Samson Series 3730 Mounting And Operating Instructions page 46

Connections
In particular, the radial thickness of the con-
ductor insulation for common insulation ma-
terials, such as polyethylene, must have a
minimum radial thickness of 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 fer-
rules.
When two separate cables are used for con-
nection, an additional cable gland can be
installed.
Seal cable entries left unused with plugs.
Devices used at ambient temperatures be-
low –20 °C must be fitted with metal cable
glands.
Equipment for use in zone 2/zone 22
In equipment operated with type of protec-
tion Ex nA II (non-sparking equipment) ac-
cording to EN 60097-15: 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 60097-15: 2003 may be switched un-
der normal operating conditions.
The maximum permissible values specified
in the Statement of Conformity or its ad-
denda apply when interconnecting the
equipment with energy-limited circuits in
type of protection Ex nL IIC.
46
EB 8384-2 EN
Cable entries
The cable entry with M20 x 1.5 cable gland,
6 to 12 mm clamping range.
There is a second M20 x 1.5 threaded bore
in the housing that can be used for addi-
tional connection, when required.
The screw terminals are designed for wire
cross-sections of 0.2 to 2.5 mm². Tighten by
at least 0.5 Nm.
The wires for the reference variable must be
connected to the terminals 11 and 12 lo-
cated in the housing. Only use a current
source!
If the reference variable exceeds 22 mA,
OVERLOAD appears on the LC display to
warn the user.
NOTICE
The wrong connection of a voltage source of
just around 7 V (or around 2 V when
connected to the wrong pole) by mistake can
damage the positioner.
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. Considering the resistance of the
supply leads, the voltage at the position
transmitter terminals can be between 12 V
and 30 V DC.
Refer to Fig. 18 or the label on the terminal
strip for terminal assignment.