Samson 3738-20, Mounting And Operating Instructions

Page: 33 / 84

EB 8390 EN 33
Connections
ing plug must be the same as that of
the limit switch.
Do not loosen enameled screws in or
on the housing.
Note on the selection of cables and
wires:
−
Observe clause 11.2 for installa-
tion of the non-intrinsically safe
circuits and c lause 12 of
EN 60079-14 (VDE 0165,
Part 1) for installation of the in-
trinsically safe circuits.
Clause 12.2.2.7 of EN 60079-
14 applies when running multi-
core cables and wires with
more than one intrinsically safe
circuit.
−
The radial thickness of the insula-
tion of a conductor for common
insulating materials (e.g. polyeth -
ylene) must not be smaller than
0.2 mm. The diameter of individ -
ual wires in a fine-stranded con -
ductor must not be smaller than
0.1 mm. Protect the conductor
ends against splicing, e.g. by us
-
ing wire-end ferrules.
−
When two separate cables are
used for connection, an addition-
al cable gland can be installed.
−
Seal cable entries left unused with
certified Ex e blanking plugs.
The electronic limit switch is powered over
the connection of the contact A according to
DIN EN 60947-5-6. An additional electrical
power supply is not required.
The following function and terminal labeling
apply to the contacts A and B:
Connection
Position + –
Contact A 41 42 Fail-safe position
(0 %)
Contact B 51 52 Operating position
(100 %)
Cable entry
The threaded connection for the terminal
compartment is designed with an M20 x 1.5
thread.
The screw terminals are designed for wire
cross-sections of 0.2 to 1.5 mm². Tighten by
at least 0.5 Nm.
NOTICE
− The switching voltage of the inte-
grated solenoid valve is connected
either at the terminals V1 (81/82)
or at the terminals V3 (81/82)
(Type 3738-20-xxx1400xxx000).
Only connect one pair
of 81/82 terminals.
− Do not connect the switching volt -
age to the contacts A-St. Other -
wise, the device will be damaged.