How to read a cable code: guides per coding system · Thermocouple cables (GB/T 4989, China) · China
Thermocouple cables (GB/T 4989, China): how to read the cable type names
Each name in Thermocouple cables (GB/T 4989, China) stands for a whole cable type: KX, for example, comes with its own construction, standard and rating. The decoder knows 10 types of this system. Below: how the names are built, every type with its rating, and the sources the table names.
How a name is built
The type table does not split these names into parts: each name stands for the whole cable type.
Every type in Thermocouple cables (GB/T 4989, China)
| Type | Description | Rating |
|---|---|---|
SC | SC (GB/T 4989): compensating cable for type S thermocouples, copper / copper-nickel 0.6 | Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±30 µV (2.5 °C), normal ±60 µV (5.0 °C) at 1000 °C, heat resistant normal only |
RC | RC (GB/T 4989): compensating cable for type R thermocouples, copper / copper-nickel 0.6 | Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±30 µV (2.5 °C), normal ±60 µV (5.0 °C) at 1000 °C, heat resistant normal only |
KCA | KCA (GB/T 4989): compensating cable for type K thermocouples, variant A, iron / copper-nickel 22 | Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C |
KCB | KCB (GB/T 4989): compensating cable for type K thermocouples, variant B, copper / copper-nickel 40 | Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C; no heat resistant KCB; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C |
KX | KX (GB/T 4989): extension cable for type K thermocouples, NiCr10 / NiSi3 | Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C |
NC | NC (GB/T 4989): compensating cable for type N thermocouples, iron / copper-nickel 18 | Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±43 µV (1.1 °C), normal ±86 µV (2.2 °C) at 900 °C |
NX | NX (GB/T 4989): extension cable for type N thermocouples, NiCr14Si / NiSi4Mg | Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±43 µV (1.1 °C), normal ±86 µV (2.2 °C) at 900 °C |
EX | EX (GB/T 4989): extension cable for type E thermocouples, NiCr10 / CuNi45 | Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±81 µV (1.0 °C), normal ±138 µV (1.7 °C) at 500 °C |
JX | JX (GB/T 4989): extension cable for type J thermocouples, iron / CuNi45 | Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±62 µV (1.1 °C), normal ±123 µV (2.2 °C) at 500 °C |
TX | TX (GB/T 4989): extension cable for type T thermocouples, copper / CuNi45 | Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±30 µV (0.5 °C), normal ±60 µV (1.0 °C) at 300 °C |
Marks written next to the name
Words and marks the decoder reads next to a type name of this system: each adds a property to whatever type it is written with.
| Mark | Meaning | Written as |
|---|---|---|
| -G | G: general use, normal tolerance class (GB/T 4989-2013 cl. 3.2; the normal class is not marked) | -G |
| -H | H: heat resistant, up to 200 °C, normal tolerance class (GB/T 4989-2013 cl. 3.2, Table 3; the normal class is not marked) | -H |
| -GS | GS: general use, precision tolerance class S (GB/T 4989-2013 cl. 3.2, Table 4) | -GS |
| -HS | HS: heat resistant, up to 200 °C, precision tolerance class S (GB/T 4989-2013 cl. 3.2, Tables 3 and 4) | -HS |
| GB/T 4989 | Standard named in the marking: GB/T 4989-2013, extension and compensating cables for thermocouples (cl. 4.5) | GB/T 4989 |
| V70V70 | V70V70: insulation V70 and sheath V70, PVC rated 70 C; solid conductors (not marked); unscreened (not marked); general use grade G, 0 or -20 to +70 C (GB/T 4989-2013 cl. 4.5, Table 3) | V70V70 |
| V70V70P | V70V70P: insulation V70 and sheath V70, PVC rated 70 C; solid conductors (not marked); P screened; general use grade G, 0 or -20 to +70 C (GB/T 4989-2013 cl. 4.5, Table 3) | V70V70P |
| V70V70R | V70V70R: insulation V70 and sheath V70, PVC rated 70 C; R stranded (flexible) conductors; unscreened (not marked); general use grade G, 0 or -20 to +70 C (GB/T 4989-2013 cl. 4.5, Table 3) | V70V70R |
| V70V70RP | V70V70RP: insulation V70 and sheath V70, PVC rated 70 C; R stranded (flexible) conductors; P screened; general use grade G, 0 or -20 to +70 C (GB/T 4989-2013 cl. 4.5, Table 3) | V70V70RP |
| V100V100 | V100V100: insulation V100 and sheath V100, PVC rated 100 C; solid conductors (not marked); unscreened (not marked); general use grade G, 0 or -20 to +100 C (GB/T 4989-2013 cl. 4.5, Table 3) | V100V100 |
