Specifications

18
temperature measurement products
0.25
APPROX
2.00
APPROX
18.0”72.0”
1.50
REF
STRAIN RELIEF
0.50±0.01
0.250 ±0.005
0.25
APPROX
2.00
APPROX
12.0”72.0”
1.50
REF
STRAIN RELIEF
0.50±0.01
0.250 ±0.005
0.25
APPROX
2.00
APPROX
15.0”72.0”
1.50
REF
STRAIN RELIEF
0.50±0.01
0.250 ±0.005
RTD Probes
The Techne Model WSP425 and SSP670 PRT’s are an excellent choice for use as a reference sen-
sor in all types of systems including dry block calibrators, liquid calibration baths, ovens, reactors
and other applications where temperature needs to be accurately measured.
Our PRT’s offer proven and reliable performance for critical temperature measurements. They
can be used with our Tecal Accu-Temp indicator or any comparable unit. Both models include a
carrying case and ITS-90 calibration (NIST traceable) certificate with coefficients and resistance vs.
temperature table. The SSP670 has excellent performance, specifications and wide temperature
range at an affordable price, while the WSP425 is designed for measurements within a narrower
temperature range.
The model WSP425 has a NIST calibrated operating range of -50 to +350ºC with an accuracy of
±0.07ºC, while the model SSP660 has a NIST calibrated operating range of -200 to +660ºC with
an accuracy of ±0.05 up to 420ºC
660ºC Secondary Standard PRT
Model SSP670 PRTs are assembled using our special wire wound RTD elements and assembled
into inconel sheaths. The SSP670 PRT has similar accuracy and long-term stability specifications
you would find in much higher priced secondary standard PRTs.
The SSP670 PRT can be used as a working standard in calibration baths, furnaces, fluidized baths,
dry block calibrators and other any other temperature calibration work requiring a high level of
accuracy and repeatability.
Technical Specification
Resistance at 0° C: 100 ohms
Temperature range: -200 to 660°C
Calibrated temperature range: -196 to 660°C
Temperature coefficient: 0.003925 Ω /Ω /° C minimum
Stability: R0 typical drift < 0.03°C after 500 hours at 660° C
Thermal shock: R0 typical drift < 0.010° C after 100 times
from 25 to 660°C
Dimensions: 0.25” dia. x 18” L inconel sheath as standard,
custom sizes available
Tolerance at 0° C: ± 0.06%, IEC DIN class A
Lead wires: 4 wire PTFE insulated, stranded 22 AGW copper x 6” long
Calibration
Each WSP670 includes an ITS-90 NIST traceable calibration with a+, b+, c+, a- and b- coefficients
and R vs T table. A padded soft carrying case is also included.
Calibrated uncertainty (K=2) FWSP660M 660ºC Secondary Std 6mm PRT
FWSP660I 660ºC Secondary Std ¼” PRT
-196°C ±0.050°C
-38°C ±0.035°C
0°C ±0.020°C
232°C ±0.030°C
420°C ±0.045°C
660°C ±0.055°C
Accessories
FWSP660M 660ºC Secondary Std 6mm PRT
FWSP660I 660ºC Secondary Std ¼” PRT