3
ELECTRICAL CONNECTIONS
22
OPTIWAVE X400
www.krohne.com
10/2017 - 4006413501 - AD NEPSI OPTIWAVE x400 R01 en
3.6 Ex d ia / Ex iaD tD equipment
3.6.1 General notes
Ex d ia- and Ex iaD tD-approved equipment have two separate compartments. The electronics in
the electronics block compartment are Ex ia-approved and the terminal compartment is Ex d /
Ex tD-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 (IEC 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 GB 3836.1 and GB 3836.2. 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 and a minimum of 5 threads are engaged in the cable entry.
•
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 GB 3836.1 and GB 3836.2. 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 d ia- and Ex iaD tD-approved equipment
1
Electronics block (Ex ia) compartment
2
Terminal (Ex d / Ex tD) 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 d /
Ex tD terminals.
If you must remove the terminal block for servicing, do not open the terminal compartment in a
potentially explosive atmosphere.
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.
