Samson 3730-2 Mounting And Operating Instructions page 57

Clause 12.2.2.7 applies when running multi-
core cables and wires with more than one
intrinsically safe circuit.
The radial thickness of the insulation of a
conductor for common insulating materials
(e.g. polyethylene) must not be smaller than
0.2 mm. The diameter of an individual wire
in a fine-stranded conductor must not be
smaller than 0.1 mm. Protect the conductor
ends against splicing, e.g. by using wire-end
ferrules. When two separate cables or wires
are used for connection, an additional cable
gland can be installed. Seal cable entries left
unused with plugs. Fit equipment used in
ambient temperatures below –20 °C with
metal cable entries.
Equipment for use in zone 2/zone 22
In equipment operated according to type of
protection Ex nA II (non-sparking equipment)
according to EN 60079-15:2003, circuits
may be connected, interrupted or switched
while energized only during installation,
maintenance or repair.
Equipment connected to energy-limited cir-
cuits with type of protection Ex nL (en-
ergy-limited equipment) according to
EN 60079-15:2003 may be switched under
normal operating conditions.
The maximum permissible values specified
in the statement of conformity and its ad-
denda apply when interconnecting the
equipment with energy-limited circuits in
type of protection Ex nL IIC.
Cable entry
Cable entry with M20 x 1.5 cable gland, 6
to 12 mm clamping range.
EB 8384-2 EN
There is a second M20 x 1.5 threaded hole
in the housing that can be used for addition-
al connection, when required. The screw ter-
minals are designed for wire cross-sections
of 0.2 to 2.5 mm². Tighten the screws by 0.5
to 0.6 Nm.
The wires for the set point must be connected
to the terminals 11 and 12 located in the
housing.
Only use a current source. OVERLOAD ap-
pears on the display when the set point ex-
ceeds 22 mA.
NOTICE
!
The connection of a voltage source (U ≥ 7 V
or U ≥ 2 V when connected to the wrong
pole) can damage the positioner.
Only use a current source and never a volt-
age source!
In general, it is not necessary to connect the
positioner to a bonding conductor. Should
this be required, however, this conductor can
be connected inside the device.
Depending on the version, the positioner is
equipped with inductive limit switches and/
or a solenoid valve.
The position transmitter is operated on a
two-wire circuit.
The usual supply voltage is 24 V DC. Taking
the resistance of the supply leads into ac-
count, the voltage at the position transmitter
terminals can be between at least 12 and
30 V DC at the maximum.
Refer to Fig. 20 or to the label on the termi-
nal block.
Connections
57