| V100V100P | V100V100P: insulation V100 and sheath V100, PVC rated 100 C; solid conductors (not marked); P screened; general use grade G, 0 or -20 to +100 C (GB/T 4989-2013 cl. 4.5, Table 3) | V100V100P |
| V100V100R | V100V100R: insulation V100 and sheath V100, PVC rated 100 C; R stranded (flexible) conductors; unscreened (not marked); general use grade G, 0 or -20 to +100 C (GB/T 4989-2013 cl. 4.5, Table 3) | V100V100R |
| V100V100RP | V100V100RP: insulation V100 and sheath V100, PVC rated 100 C; R stranded (flexible) conductors; P screened; general use grade G, 0 or -20 to +100 C (GB/T 4989-2013 cl. 4.5, Table 3) | V100V100RP |
| FB | FB: insulation F (PTFE), sheath B (alkali-free glass fibre yarn); solid conductors (not marked); unscreened (not marked); heat-resistant grade H, up to 200 C (GB/T 4989-2013 cl. 4.5, Table 3) | FB |
| FBP | FBP: insulation F (PTFE), sheath B (alkali-free glass fibre yarn); solid conductors (not marked); P screened; heat-resistant grade H, up to 200 C (GB/T 4989-2013 cl. 4.5, Table 3) | FBP |
| FBR | FBR: insulation F (PTFE), sheath B (alkali-free glass fibre yarn); R stranded (flexible) conductors; unscreened (not marked); heat-resistant grade H, up to 200 C (GB/T 4989-2013 cl. 4.5, Table 3) | FBR |
| FBRP | FBRP: insulation F (PTFE), sheath B (alkali-free glass fibre yarn); R stranded (flexible) conductors; P screened; heat-resistant grade H, up to 200 C (GB/T 4989-2013 cl. 4.5, Table 3) | FBRP |
Common questions
What is KX cable?
KX: KX (GB/T 4989): extension cable for type K thermocouples, NiCr10 / NiSi3. Rating: Use temperature (Table 3, pp. 4, 5): general use G -20 to 70 or -20 to 100 °C, heat resistant H -25 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C. Standard: GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard); tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D).
What is SC cable?
SC: SC (GB/T 4989): compensating cable for type S thermocouples, copper / copper-nickel 0.6. Rating: Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±30 µV (2.5 °C), normal ±60 µV (5.0 °C) at 1000 °C, heat resistant normal only. Standard: GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard); tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D).
Thermocouple cables (GB/T 4989, China): what does -G mean next to a cable name?
-G: G: general use, normal tolerance class (GB/T 4989-2013 cl. 3.2; the normal class is not marked). Written as -G.
What is RC cable?
RC: RC (GB/T 4989): compensating cable for type R thermocouples, copper / copper-nickel 0.6. Rating: Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±30 µV (2.5 °C), normal ±60 µV (5.0 °C) at 1000 °C, heat resistant normal only. Standard: GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard); tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D).
What is KCA cable?
KCA: KCA (GB/T 4989): compensating cable for type K thermocouples, variant A, iron / copper-nickel 22. Rating: Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C, heat resistant H 0 to 200 °C; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C. Standard: GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard); tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D).
What is KCB cable?
KCB: KCB (GB/T 4989): compensating cable for type K thermocouples, variant B, copper / copper-nickel 40. Rating: Use temperature (Table 3, pp. 4, 5): general use G 0 to 70 or 0 to 100 °C; no heat resistant KCB; tolerance at the hot end (Table 4, p. 6): precision S ±44 µV (1.1 °C), normal ±88 µV (2.2 °C) at 900 °C. Standard: GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard); tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D).
Sources the type table names
Standards named in the table
- GB/T 4989-2013 Table 1, p. 2 (from the SAMR portal, read 2026-10-29, seen: standard)
- tolerances after ASTM E230-2003, the IEC 60584-3:2007 colours as an option (Annex D)
Documents and pages the readings were taken from
- openstd.samr.gov.cn
- GB/T 4989-2013 cl. 3.2 (p. 2), Table 3 (pp. 4 to 5) and cl. 4.5 with its note (p. 5), from the SAMR portal https://openstd.samr.gov.cn/ (read 2026-11-01 on the page image, seen: standard)
Taken from the type table of this site, with the sources named above. Check the manufacturer's datasheet before you specify a cable.
Every type in Thermocouple cables (GB/T 4989, China) · Decode your own designation