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Application Notes for Extreme Temperatures

High Temp Fiberoptics: For Exposure To 482°C

Cryogenics: Cryogenic Imaging System

Cryogenic Turbo Pump

Extreme Temperatures

Philtec sensors can be designed for use in extreme high or low temperatures.

Temperature Limits [Datasheet PDF]

Standard Glass Fiber Sensor Tips

Standard sensor tips are constructed with glass fibers, epoxy and stainless steel housings. These standard materials allow operation down to cryogenic temperatures approaching absolute zero. The upper temperature limits are:

200°C continuous
300°C intermittent
Standard, most models

250°C continuous
350°C intermittent

High Temperature Cure, specify Option T8
400°C continuous
480°C intermittent
High Temperature Construction, Specify Option T9

Fiberoptic Cables

The sensor cables are comprised of glass fiberoptics with a protective sheathing. The sheathing
materials limit the temperature range of the cables as given in the table below. In the most extreme
conditions, the glass fibers can be exposed to cryogenic temperatures near absolute zero and elevated temperatures above 300°C (up to 480°C). Fibers exposed to temperatures above 300°C will become very brittle, and therefore, they should not be flexed during or after such exposure. Fibers can be slowly exposed to cryogenic temperatures and returned to room temperature (avoiding thermal shock) without suffering embrittlement. The temperature limits of the various protective sheathing layers are as follows:

Standard PVC over steel monocoil. Good general purpose sheathing. +10 to +107°C
C1 Stainless steel interlocking hose. Provides maximum strength. -270° to +850°C
C2 Silicone coated fiberglass. very flexible, radiation resistant, no crush resistance.
-62 to +200°C
C3 Silicone over PTFE spiral wrap. Non-metallic light crush resistance,
for short lengths only, 2 meters maximum.
-62 to +260°C
C4 Silicone over steel monocoil. moderate crush resistance. -62 to +260°C
C5 PTFE over SS Interlok. Provides vapor barrier protection, maximum
strength, wide temperature range. Has poor flexibility.
-270 to +260°C
C6 PVC low temperature shrinkwrap over Polyethylene Wrap.
Non-metallic with light crush resistance, good for long lengths.
+10 to +107°C
C7 PTFE. For high vacuum applications. Does not
outgas. Wide temperature range, poor flexibility
-270 to +260°C
C8 PVC Only. Good flexibility, no crush resistance. +10 to +107°C
C9 Annealed stainless steel tubing (semi-rigid), provides vapor
barrier protection, maximum strength, widest temperature range. Has
very poor flexibility.
-270 to +850°C
C10 Silicone over SS Interlok. Good strength sealed sheathing, wide temperature range, good flexibility.
-62 to +260°C

Polyolefin Shrink Tubing, moderate flexibility, poor crush resistance, good vapor barrier, radiation resistant. Good to 300°C for short periods of time

-55 to +135°C

Polyolefin over SS interlok, moderate flexibility, crushproof, good vapor barrier, radiation resistant. Good to 300°C for short periods of time.

-55 to +135°C

Furcation Tubing: PVC/Kevlar/PTFE. High tensile strength, light crush resistance. Good for small diameter fiber models such as D6, D12, D20, D21, RC19, RC20, RC22

+10 to +85°C

Braided SS over PTFE. Very poor flexibility, liquid tight, good for high pressure. Available with O.D. sizes 0.312" (with 2" minimum bend radius) and larger

-55 to +200°C

Quartz Fiber Optic Cables and Sensor Tips

Quartz fibers are required for use in applications where the temperatures exceed the limitations of glass fibers, and also in radiation environments. Probes made using quartz fibers and high temperture adhesives can operate up to 800°C. Quartz probes will cost much more than probes made using glass fibers. Please contact the factory for further information.


Analog Output Amplifiers - 0°C to 70°C
DMS Amplifiers with LCD - 0°C to 50°C
DMS Electronics without LCD - 0°C to 70°C