NTC THERMISTORS:
TYPE BR32/42/55
GLASS ENCAPSULATED BEAD THERMISTOR
DESCRIPTION:
Large glass encapsulated bead thermistors on fine diameter
platinum alloy lead-wires.
FEATURES:
•
Suitable for most low cost temperature measurement,
•
•
•
•
•
•
control or compensation applications
Fast thermal response times
Rugged glass encapsulation provides hermetic seal and
better strain relief than large glass coated bead thermistors
Long term stability is better than large glass coated bead
thermistors
Suitable for self-heated applications such as liquid level
sensing or gas flow measurement
Recommended for all applications where the customer will
perform further assembly operations
Normal operating/storage temperatures range from
-80°C to:
105°C for Material system E0
200°C for Material system A1 through A4
300°C for Material systems A5 through D17
Unaffected by severe environmental exposures, including
nuclear radiation
Intermittent operation up to 600°C is permissible,
however, stability will be degraded.
DIMENSIONS:
•
•
OPTIONS:
•
Non-standard resistance tolerances
•
Non-standard resistance values
•
Reference temperature(s) other than 25°C - specify
•
Mounting in special housings or enclosures
•
Longer continuous leads
•
Welded or soldered extension leads - specify lead material, diameter, length and insulation, if any.
•
Solderable or weldable/solderable leads
•
Leads can be pre-tinned or treated for improved soldering
•
Calibration - specify temperature(s)
•
Interchangeable pairs or set, curve matching - specify temperature range(s) and tolerance(s)
•
Special aging and conditioning for high reliability applications
CODING:
The code number to be ordered may be specified as follows:
BR 55
K
A
752
N
Tolerance code letter (see NOTE 1 and TABLE B)
Zero-power resistance as 25°C (see NOTE 2)
Material System Code Letter (see TABLE A)
Lead configuration code letter.
“K” = adjacent leads with stub ends glass coated
“P” = opposite leads with stub ends glass coated
Nominal Bead Diameter in mils (specify 32, 42 or 55)
Style “BR” denotes RUGGEDIZED BEAD structure
NOTE 1:
Special tolerances are available on request. Consult factory for special resistance tolerances, non-standard
resistances and/or non-standard temperatures.
NOTE 2:
The zero-power resistance at 25°C, expressed in Ohms, is identified by a three digit code number. The first two digits
represent significant figures, and the last digit specifies the number of zeros to follow. Example: 7.5k Ohms= “752”.
The standard resistance values are from the 24-Value series decade as specified in Military Standard MS90178.
1.0 / 1.1 / 1.2 / 1.3 / 1.5 / 1.6 / 1.8 / 2.0 / 2.2 / 2.4 / 2.7 / 3.0
3.3 / 3.6 / 3.9 / 4.3 / 4.7 / 5.1 / 5.6 / 6.2 / 6.8 / 7.5 / 8.2 / 9.1
TABLE A: THERMAL AND ELECTRICAL PROPERTIES:
The following table lists the THERMAL and ELECTRICAL properties for all LARGE RUGGEDIZED THERMISTORS. All definitions and
test methods are per MIL-PRF-23648.
