Pfaudler TW Series - 6.5 Installation of the TW probe; 6.6 Connection of the TW probe

6
+5
MT_05_0004_1d TW-Sonde.fh11
m When using your own reduc-
ing flanges, please make sure that
the element covering the contact
area below the terminal box does
not sit on the reducing flange (cf.
Fig. 2). In the event of non-compli-
ance, the glass may be damaged at
the bottom side of the flange, and
the fused-in metal strips may be
interrupted.
6.6 Connection of the TW probe
The following information only applies
to TW probes in connection with the
transmitter.
A supply unit with the following specifica-
tions is necessary for power supply:
n Supply current: I
S
= 0 - 20 mA
n Supply voltage: U
S
= 8,5 ... 30 V DC
n in potentially explosive
atmospheres: U
i
= 8,5 ... 29,4 V DC
For applications in potentially explosive
atmospheres, supply units in intrinsically
safe design must be used.
The power supply unit must be installed
outside the potentially explosive area.
The installation instructions of the manu-
facturer are mandatory in this respect.
The connection between the power sup-
ply unit and the transmitter can be made
using standard signal cables.
The probe carriers must be grounded
using copper or stainless steel wires with
a minimum conductor area of 10 mm
2
.
The electrical connection is made in
compliance with the connection diagram
shown in Fig. 4.
6.5 Installation of the TW probe
As already mentioned, the TW probe can
be installed in the following probe car-
riers: Paddle-type baffles, thermometer
wells, Quatro Pipe These probe carriers
are generally also referred to as tubular
probes.
Before installing a tubular probe in a
reactor or a pipeline, you should verify
whether there is sufficient distance to
the agitator and the reactor or pipeline
wall. If necessary, suitable spacers or
reducing flanges must be used.
Assembly process:
t Place flange gasket on nozzle.
t Protect the nozzle and the probe
against damage by inserting a piece
of cloth or a PTFE sleeve into the noz-
zle. Slowly introduce the tubular probe
into the reactor through the nozzle.
Avoid pendulum motion.
t Tighten flange screws evenly cross-
wise with the prescribed tightening
torque; (cf. Tab. 3).
white
red
1
4
green
black
2
3
power supply unit with electrical
isolation Ex ia/ib
max. 30 V DC 100 mA
current output
4 - 20 m A
power supply 24 V DC/AC
(230 V AC)
-
MT_05_0004_1e
Fig. 4 Connection diagram of the TW probe
TW-Sonde
Pt
100
}
optional floating
change-over
contacts
Temperature probes type T/TW
© Pfaudler GmbH · OI 302-8 e
14
© Pfaudler GmbH 14
Temperature probes type T/TW