KROHNE OPTIFLEX 4300C ATEX EN - Manual (Page 16)

3
ELECTRICAL CONNECTIONS
16
OPTIFLEX 4300 C
www.krohne.com 02/2009 - 4000523601 - AD ATEX OPTIFLEX 4300 R01 en
3.6.2 How to connect the electrical cables
• Use only flameproof and Ex d-approved cable entries and plugs.
• If you use only one cable entry, seal the other one with an Ex d-approved plug.
• All Ex d-approved installations must agree with European standards EN 60079-1.
Conduit entries
• Connect the device to an Ex d-approved conduit system.
• Install the applicable Ex d-approved sealing device. It must be installed adjacent to the
housing. For further information, refer to European Standard EN 60079-1.
• If you use only one cable entry, seal the other one with an Ex d-approved plug.
Load resistor
• Connect the load resistor to the positive terminal of the power supply
• Ground the negative connection.
• If the load resistor has to be connected to the negative terminal, the loop resistance must not
be more than 250 ohms.
Figure 3-4: Compartments in Ex d [ia]-approved equipment
1 Electronics block (Ex ia) compartment
2 Terminal (Ex d) compartment
INFORMATION!
If you must open the electronics block compartment and remove the electronics blocks for
servicing, it is not necessary to disconnect the wires in the Ex d compartment.
INFORMATION!
The flamepath dimensions are better than the values specified in the European Standard
EN 60079-1 (minimum length 14.5 mm and maximum gap 118 µm).
INFORMATION!
Cable entries are supplied on customer demand. If you supply the cable entries, this part must
have a degree of ingress protection IP≥6x (EN 60529).
CAUTION!
Do not ground the positive connection.
AD_ATEX_OPTIFLEX4300_en_090528_4000523601_R01_D5D.book Page 16 Thursday, May 28, 2009 6:00 PM