THERMISTOR SERIES:
BODY DIMENSIONS:
Nom. Diameter:
Max. Diameter:
Max. Length:
lead-wires:
Nom. Diameter:
Minimum Lead Length:
Lead Material:
Available Cuts:
BR32
BR42
BR55
.032"
.033"
.084"
(.81 mm)
(.84 mm)
(2.1 mm)
.042"
.046"
.095"
(1.1 mm)
(1.2 mm)
(2.4 mm)
.055"
.060"
.120"
(1.4 mm)
(1.5 mm)
(3.0 mm)
.003" (.08 mm)
.312" (7.9 mm)
Platinum Alloy
“K”
“P”
adjacent
opposite
.004" (.10 mm)
.312" (7.9 mm)
Platinum Alloy
“K”
“P”
adjacent
opposite
.004" (.10 mm)
.312" (7.9 mm)
Platinum Alloy
“K”
“P”
adjacent
opposite
MATERIAL SYSTEM:
CODE
R-vs-T
LETTER
CURVE
E
A
A
A
A
A
A
A
B
B
B
B
B
B
B
B
D
D
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
25/125
RATIO
5.0
11.8
12.5
14.0
16.9
19.8
22.1
22.7
29.4
30.8
32.3
35.7
38.1
45.0
48.1
56.5
75.6
81.0
Nominal
Resistance
Range @ 25°C
—
100
Ω
–
300
Ω
–
750
Ω
–
1.5 kΩ –
3.0 kΩ –
6.8 kΩ –
13 kΩ –
18 kΩ –
51 kΩ –
82 kΩ –
150 kΩ –
330 kΩ –
680 kΩ –
1.5 MΩ –
3.0 MΩ –
6.2 MΩ –
—
300
Ω
750
Ω
1.5 kΩ
3.0 kΩ
6.8 kΩ
13 kΩ
18 kΩ
51 kΩ
82 kΩ
150 kΩ
330 kΩ
680 kΩ
1.5 MΩ
3.0 MΩ
6.2 MΩ
10 MΩ
Nominal
Resistance
Range @ 25°C
30
Ω
51
Ω
150
Ω
360
Ω
750
Ω
1.5 kΩ
3.6 kΩ
6.2 kΩ
9.1 kΩ
27 kΩ
43 kΩ
75 kΩ
160 kΩ
360 kΩ
750 kΩ
1.5 MΩ
3.0 MΩ
8.2 MΩ
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
51
Ω
150
Ω
360
Ω
750
Ω
1.5 kΩ
3.6 kΩ
6.2 kΩ
9.1 kΩ
27 kΩ
43 kΩ
75 kΩ
160 kΩ
360 kΩ
750 kΩ
1.5 MΩ
3.0 MΩ
8.2 MΩ
20 MΩ
Nominal
Resistance
Range @ 25°C
30
Ω
51
Ω
150
Ω
360
Ω
750
Ω
1.5 kΩ
3.6 kΩ
6.2 kΩ
9.1 kΩ
27 kΩ
43 kΩ
75 kΩ
160 kΩ
360 kΩ
750 kΩ
1.5 MΩ
3.0 MΩ
8.2 MΩ
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
51
Ω
150
Ω
360
Ω
750
Ω
1.5 kΩ
3.6 kΩ
6.2 kΩ
9.1 kΩ
27 kΩ
43 kΩ
75 kΩ
160 kΩ
360 kΩ
750 kΩ
1.5 MΩ
3.0 MΩ
8.2 MΩ
20 MΩ
THERMAL TIME CONSTANT:
Still Air at 25°C:
Plunge into Water:
DISSIPATION CONSTANT:
Still Air at 25°C:
Still Water at 25°C:
POWER RATING: (in air)
Maximum Power Rating:
100% Max. Power to:
Derated to 0% at:
.035 Watts
150°C
300°C
.042 Watts
150°C
300°C
.050 Watts
150°C
300°C
.28 mW/°C
1.4 mW/°C
.33 mW/°C
1.65 mW/°C
.50 mW/°C
2.50 mW/°C
4.5 sec
90 msec
5 sec
140 msec
7 sec
200 msec
RESISTANCE -VS- TEMPERATURE CHARACTERISTICS: The nominal resistance range for the zero-power resistance at 25°C is shown
for each THERMISTOR Type and each available Material System. Each Material System is denoted by an ordering Code Letter,
a referenced Curve number and the nominal 25°C/125°C resistance ratio.
TABLE B: STANDARD TOLERANCES:
Tolerance Code Letter
± % Tolerance at 25°C
F
1
G
2
J
5
K
10
L
15
M
20
N
25
P
30
Q
40
R
50
S
Non-standard – consult factory
BOWTHORPE THERMOMETRICS
Crown Industrial Estate, Priorswood Road
Taunton, Somerset TA2 8QY UK
Tel +44 (0) 1823 335200
Fax +44 (0) 1823 332637
THERMOMETRICS, INC.
808 US Highway 1
Edison, New Jersey 08817-4695 USA
Tel +1 (732) 287 2870
Fax +1 (732) 287 8847
KEYSTONE THERMOMETRICS CORPORATION
967 Windfall Road
St. Marys, Pennsylvania 15857-3397 USA
Tel +1 (814) 834 9140
Fax +1 (814) 781 7969
