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Platinum Temperature Sensors
UST temperature sensors are produced on a ceramic base chip with a thin film laser structured platinum layer.
This type of construction ensures the highest possible stability, combined with smallest dimensions. For operating temperatures up to 400° C connecting wires from silver-palladium are used, whilst on higher temperatures the wires are platinum wires.
Platinum temperature sensors are available in various shapes and dimensions. The resistance values can be produced to standards or customer specific requirements; all conform to the requirements of DIN EN 60751.
Depending on applications the sensors can be protected with glass or ceramic cases against environmental influences.
 Basic values from -200°C to +600°C (Acc. to EN 60751):
- Mean temperature coefficient between 0°C and +100°C: 3,85 x 10-3 K-1
The basic values for Pt temperature sensors can be calculated using the following formulae:
- For range -200°C to 0°C use:
Rt = R0 (1 + At +Bt² + C (t - 100°C) t³)
- For range 0°C to +850°C use:
Rt = R0 (1 + At +Bt²)
- whereby:
| Rt resistance in Ohm at temperature t |
A = 3,9083 x 10-3°C-1 |
| R0 nominal resistance at 0°C |
B = -5,775 x 10-7°C-2 |
| t temperature in °C |
C = -4,183 x 10-12°C-4 |
- All Pt temperature sensors referred to will be supplied to class B tolerances as standard:
?t in °C = ± (0,3 + 0,005[t])
- For applications with requirements for exceptionally close tolerances, temperature sensor elements to class A or better can be offered and supplied against extra costs.
?t in °C = ± (0,15 + 0,002[t])
In many applications the following tighter tolerances have proved to be especially suitable. They can be supplied at extra cost and against special order:
± 0,15°C at 0°C and ± 0,1°C at 0°C
Upon request and as special option we can also supply sensor elements where the constant of A and B would be measured at three points.
For measuring requirements with lesser accuracy we can supply sensor elements with wider tolerances at very attractive prices:
± 0,45°C at 0°C and ± 1,5°C at 0°C
Tolerance in °C are applicable for all nominal resistance values, whilst those in Ohm are only applicable for Pt 100. For other resistance values the tolerances in Ohm have to be multiplied with a factor Ro/100.
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