Location -> Products -> Temperature -> Thermocouple and Thermal Resistance -> Explosion-proof Thermocouple
Type：Explosion-proof Thermocouple
Illustrate：It is usually connected with display meter, recording meter and computer, etc. to directly measure temperature of liquid, vapor, gas and solid surface ranging from 0℃ to 1300℃ with explosives such as hydrocarbon on production spot.
Explosion-proof Thermocouple
Application
It is usually connected with display meter, recording meter and computer, etc. to directly measure temperature of liquid, vapor, gas and solid surface ranging from 0℃ to 1300℃ with explosives such as hydrocarbon on production spot.
Features
Various explosion-proof types, good explosion-proof performance
Spring thermal element with good shock-proof performance
Wide measuring range
High mechanical strength, good pressure-resistant performance
Operation Theory
Explosion-proof thermocouple has a junction box of enough strength with gaps inside it. All spare parts which might produce spark, electric arc, and dangerous high temperature are sealed in the junction box. When explosion within the box happens, fire and high temperature caused by explosion could be extincted and cooled with the gap. Thus, explosion separation could be realized.
Main Technical Parameters
Executive Standard
IEC584
GB/T16839-1997
JB/T5518-1991
GB3836
Insulation Resistance at Normal Temperature
The insulation resistance between electrode and protection tube of the thermocouple shall be no less than 1000MΩ m under condition that environment temperature is 20±15℃，relative humidity is more than 80%, and testing voltage is D.C.500V ±50V.
Certificates List
| Explosion-proof Class | Certificate No. | Certifying institution |
| d ⅡBT4 | GTB96450 | NEPSI |
| d ⅡBT4 | GTB96453 | NEPSI |
| d ⅡCT5 | GTB98339 | NEPSI |
| d ⅡCT5 | GTB97197 | NEPSI |
| iaⅡCT6 | GTB99412 | NEPSI |
Remarks: NEPSI National Explosion-Proof Security Inspection
Measuring Range & Tolerance
| Type | Graduation | Tolerance Class | |||
| I | II | ||||
| Tolerance Value | Measuring Range °C | Tolerance Value | Measuring Range °C | ||
| WRN | K | ±1.5°C | -40～+375 | ±2.5 °C | -40～+333 |
| ±0.004ltl | 375～1000 | ±0.0075 ltl | 333~1200 | ||
| WRM | N | ±1.5°C | -40～+375 | ±2.5°C | -40～+333 |
| ±0.004 ltl | 375～1000 | ±0.0075 ltl | 333～1200 | ||
| WRE | E | ±1.5°C | -40～+375 | ±1.5°C | -40～+333 |
| ±0.004 ltl | 375～800 | ±0.004 ltl | 333～900 | ||
| WRF | J | ±1.5°C | -40～+375 | ±1.5°C | -40～+333 |
| ±0.004 ltl | 375～750 | ±0.004 ltl | 333～750 | ||
| WRC | T | ±1.5°C | -40～+125 | ±1°C | -40～+133 |
| ±0.004 ltl | 125～350 | ±0.0075 ltl | 133～350 | ||
Indication of Explosion-proof Function
| d Ⅱ □ T□ | |||||||
| Temperature Group: T1-T6 | |||||||
| Explosion-proof Class: A, B, C | |||||||
| Electric Equipment for plant | |||||||
| Explosion Separation Type | |||||||
| Intrinsic Safety Type | |||||||
Electric Equipment Category
I –Electric Equipment for Coal Mine Well
II –Electric Equipment for Plant
Explosion-proof Class
It is divided into Class A, B, and C according to maximum test safety gap in explosive gas compound.
| Category | Class | Max.Test Safety Gap |
| Ⅱ | A | 0.9≤MESG |
| B | 0.5＜MESG＜0.9 | |
| C | MESG≤0.5 |
Temperature Group
It includes T1-T6 according to maximum surface temperature allowed of open part.
| Temperature Group | Max. Surface Temperature Allowed |
| T1 | 450 |
| T2 | 300 |
| T3 | 200 |
| T4 | 135 |
| T5 | 100 |
| T6 | 85 |
Explosion-proof Class
EXd II □ T □
EXia II □T □
Protection Class
IP65
Junction Box
Terminal
Type Naming Method
| W | Temperature instrument | |||||||
| R | Thermocouple | |||||||
| Thermal Element Material | ||||||||
| M | NiCrSi-NiSi | |||||||
| N | NiCr-NiSi | |||||||
| E | NiCr-CuNi | |||||||
| F | Fe- CuNi | |||||||
| C | Cu- CuNi | |||||||
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Filament | |||||||
| blank Simplex | ||||||||
| 2 | 2 Duplex | |||||||
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Mounting &fixing | |||||||
| 1 Without fixing device | ||||||||
| 2 Threaded connector | ||||||||
| 4 Fixed flange | ||||||||
| 5 Elbow tube connector | ||||||||
| 7 Straight tube connector | ||||||||
| 8 Fixed threaded tube connector | ||||||||
| 9 Movable threaded tube connector | ||||||||
| Junction box | ||||||||
| 4 Explosion-proof Type | ||||||||
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Protection Tube Diameter | |||||||
| 0Φ16 | ||||||||
|
Measuring End G Variable cross section |
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| W | R | N | 2 | 2 | 4 | 0 | G | Model example |
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