Pfaudler TW Series - 5.2 Construction of the T probe

Tubular probes equipped with T probes
can optionally be combined with the
following measuring probes made by
Pfaudler:
n Typ P Measuring probe for glass
monitoring
n Typ FT Measuring probe for capaci-
tive detection of filling limits
or interfaces between liquids
n Typ FS Measuring probe continuous,
capacitive detection of filling
levels
n Typ TW Measuring probe for tem-
perature measurement us-
ing a resistance thermometer
For more details about possible com-
binations, please contact the Pfaudler
Instrumentation department.
5.2.3 Ring probe
The thermocouple of ring probes con-
sists of very thin, narrow bands made of
the pallaplat material combination. The
pallaplat bands are fused into the glass
layer.
The measuring location is in the middle
of the cylindrical inside area. Ring probes
can be produced with a maximum of 4
measuring locations.
In order to provide electrical connec-
tion to the thermocouples, the pallaplat
bands fused into the glass are routed
close to the terminal box and connected
to the compensating line. In turn, the
compensating line is introduced into the
terminal box where it is connected to the
transmitter.
Ring probes equipped with T probes can
optionally be combined with the following
measuring probes made by Pfaudler:
n Typ P Measuring probe for glass
monitoring
n Typ FT Measuring probe for capaci-
tive detection of filling limits
or interfaces between liquids
For more details about possible com-
binations, please contact the Pfaudler
Instrumentation department.
5.2.4 Valve shaft
The measuring location of a probe
mounted on a valve shaft is in the mid-
dle of the valve shaft on the product side.
Power supply to the thermocouple is by
means of pallaplat wires that are insu-
lated and routed through the inside bore
of the valve shaft. The wire ends are con-
nected to the compensating line which in
turn is introduced into the terminal box
where it is connected to the transmitter
type TTH300 (or terminals).
With nominal sizes DN 80/50 or more,
the T probe can be installed in a valve
shaft. A maximum of 2 T measuring loca-
tions are possible. Optionally, a T probe
can be combined with the a measuring
probe Type P (for glass monitoring). For
more details about this possible com-
bination, please contact the Pfaudler
Instrumentation department.
5.2 Construction of the T probe
5.2.1 Probe carrier
The T probe can be installed in various
probe carriers:
n Baffles, thermometer well, Quatro-
Pipe and C baffle (the term tubular
probe will be used below for this type
of probe carriers)
n Ring
probe
n Valve shaft of outlet valves
5.2.2 Tubular probe
The thermocouple of tubular probes con-
sists of very thin, narrow bands made of
the pallaplat material combination. The
pallaplat bands are fused into the glass
layer.
The measuring location, where the two
pallaplat bands are in contact is normally
at the end of the tube in order to mea-
sure the product temperature even at
low liquid levels inside the reactor. When
using tubular probes, several measuring
locations may be fitted at the same or at
different levels. The maximum possible
number of measuring locations depends
on the size of the tubular probe. For
more details, please contact the Pfaudler
Instrumentation department.
In order to provide electrical connection
to the thermocouple, the pallaplat bands
fused into the glass are routed close to
the terminal box and connected to the
compensating line. In turn, the compen-
sating line is introduced into the terminal
box where it is connected to the trans-
mitter.
© Pfaudler GmbH · OI 302-8 e
5
Temperature probes type T/TW
© Pfaudler GmbH 5
Temperature probes type T/TW