ELECTRICAL CONNECTIONS
3
21
OPTIWAVE X500
www.krohne.com
06/2017 - 4005809801 - AD ATEX OPTIWAVE x500 R01 en
3.6 Ex db ia / Ex ia tb equipment
3.6.1 General notes
Ex db ia- and Ex ia tb-approved equipment have two separate compartments. The electronics in
the electronics block compartment are Ex ia-approved and the terminal compartment is Ex db /
Ex tb-approved.
3.6.2 How to connect the electrical cables
Cable glands are supplied on customer demand. If you supply the cable glands, this part must
have a degree of ingress protection IP
≥
6X (EN 60529). We recommend that you use a part that
has a degree of ingress protection IP
≥
68. Make sure that the cable gland is sealed.
Terminal compartment
•
If you connect electrical wires to the terminals in the flameproof terminal compartment, use
approved flameproof cable glands (M20×1.5 or
½
NPT). The cable glands must have a test
certificate that agrees with EN 60079-1. Obey the instructions given on the test certificates.
Make sure that that the tightening capacity of the cable gland is applicable to the diameter of
the electrical wire.
•
If you use conduits to connect electrical wires to the terminals in the flameproof terminal
compartment, obey the instructions that follow. Make sure that the conduits are correctly
attached and the flameproof compartment is sealed. The flameproof joint must have a
minimum thread length of 8 mm / 0.32
¨
. The conduits must have a test certificate that agrees
with EN 60079-1. Use conduit stopping boxes that agree with precautions given in the test
certificate and data in standards related to the installation of the conduit.
Figure 3-3: Compartments in Ex db ia- and Ex ia tb-approved equipment
1
Electronics block (Ex ia) compartment
2
Terminal (Ex db / Ex tb) compartment
DANGER!
If you must open the electronics block compartment to remove the electronics blocks for
servicing, de-energize the device. It is not necessary to disconnect the wires from the Ex db /
Ex tb terminals.
If you must open the terminal compartment to remove the terminal block for servicing, de-
energize the device first.
WARNING!
Use only Ex d-approved cable glands and adaptors for Ex d applications. Use only Ex t-approved
cable glands and adaptors for Ex t applications.
