AM1968 Capsule SPRT


Product Description

AM1968 Capsule SPRT

  • Rtpw Drift: < 1 mK after thermal cycle
  • Temperature range: -260 °C (13K) to 100 °C (373K)
  • Short term stability: <0.001 °C at 0.01 °C
  • Nominal Rtpw: 25 ohm at 0 °C
AM1968 Platinum Capsule SPRT covers temperatures from -260°C to 100 °C. The capsule construction makes this SPRT a preferred primary standard for cryogenic applications and other applications where space is limited or stem conduction is a concern for a long stem SPRT.
The sensing element is made of pure platinum wires with a temperature coefficient of 0.003925 Ω/Ω/°C. The coiled platinum wires are mounted in a way that is strain free and enclosed in a platinum capsule, which is sealed by glass. The special sealing glass has a thermal expansion coefficient that matches with that of the platinum wire to ensure the capsule SPRT is sealed permanently in the entire temperature range. A uniquely designed support structure provides excellent performances of stability, mechanical shock, and thermal cycle performance. The SPRT achieves a high level of stability and repeatability in performance and fully meets ITS-90 criteria for reference thermometers.


  • Temperature range: -260 °C to 100 °C
  • Long term drift: <0.003 °C at TPW after 1 year, <0.001 °C typical
  • Short term stability: 0.001 °C at 0.01 °C
  • Temperature Coefficient: 0.003925 Ω/Ω/°C
  • W(Ga) >= 1.11807
  • W(Hg) <= 0.844235
  • Platinum sheath


Temperature Range
-260 °C to 100 °C
Resistance at 0.01 °C
Nominal 25 Ω
Temperature Coefficient
0.003925 Ω/ Ω/°C
Drift at 0.01 °C*
< 0.003 °C after 1 year, < 0.001 °C typical
Short Term Stability
±0.001 °C
Thermal Shock
±0.001 °C after thermal cycles from minimum to maximum temperatures
0.0015 °C at 1 mA current
Resistance Ratios
W(Ga)>=1.11807, W(Hg)<=0.844235
Measurement Current
1 mA
Sensor Length
42 mm
Filling Gas
Sheath Material
Sheath diameter 5mm, glass head diameter 7.5mm, length 60mm
External Leads
4 platinum wires, 30mm
  *Long-term drift rate is for reference only. It could be affected by such facts as handling, application, and maintenance, etc.

Optional Accessories

Carrying Case included

    About us

    บริษัท เมสเชอร์เมนท์เอเชีย จำกัด
    Measurementasia Co.,Ltd.

    99 Moo. 3, Khlong 5, Khlong Luang,
    Pathumthani 12120



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