glass beads

Download PDF:

Glass Bead Thermistors Glass Bead Thermistors (334 KB)

Small Bead Thermistors

Sensor Scientific small bead thermistors, sometimes referred to as glass beads, offer the advantages of small size and mass, very fast thermal response time, extreme sensitivity to current and voltage changes, and high stability. Typical applications include thermodilution cardiac catheters and other biomedical assemblies, fluid flow and fluid level measurement, thermal conductivity measurement, gas analysis, and small surface area temperature measurement.

Features:

  • Superior Stability
  • Very Fast Response Time
  • Low Thermal Mass

Options:

  • Custom Lead Lengths
  • Non-Standard Resistance Tolerances
  • Precision Calibration At Multiple Temperatures
  • Custom Value-Added Assembly Options

Specifications:

  • Operating Temperature Range: -40°C to 300°C.
  • Standard Resistance Tolerance: ±25%
  • Time Constant: 1 Sec. Typ. In Still Air
  • Dissipation Constant: 0.1Mw/°C In Still Air

SMALL BEAD THERMISTORS MECHANICAL AND THERMAL PROPERTIES

BODY DIMENSIONS
Diameter, nominal inches 0.014
  mm 0.36
 
Length, nominal inches 0.02
  mm 0.5
LEAD WIRES
Material: Platinum Alloy
Diameter, nominal inches 0.0011
  mm 0.28
 
Length, minimum inches 0.375
  mm 9.5
THERMAL PROPERTIES
Time constant, still air sec. 1
Dissipation constant, still air mW/°C 0.1

PART NUMBER SPECIFICATION:

To specify a part number, the following sequence should be used:

S14A10325 specifies a small bead thermistor with adjacent leads, 10000 ohms at 25 Deg. C., with a resistance tolerance of ±25%.

S14A10325 indicates small bead thermistor, .014" (0.36mm) nominal diameter

S14A10325 indicates lead configuration A: Adjacent leads B: Opposite leads

S14A10325 indicates zero power resistance at 25°C. The first two digits indicate significant figures, and the last digit indicates the number of zeros following the significant figures. In this example, "103" represents 10000 ohms.

S14A10325 indicates the resistance tolerance at 25°C, expressed in ±%. In this example, "25" indicates the standard tolerance of ±25%. Other typical tolerances include ±10%, 15%, 20%, and 30%. Non-standard tolerances available upon request.

Resistance Ratio Table

Resistance at 25 Deg. C.1 Beta25-125 R25/R125 a at 25 Deg. C.2 Part Number3
ohms Deg. Kelvin Ratio %/°C Adjacent Leads Opposite Leads
1000 3000 12.5 -3.33% S14A10225 S14B10225
2500 3090 13.5 -3.48% S14A25225 S14B25225
5000 3385 17.3 -3.71% S14A50225 S14B50225
10000 3550 19.8 -3.88% S14A10325 S14B10325
25000 3550 19.8 -3.88% S14A25325 S14B25325
50000 3690 22.4 -4.04% S14A50325 S14B50325
100000 4015 29.4 -4.40% S14A10425 S14B10425

"The information contained herein is believed to be accurate. The user, however, should verify the suitability of a particular product for a specific application. Sensor Scientific, Inc. does not warrant the accuracy of this information, and disclaims any liability with respect to its use"

 

Related Reading

Thermistors