When standard 1/8" or 1/4" probes are too large — for surface mapping, biological research, semiconductor wafer profiling, small components, or tight geometric constraints — Thermometrics manufactures miniature thermocouple and RTD sensors with ODs from 0.010" (0.25mm) using fine thermocouple wire and hypodermic-tube MIMS construction.
Bare thermocouple wire, 36–44 AWG, with twisted or welded junction. No sheath — the smallest possible thermal mass. Used for gas temperature measurement in small passages, biological tissue (animal studies), and point-contact surface measurement where sheath OD must be minimised to avoid disturbing the measured object.
MgO-insulated thermocouple in a hypodermic-gauge stainless steel sheath — 0.020" (0.5mm) to 0.062" (1.6mm) OD. Can be bent to complex curves without cracking the insulation. Used for injection mold hot runner mapping, circuit board temperature profiling, and tight-clearance engine component measurement.
Thin-film Pt100 element in a small-OD stainless probe, 3.2mm (1/8") diameter or less, for high-accuracy miniature temperature measurement. Used in laboratory instruments, medical device testing, clean room monitoring, and pharmaceutical stability chambers. IEC 60751 Class A, 4-wire.
| Parameter | TC-MINI-1 Fine Wire | TC-MINI-2 Hypodermic MIMS | RTD-MINI-1 Miniature Pt100 |
|---|---|---|---|
| OD / Size | Wire: 0.002" to 0.010" | 0.020" to 0.062" (0.5–1.6mm) | 3.2mm (1/8") std; 2.0mm custom |
| Type / Element | K, J, T, E — ASTM E230 | K, J, T — ASTM E230 | Pt100, IEC 60751 Class A |
| Insulation | PTFE, polyimide, or ceramic fiber | MgO — swaged | MgO — swaged |
| Sheath | None (bare wire) | 316SS hypodermic tube | 316SS drawn tube |
| Bend Radius | N/A — flexible wire | Min 5× OD before calibration | Not recommended to bend |
| Response Time | <10 ms (40 AWG, exposed) | 0.1 to 0.5 sec (sheath OD dep.) | 0.5 to 2 sec |
| Max Temp | Type K: 650°C (PTFE insulated) | Type K: 1100°C (ceramic MgO) | 300°C std; 600°C high-temp |
| Lead Length | 6" to 120" | 6" to 48" | 12" to 72" |
| Termination | Mini TC connector or bare leads | Mini TC connector or bare leads | Bare leads or M8 connector |
Talk directly to the engineering team that builds your assemblies. No bots, no call centers.