Product Overview
The Raytek Mi3 is a two-piece modular IR sensor: a miniature single-color sensing head on a 1 m cable plugs into a separate communication box that the head is auto-detected by (plug & play), and one 4-channel box networks up to eight heads. The same head model spans several spectral ranges — LT (8–14 µm), G5 (5 µm glass), and the 2M / 1M short-wave metals heads — so a single platform covers organics, glass, and high-temperature metal by head choice. Heads are tiny (down to a 0.5 mm spot with the Close Focus Lens) and tolerate up to 180°C uncooled, which is what makes the Mi3 the OEM and multi-point embedding sensor in the compact line. It is sold through authorized distribution — nationwide, with unit pricing on our webstore and select SKUs stocked at Brooklyn.
Other FPI / Raytek / Ircon series
CM / CI OEM Sensors — one-piece embedded OEM sensor — no separate box
Raynger 3i Plus — portable handheld spot-check tool for the hot end
Thermalert 4.0 — fixed single-color spot sensors for a permanent control point
Endurance — integrated single-color and 2-color ratio pyrometers, 50–3200°C
Key Features & Benefits
- Separate the head from the electronics — the small sensing head goes where the heat and the tight space are, on a rugged cable, while the comm box with the display and outputs mounts somewhere cooler and accessible. The form factor for embedding a sensor in a machine or a hot, cramped spot.
- One box, up to eight heads, plug & play — a 4-channel modular box auto-detects each head and supports up to eight on one networked enclosure, so a multi-zone or multi-point install wires back to a single box instead of one transmitter per point. Cuts the panel count on a multi-point measurement.
- One head model, many wavelengths — the same Mi3 platform is offered in 8–14 µm, 5 µm glass, and 1.6 / 1 µm metals heads, so you standardize on one sensor family across very different targets. Match the head to the material without changing platforms.
- Runs hot without cooling — the high-ambient LTH head holds up to 180°C uncooled, and air or water cooling extends the envelope further — so the sensor survives near the process before you reach for a cooling jacket. Fewer accessories to keep a small sensor alive on a hot line.
- Pick the box to fit the network — the comm box carries the analog, thermocouple, relay, and fieldbus outputs, so USB, RS485/Modbus/Profibus, or Profinet/Ethernet is a box choice rather than a sensor change. The interface is configured at the box, not baked into the head.
Specifications
- Form factor
- Two-piece modular sensor — a miniature infrared sensing head on a 1 m (3.3 ft) cable plus a separate communication box; the two are ordered as separate items. The box detects the head automatically (plug & play), and a 4-channel modular box supports up to 8 sensing heads on one box, so a multi-point install runs from a single networked enclosure.
- Measurement principle
- Single-color (1-color) non-contact infrared pyrometer. The same head model covers multiple spectral ranges, so one platform serves low-temperature organics, glass, and high-temperature metals by head selection.
- Models / spectral variants
- LT (8–14 µm general purpose, in LTS standard, LTF fast, and LTH high-ambient heads), G5 (5 µm, dedicated glass), 2M (1.6 µm, metals), and 1M (1 µm, high-temperature metals). The LT head reaches 1000°C in the LTS20 (22:1), LTF, and LTH20 variants.
- Temperature range
- LTS02 / LTS10 / LTH10: −40 to 600°C (−40 to 1112°F)
LTS20 / LTF / LTH20: 0 to 1000°C (32 to 1832°F)
G5: 250 to 1650°C (482 to 3002°F)
2M: 250 to 1400°C (482 to 2552°F)
1M: 500 to 1800°C (932 to 3272°F) - Spectral response (wavelength)
- LT 8–14 µm · G5 5 µm · 2M 1.6 µm · 1M 1 µm — match the head wavelength to the target material.
- Optical resolution (D:S)
- At 90% energy: LTS 2:1, 10:1, or 22:1 typ. (21:1 guaranteed) · LTH 10:1, 22:1 typ. · LTF 10:1 · G5 10:1 · 1M / 2M 100:1. A Close Focus Lens (LT, G5) reads spots down to 0.5 mm (0.02 in).
- Accuracy
- LT, G5: ±(1% of reading or 1°C), whichever is greater (±2°C below 20°C target)
1M, 2M: ±(0.5% of reading + 2°C). At 23°C ±5°C ambient, ε = 1.0, and calibration geometry. - Repeatability
- LT, G5: ±0.5% of reading or ±0.5°C
1M, 2M: ±(0.25% of reading + 1°C). - Response time
- LTS (standard), LTH, G5: 130 ms (90% value)
LTF (fast): 20 ms
1M, 2M: 10 ms. - Emissivity / transmissivity
- Emissivity ε adjustable 0.100 to 1.100; transmission 0.100 to 1.000. Set per material (or use the published emissivity table).
- Signal processing
- Peak hold, valley hold (adjustable up to 998 s), and a variable averaging (flicker) filter on the box; user-configurable inputs allow remote emissivity, background-radiation compensation, and trigger/hold or laser switching.
- Outputs
- Box-dependent: 4–20 mA, 0–20 mA, 0–5 V, or 0–10 V analog; J / K / R / S thermocouple emulation; a 0–5 V head-ambient signal; and an isolated solid-state alarm relay (48 V / 300 mA). The DIN-6TE analog box provides 4 galvanically isolated analog channels.
