conditions for Hazardous Locations Use in
Europe and Internationally
The NI 9467 has been evaluated as Ex nA IIC T4 Gc equipment
under DEMKO Certificate No. 07 ATEX 0626664X and is
IECEx UL 14.0089X certified. Each NI 9467 is marked
and is suitable for use in Zone 2 hazardous locations, in ambient
temperatures of -40 °C ≤ Ta ≤ 70 °C. If you are using the NI 9467
in Gas Group IIC hazardous locations, you must use the device in
an NI chassis that has been evaluated as Ex nC IIC T4, Ex IIC
T4, Ex nA IIC T4, or Ex nL IIC T4 equipment.
Caution
disturbances do not exceed 140% of the rated voltage.
Caution
not more than Pollution Degree 2, as defined in
IEC 60664-1.
4 | ni.com | NI 9467 Getting Started Guide
For Division 2 and Zone 2 applications,
You must make sure that transient
The system shall only be used in an area of
II 3G