The high—temperature insulation resistance of insulated sheathed thermocouple shall comply with the stipulations stated below:
| Graduation Mark | Test temperature field(mm) | Test temperaturefC) | Insulation resistance(MO-m) |
| K,N,E,J | L=300 | 500±15 | >5 |
| T | 300±10 | >500 |
Test voltage of insulation resistance with different sheathed diameter shall comply with the stipulations shown in the table of normal temperature insulation resistance.
