Calibration:
  • ANSI : American National Standards Institute
  • ANSI Type J, the positive wire is iron, the negative wire is Constantan (45% nickel, 55% copper). This type is capable of temperatures (when insulated with compacted 96% pure Magnesium Oxide, MgO and stainless steel sheath) from 32 to 1500 deg. F (0 to 815 deg.C). The lead wire inner insulation color code is white on the positive iron leg [magnetic], and red on the negative Constantan [non magnetic].
  • ANSI Type K, the positive wire is Chromel (90% nickel, 10% chromium), the negative wire is Alumel (95% nickel, 2% aluminum, 2% manganese, 1% silicon). This type is capable of temperatures (when insulated with compacted 96% pure Magnesium Oxide, MgO and an outer sheath) from -32 to 2300 deg. F (-35 to 1260 deg.C). If your average application temperature is between 600 to 1100 deg. F it is recommended to use Type J calibration due to short range ordering that can cause a drift of +2 to +4 deg. F in a short period of time, a few hours. The lead wire inner insulation color code is yellow on the positive Chromel leg [non magnetic], and red on the negative Alumel [magnetic].
  • ANSI Type T, the positive wire is pure Copper, the negative wire is Constantan (45% nickel, 55% copper). This type is capable of temperatures (when insulated with compacted 96% pure Magnesium Oxide, MgO and stainless steel sheath) from 32 to 660 deg. F (0 to 350 deg.C). The lead wire inner insulation color code is blue on the positive iron leg, and red on the negative Constantan. When no lead wire is apparent the polarity is determined visually, the copper “colored” wire is the positive and the “white metal” appearing wire is the negative.
  • ANSI Type E, the positive wire is Chromel (90% nickel, 10% chromium), the negative wire is Constantan (45% nickel, 55% copper). This type is capable of temperatures (when insulated with compacted 96% pure Magnesium Oxide, MgO and an outer sheath) from 32 to 1650 deg. F (0 to 900 deg.C). If your average application temperature is between 600 to 1100 deg. F it is recommended to use Type J calibration due to short range ordering that can cause a drift of +1 to +3 deg. F in a short period of time, a few hours. The lead wire inner insulation color code is purple on the positive Chromel leg [non magnetic], and red on the negative Constantan [non magnetic]. When no lead wire is apparent, the polarity can only be determined by performing a thermocouple function check.
  • Other calibrations or thermocouple types such as N, R, S, and others not listed, are available, please consult the factory for your special request.
ISA CONDUCTOR & CHARACTERISTICS TEMPERATURE LIMITS OF ERROR  
TYPE positive negative RANGE standard special APPLICATION NOTES
J Iron
(magnetic)
Constantan
(non-magnetic)
0 to 530 F
530 to 1400 F
+/- 4F
+/- 3/4%
+/- 2F
+/- 3/8%
Reducing atmosphere recommended. Iron oxides rapidly at elevated temperatures.
T Copper
(non-magnetic)
Constantan
(non-magnetic)
-75 to 200 F
200 to 700 F
+/- 1-1/2F
+/- 3/4%
+/- 3/4F
+/- 3/8%
Can be used in oxidizing or reducing atmospheres rust and corrosion resistant. Fine for low temperatures & Cryogenic.
K Chromel
(non-magnetic)
Alumel
(magnetic)
0 to 530 F
530 to 2300 F
+/- 4F
+/- 3/4%
+/- 2F
+/- 3/8%
Oxidizing atmosphere recommended. Vented protection tube suggested in reducing atmosphere.
E Chromel
(non-magnetic)
Constantan
(non-magnetic)
0 to 600 F
600 to 1600 F
+/- 3F
+/- 1/2%
+/- 3/8%
Oxidizing atmosphere recommended. Highest EMF output of thermocouples commonly used.
S Platinum
10% Rhodium
(non-magnetic)
Platinum
(non-magnetic)
0 to 1200 F
1200 to 2700 F
+/- 5F
+/- 1/2%
+/- 2-1/2F
+/- 1/4%
Oxidizing atmosphere recommended. Easily contaminated. The accepted laboratory standard in premium grade due to its reproducibility.
R Platinum
13% Rhodium
(non-magnetic)
Platinum
(non-magnetic)
0 to 1200 F
1200 to 2700 F
+/- 3F
+/- 1/4%
+/- 1F
+/- 1/10%
Same conditions as 10% above but has 13% Rhodium slightly higher emf. Mostly used in industrial applications.
N Nicrosil
(non-magnetic)
Nisil
(non-magnetic)
0 to 530 F
530 to 2300 F
+/- 4F
+/- 3/4%
+/- 2F
+/- 3/8%
Better Resistance to Oxidation and longer life at high temperatures than Type K.
B Platinum
13% Rhodium
Platinum 1000 to 3200 F +/- 1/2% +/- 1/2%
Can be used in a vacuum with limited life.