User guide

ELECTRICAL CONNECTIONS 3
15
OPTIFLEX 4300 C
www.krohne.com02/2009 - 4000523601 - AD ATEX OPTIFLEX 4300 R01 en
3.5.4 Electrical schema
3.6 Ex d [ia] equipment
3.6.1 General notes
Ex d [ia]-approved equipment have two separate compartments. The electronics in the
electronics block compartment are Ex ia-approved and the terminals compartment is Ex d-
approved.
Without an external sensor
Figure 3-2: Electrical schema for Ex i-approved equipment without an external sensor
1 Intrinsically-safe power supply (use second power supply for optional terminal 2)
2 Non-Ex zone
3 Ex zone
4 Resistor for HART
®
communication
With an external sensor
Figure 3-3: Electrical schema for Ex i-approved equipment with an external sensor
1 Intrinsically-safe power supply (use second power supply for optional terminal 2)
2 Non-Ex zone
3 Ex zone
4 Resistor for HART
®
communication
5 External sensor
=
=
Ex i
HART
1
1
2
4
5
3
AD_ATEX_OPTIFLEX4300_en_090528_4000523601_R01_D5D.book Page 15 Thursday, May 28, 2009 6:00 PM