KROHNE BM 70 M - Manual (Page 96)

10 BM 70M-EEx/ BM 70Mi-EEx
5 Assembly and installation
Assembly and installation to be carried out in accordance with the valid installation standards for
hazardous areas (e.g. EN 60079-14) by specialist personnel who have received training in
explosion protection.
In this connection, take note of the directions given in the standard Installation and Operating
Instructions, these Supplementary Installation and Operating Instructions (Ex), and the EC type
test certificate.
Verify the suitability of the level gauge by comparing the data given on the nameplate with that
given in Section 3.2.1 (Categories / Zone allocation), Section 2 (Type code) and 4 (Marking).
Attention is drawn in particular to the following points.
5.1 Flange systems
5.1.1 Flange system V96 / SA (optionally with sensor connection)
Install appropriately so as to avoid mechanical loads and sparking caused by blows to the
antenna and extensions (e.g. by agitators).
5.1.2 Flange system V96 with heating (optionally with sensor connection)
The operator shall ensure that the temperature of the heating medium, when used in Zone 0,
does not exceed 80% of the ignition temperature (in °C) of the products in the tank, and does
not exceed the maximum allowable flange temperature as a function of the temperature class.
The pressure of the heating medium should not exceed 6 bar. In addition, when operating the
heating system, make sure that inlet and outlet are correctly connected (see information labels
on flange).
5.1.3 Flange system V96 / SA with purging system and/or sensor connection
The locking screw for the purging system and/or for the sensor connection forms, together with
the screw thread of the tank mounting flange, a flameproof joint when given at least five full
turns. The quality grade of the thread of the inserted screw is “medium” in accordance with DIN
13 and ISO 965.
This screw must be removed before the purge/sensor connection can be used. But do not
remove the locking screw for the purge/sensor connection unless the tank is in non-pressurized
condition!
Take appropriate measures to ensure that the purge/sensor connection is fitted with a flame
trap. Together with the thread of the tank mounting flange, the connection screwed into that
flange must form a flameproof joint in conformity with EN 50 018 (note thread quality grade and
threaded length).
The choice of a suitable purging medium and operation of the purge/sensor connection are the
responsibility of the operator.
When the purge/sensor connection is used, the operator shall ensure that no unpermissible
changes are made to process conditions (e.g. temperature, pressure, etc.).
5.1.4 Flange system V96 with heating and purging systems
Refer to the information and directions given in sections 5.1.1 and 5.1.2.
5.2 Electrical connection BM 70 M-EEx
5.2.1 Terminal compartment
The electrical connection for power and I/O functions is made in the terminal compartment of the
signal converter. The terminal compartment may, as described in Section 2 (Type code) and
Section 3 (Main safety-relevant characteristics), optionally be designed in types of protection
EEx e, EEx d, EEx ei and EEx di: