Vaisala HMT360 - Manual (Page 38)

User’s Guide ______________________________________________________________________
36 ___________________________________________________________________ M010056EN-J
Installation in Hazardous Locations
US and Canadian Requirements
USA (FM): Wiring for intrinsically safe operation is shown in Appendix
B, Wiring for Intrinsically Safe Operation, FM, on page 91 .
Canada (CSA): Wiring for intrinsically safe operation is shown in
Appendix C, Wiring for Intrinsically Safe Operation, CSA, on page 93 .
European Requirements
CATEGORY 1 (Zone 0)
HMT360 has to be connected to Exia-certified associated apparatus with
galvanic isolation, gas group IIB or IIC.
CATEGORY 2 or 3 (Zone 1 or 2)
HMT360 has to be connected either to a Zener barrier or galvanic isolator
Figure 17 on page 39 and Figure 18 on page 40 present examples of
galvanic isolators and Zener barrier connections (only Ch 1 connected).
NOTE If both analog outputs are in use, the Ch 1 (-) and Ch 2 (-) must be short
circuited (see
Figure 19 on page 41 ).
NOTE If both analog outputs are in use with a galvanic isolator, the Ch 1 (-) and
Ch 2 (-) must be short circuited (see
Figure 19 on page 41 ).