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Explosion-proof telephone connecting relay mTCR
1
Description
The telephone connecting relay type
mTCR is used as a fixed device in
areas that may be at risk due to
explosive gas or dust atmospheres
and which require devices of device
groups II and III of the categories
2G and 2D.
The designated position of normal
use is not mandatory.
The telephone connecting relay type
mTCR is implemented in the follo-
wing ignition protection classes:
Ex e ib mb IIC T4 Gb
Ex tb IIIC T1 35°C Db
IP66
Temperature range
-40°C Ta +70°C
The telephone connecting relay type
mTCR is intended for connection to
analogue telephone networks. It
can be simply installed parallel to a
telephone.
The telephone connecting relay
serves for call signalling through
providing potential-free switching
contacts for the connection of
signalling devices. This means for
example that up to two external
devices (e.g. a horn and a flash
light) can be switched on via call
signal. The call break bypass can
be individually adjusted for one of
the connected devices.
The installation regulations in
accordance with IEC/EN 60079-1 4
as well as the respective national
installation regulations must always
be taken into consideration.
Device strutcture
The telephone connecting relay type
mTCR has an unpainted housing
made of electrostatically conductive
compressed material.
The housing consists of a box-
shaped lower part for receiving the
electronics module. The electronics
module is firmly cast into the lower
part of the housing and cannot be
exchanged.
The cover is pressed onto the lower
part of the housing using four
screws, with a circumferential seal
positioned in between. This forms
the non-intrinsically-safe connection
compartment.
Intrinsically safe DIP switches
An intrinsically safe 4-pole sliding
switch extends out from the casting
within the device (see device over-
view) for pre-setting the desired
mode of operation.
Designation
Type
Article no.
Order data
Telephone connecting relay
mTCR
410 100 100
mTCR
mTCR 3.1_E