3. Explosion Protection Instrumentation in Zone 2/Division 2
3-15
TI 33Q01J30-01E
Device Installation
• Devices must be installed by professionally trained personnel.
• Install devices according to NEC (National Electrical Code: ANSI/NFPA-70).
• When devices are installed in a hazardous area in Class I, Division2, put them in a metal
cabinet with a key compliant with FM class 3810 and FM class 3600, or the one approved
by FM or a local testing institution.
When the devices to be connected to field devices in a hazardous area are installed in non-
hazardous area, put them in a metal cabinet conforming to FM class 3810. (*1)
• Instructions provided in GS (General specifications), TI (Technical Information of Installation
Guidance) and/or IM (User’s Manuals) shall be observed.
• Precautions on device use
• Cabinet door must be closed when devices are used.
• Empty slots in a cabinet must be covered by a dedicated cover.
• Each cable in a cabinet must be fixed.
• A breaker to cut power supply must be installed in non-hazardous area so that power
supply to the devices is cut under abnormal circumstances.
• As for the precautions of N-IO field enclosure, refer to Appendix 1.4 CSA NI/FM NI/IECEx
Ex “ec” Control Drawing of N-IO field enclosure.
*1:
Excluding N-IO field enclosure.
Maintenance
• Devices must be installed by professionally trained personnel or ask Yokogawa’s service
office. If devices are installed by person other than those above, FM NI approved products
will be invalid.
• Do not perform maintenance on running devices installed in a hazardous area in Class I,
Division 2.
Disconnect modules and terminals installed in a hazardous area in Class I, Division 2 only
for installation or maintenance.
• Initial and regular maintenance are also done by professionally trained personnel according
to IEC 60079-17.
Wiring
• Devices must be wired by professionally trained personnel.
• Install explosion-proof wiring defined in NEC (National Electrical Code: ANSI/NFPA-70) or
the code in the relevant country to wire devices with no indication of electrical parameters.
Wiring the devices that indicate electrical parameters with the compliant devices can be a
general wiring defined in the relevant country.
Dec. 3, 2021-00