- Communications
- USB 2.0 standard on every box; optional RS485 (ASCII), Profibus DP-V0, Modbus RTU, Profinet IO, and Ethernet TCP/IP (with HTTP server and a 64 MB data logger), depending on box model.
- Display & user interface
- Metal box (MI3COMM) and the user-interface DIN-rail boxes carry a high-resolution LCD display and button interface; a no-interface DIN box (MI3MCOMMN) is available for purely remote installs.
- Sighting / aiming
- Laser sighting on the 1M and 2M heads (automatic switch-off at 65°C ambient).
- Ambient temperature / cooling
- Head ambient (uncooled): LT / G5 −10 to 120°C, LTH to 180°C, 1M / 2M 0 to 120°C. An air-cooling jacket (LT, G5) extends the head to 200°C (392°F); a water-cooled housing is available for the 1M / 2M heads. The communication box is rated −10 to 65°C.
- Environmental & IP rating
- Head and metal box IP65 (NEMA-4); EMC per EN 61326-1. Rugged PUR head cable, silicone- and halogen-free, resistant to oil, bases, and acids.
- Housing & mounting
- Threaded miniature head with mounting nut; adjustable / fixed brackets, air-purge collar, and protective window are stock accessories. The box is a die-cast-zinc metal enclosure (MI3COMM) or a DIN-rail mountable plastic box (3TE / 4TE / 6TE widths).
- Power
- Communication box: 8 to 32 VDC, 5 W.
- Software
- DataTemp Multidrop PC software for remote monitoring, configuration, and data logging across a network of boxes.
- Hazardous-area option
- Intrinsically safe sensing heads (MI3…IS) rated II 2G Ex ib IIC T4 Gb (gas) / II 2D Ex ib IIIC T135°C Db (dust), with a dedicated Ex power supply (MI3ACIS). Specify the area classification with the order.
- Ordering & stock
- Authorized Raytek distribution — sold nationwide with unit pricing published on our webstore and shipped from the Brooklyn warehouse; select Mi3 SKUs are stocked for same / next-day shipment while others are special order. The head and the comm box are ordered separately; longer head cables (3, 8, 15, 30 m) are specified at order.
Common Applications
- Embedding a non-contact sensor inside OEM machinery where space and heat rule out a transmitter
- Multi-point or multi-zone monitoring run back to one 8-head networked box
- Glass surface temperature with the dedicated 5 µm G5 head
- Induction-heated and high-temperature metal targets with the 1M / 2M short-wave heads
- Small-target measurement (down to 0.5 mm) with the Close Focus Lens
- Hazardous-area points using the intrinsically safe MI3…IS heads
The Mi3 is the modular, embeddable single-color sensor of the compact line — small head, remote box, up to eight points per box. For a self-contained embedded probe with no separate box, the CM / CI OEM sensors fit; for a handheld spot-check tool, the Raynger 3i Plus is the answer. Use the input form to send the target material, temperature range, working distance, and output, and the head and box follow.
Design & Selection Considerations
- Order the head and the box as two line items — an Mi3 system is one sensing head plus one communication box, ordered separately — the head sets the wavelength, temperature range, and optics; the box sets the outputs and fieldbus. Decide both before you order. A head with no box (or the wrong box) does not measure.
- Choose the spectral head by the target, not by habit — an 8–14 µm LT head reads organics and painted surfaces; glass wants the 5 µm G5; hot metal wants the 1M / 2M short-wave head. The wrong wavelength reads the wrong layer no matter how you set emissivity. Wavelength is the first decision, before optics or output.
- Size the optics so the spot fits the target — a single-color sensor averages in whatever surrounds an underfilled spot, so the measured spot at the working distance must sit fully within the target — the Close Focus Lens reaches 0.5 mm for small targets, and the 1M / 2M heads run 100:1 for long standoffs. Confirm the spot size at your actual mounting distance.
- Keep the head in its ambient band, then cool — a head past its rated ambient drifts and ages; use the high-ambient LTH head, an air-cooling jacket (to 200°C on LT / G5), or a water-cooled housing on the 1M / 2M before the install sees more heat than the head is rated for. Cooling is cheaper than a cooked sensor.
- Match the comm box to the control system up front — analog 4–20 mA, thermocouple emulation, Modbus, Profibus, Profinet, or Ethernet are box options — pick the box that speaks to your PLC or DCS, and the DIN-6TE analog box if you need four isolated analog channels. The box, not the head, decides how the data leaves the sensor.
To spec the right Raytek Mi3 sensor:
To spec the right sensor, have ready: the target material and its emissivity (or whether it is a bare / oxidized metal), the process temperature range, the wavelength / spectral fit for that material, the working distance and target size (which set the optics / D:S and the spot size at distance), whether a fixed or handheld instrument suits, the mounting and ambient conditions (and any cooling or air-purge need), and the required output and communications. The more complete the application data, the faster and tighter the configuration.
IR Pyrometer Application Sheet ›Talk to an engineer directly — Scott Prater, Principal · 917-580-0878 · scott@pratertechnical.com
Specifications compiled by Prater Technical Partners from Fluke Process Instruments product datasheets.