Specifications

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Siemens FI 01 · 2015 US Edition
Temperature Measurement
SITRANS TS500
Technical description
2
Temperature influence
At the connection head TS500
1)
1)
Notice manual at Ex-applications, please
Influence of extension
The illustration below assists you in selecting the right T length for the neck tube. In this case, the following applies: Connection head
temperature = Ambient temperature + Overtemperature. The temperature in the connection head can thus be assessed as follows:
Extension length X, effect on temperature, dimensions in mm (inch)
Please note that guidance values may change due to local con-
ditions. Please consider these potential changes particularly
with respect to explosion protection.
Also note that the accuracy of the transmitter also depends on
the temperature in the connection head.
Process connection/Thermowell
When selecting a process connection, the process parameters
sometimes only allow a specific technology. In addition, regional
standard-related and customer-specific requirements must be
abserved. The range of products therefore includes a broad se-
lection of standard connections.
In the case of redesigned or newly designed facilities, it is pos-
sible to achieve cost savings by implementing various mea-
sures:
• Use of standard lengths through clever selection of screw,
weld or flange sockets
• Moveable compression fittings
The temperature resistance of a material for process connec-
tions and thermowells also limits the application area of the tem-
perature sensor. The temperature range indicated on the type
plate always refers to the measuring insert, not the material
which comes into contact with media. Two aspects must be con-
sidered when assessing temperature stability:
• What maximum temperature may the material reach without a
load?
• What is the behavior under load?
Process load
Because of the large variety of possible applications and vari-
ables, it is not possible to make general binding statements re-
garding the resilience of components which comes into contact
with media. The load diagrams below can be used for common
applications. However, where operating conditions vary signifi-
cantly, please contact our technical support team.
Load on the thermowell and remedies:
Without transmitter
[°C (°F)]
With transmitter
[°C (°F)]
Aluminum or stainless
steel
-40 ... +100
(-40 ... +212)
-40 ... +85
(-40 ... +185)
Plastic -40 ... +85
(-40 ... +185)
-40 ... +85
(-40 ... +185)
Overtemperature in head B
Process temperature
X = 20 (0.79) (Type 2N)
60
°C (°F)
0
150 (302) 300 (572) 450 (842) 600 (1112) 750 (1382)
X = 40 (1.57)
X = 80 (3.15)
X = 120 (4.72)
X = 165 (6.50)
°C (°F)
(140)
50
(122)
40
(104)
20
(68)
10
Über-
30
(86)
The process itself Correction options
Temperature
Material selection
Pressure
Thermowell type
Flow velocity
Insertion length, thermowell type
Viscosity Insertion length, thermowell type
Vibration Support against vibration
Corrosiveness
Material selection, coating
Abrasion (e.g. carbon dust) Sensing rod, coating
© Siemens AG 2015