omnigrad M TR 44, TR 45
2
Hauser
Areas of application
• Food industry: milk, beer, fruit juice, syrup, chocolate, oils/fats, powders, auxiliary services, storage
tanks/silos, CIP/SIP systems
• Biotechnology industry: fermenters, auxiliary services, CIP/SIP systems
• Pharmaceutical industry: fluids, acids, purified water, auxiliary services, CIP/SIP systems
• Fine chemicals industry: cosmetics, auxiliary services, CIP/SIP systems
Function and system design
Measuring principle
In the Platinum RTD (Resistance Temperature Detector) thermometers the sensing element consists of an elec-
trical resistance with value of 100
Ω
at 0°C (called Pt100, in compliance with standard DIN EN 60751), which
increases at higher temperatures according to a coefficient characteristic of the resistor material (platinum). In
industrial thermometers that comply with the DIN EN 60751 standard, the value of this coefficient is
α
=
3.85*10
-3
°C
-1
, calculated between 0 and 100°C.
Equipment architecture
The Omnigrad M TR 44 and TR 45 temperature
sensors
are made
up
of
a measurement probe, with (TR 45)
or without (TR 44) a protection well, and a housing (head), which may contain a transmitter or the terminals
for the electrical connection.
In TR 45 the probe is a sensing insert, placed inside the thermowell and spring loaded underneath
it, so as to
improve the heat transfer.
As in TR 44, the sensing element (Pt100) is positioned close to the tip of the probe.
The (TR 45) thermowell is obtained from a 9 mm
diameter pipe. The final (sensing) part can be
straight, tapered, i.e.
with its
diameter smoothly
decreased by means of a swaging procedure, or
reduced (stepped).
In the TR 44, the sheath of the probe is developed
from a 8 mm or a 6 mm pipe. In the 8 mm, the final
(sensing) part always has a reduced (stepped) diam-
eter. In the 6 mm, the probe pipe is always straight.
The probe (TR 44) or thermowell (TR 45) can be
installed on the plant (pipe or vessel) by means of a
hygienic process connection, which can be chosen
among the most common types (see "System com-
ponents" section).
Both TR 44 and TR 45 with Varivent
®
process con-
nections, are built to 3-A
®
and EHEDG design cri-
teria, which allow the sensor to withstand any
stress caused by CIP (Cleaning In Place) and SIP
(Sterilization In Place) processes.
The electrical structure of the instruments always
complies with DIN EN 60751 standard rules.
The housing can be of different types and materials
(plastic, painted aluminium, stainless steel).
The way in which it fits to the rest of the probe and
the gland for the cable entry ensures a minimum
grade of IP65 (Ingress Protection).
Fig. 1:
TR 44 (left) and TR 45 (right)
Material
Wetted parts in SS 316L/1.4435.
Weight
From 0.5 to 2.5 kg for standard options.
