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MAteRIAL tHeRMoCoUPLe InstALLAtIon
➔ Install a Hauck Rapid Response Material Temperature Thermo-
couple in the material discharge chute to sense the temperature
of the material leaving the dryer.
1" Pipe coupling
(intalled by customer)
DAM
Discharge
chute
Drawing showing the placement of the thermocouple and "dam"
in the dryer discharge chute.
➔ A small clearance (1" maximum) should be provided under the
thermocouple so material will not be trapped between the ther-
mocouple and the chute. Trapped material will cause a heat loss
path and the thermocouple will give erroneous readings.
➔ The thermocouple should make good contact with the material but
not be subject to severe abrasion caused by high velocities. If the
material is moving so fast that it bounces and leaves air adjacent
to the thermocouple, the temperature it senses will be lower than
the material. It may be necessary to place a dam in the chute so
that the thermocouple is in a relatively slow moving area next to
the dam. The dam must only be wide enough and high enough
to create a localized area of build-up where the material loses
velocity BUT DOES NOT STOP FLOWING. The thermocouple
must not be located in a stagnant zone or erroneous temperature
readings will result. Because of the large number of variables
involved, it is impossible to set down any exact size or location
of the dam that will always work. Field experimentation will be
neces¬sary if good results are to be obtained. It is advisable to
tack weld the dam in place so that it can be easily modified if it
fails to perform satisfactorily.
➔ During normal operation, the thermocouple should be rotated
once a month to expose a different area of its surface to the
abrasive forces of the material. This procedure will increase the
effective life of the thermocouple. If excessive wear occurs, a
protective tube may be added to shield the shaft in the region of
the high velocity flow
➔ Thermocouple cables must be separated from AC power and
control wiring to avoid interference and nuisance shutdowns.
Observe polarity when making thermocouple connections. Re-
gardless of TC type, the red wire is always negative.
➔ Wire the thermocouple to the proper terminals in the panel.
Access door
Brass adapter
bushing
Thermocouple
Set-screw
15°
10"
REF
11
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