The Optris CTi P3 is a miniaturized two-piece infrared thermometer for non-contact temperature measurement of thin-film plastic materials from 95 °F to 1,112 °F (35 °C to 600 °C). Its 3.43 µm spectral range is chosen for precise measurement of thin-film plastics such as PE, PP, and PS. Polyolefin films absorb strongly at that wavelength, so even a thin film reads as an opaque surface rather than letting the sensor see through to whatever sits behind it. The sensing head sits in a massive housing and connects by cable to an electronics box with programming keys, a backlit LCD display, and a built-in USB interface. Response time is 15 ms.
Temperature range: 95 °F to 1,112 °F (35 °C to 600 °C)
Spectral range: 3.43 µm
Optical resolution: 15:1
Measurement uncertainty: ± 4.5 °F (± 2.5 °C) or ± 1%, whichever is greater
Target condition: the object must be at least 18 °F (10 °C) hotter than the sensing head
Sensing head: massive housing, 1.16 in (29.5 mm) diameter, M18 × 1 thread; up to 185 °F (85 °C) ambient
Environmental rating: IP65 (NEMA-4). See the note in the Specifications tab
Outputs: two analog outputs (0/4–20 mA, 0–5/10 V, thermocouple K, alarm); built-in USB
Power supply: 8–30 V DC / 1.2 W
At a glance
3.43 µm spectral range tuned to PE, PP, and PS thin films
95 °F to 1,112 °F (35 °C to 600 °C) with 15:1 optics
15 ms response time with 90 mK NETD
Massive 1.16"/29.5 mm housing rated to 185 °F (85 °C) ambient
Wavelength
3.43 µm for films
Polyolefin films absorb strongly at 3.43 µm, so the sensor reads the film surface instead of seeing through it to the roller or background behind.
Speed
15 ms response
A 15 ms response time with 90 mK NETD, fast enough to follow film temperature on a moving web.
Housing
Massive, M18 × 1
A 1.16 in (29.5 mm) stainless housing on an M18 × 1 thread, rated to 185 °F (85 °C) ambient.
What it is used for
Some of the use cases for the Optris CTi P3 include:
PE thin-film plastics: non-contact temperature measurement of polyethylene films.
PP thin-film plastics: non-contact temperature measurement of polypropylene films.
PS thin-film plastics: non-contact temperature measurement of polystyrene films.
Moving film webs: following temperature on a running line with a 15 ms response time.
Hot installation locations: mounting the massive-housing head in ambient temperatures up to 185 °F (85 °C).
Key features
3.43 µm spectral range: for precise temperature measurement of thin-film plastics like PE, PP, and PS.
Fast response: 15 ms (90%).
Massive housing: the sensing head is supplied in a massive housing with an M18 × 1 thread.
Two-piece design: separate sensing head and electronics box with easily accessible programming keys and a backlit LCD display.
Built-in USB interface: simple sensor setup via mobile phone or PC.
Selectable analog outputs: two outputs, each 0/4–20 mA, 0–5 V, 0–10 V, or thermocouple type K, plus an alarm output.
Optional fieldbus interfaces: EtherNet/IP, Profinet, EtherCAT, Ethernet TCP/IP with Modbus TCP, Modbus RTU, RS485, RS232, or two optically isolated relay outputs.
Three programmable I/O pins: external emissivity adjustment, ambient temperature compensation, uncommitted value, trigger (reset of hold functions), or alarm output.
Signal processing: peak hold, valley hold, and averaging, plus extended hold functions with threshold and hysteresis.
Easy sensing head exchange: heads can be exchanged within a model group by entering the Head ID into the electronics box.
Software and app: configuration through Optris CompactPlus Connect software or the IRmobile app.
Why engineers pick it
Tuned to thin-film plastics. The 3.43 µm spectral range targets PE, PP, and PS films, where a broadband sensor would read through the film rather than measuring it.
Fast. A 15 ms response time with 90 mK NETD and ± 0.45 °F (± 0.25 K) repeatability.
Simple setup. Programming keys, a backlit LCD display, and USB setup via phone or PC.
Flexible integration. Two analog outputs, three programmable I/O pins, and optional industrial Ethernet, fieldbus, and relay interfaces.
Frequently asked questions
Can I use the CTi P3 as a 2-wire sensor?
No. Do not connect a supply voltage to the analog outputs, as this will destroy the output. The CTi P3 is not a 2-wire sensor. If you need a two-wire device, review the Optris CSmicro series instead.
What distance-to-spot size ratio is correct for my application?
The size of the measuring object and the thermometer's optical resolution determine the maximum distance between the sensing head and the object. To prevent measuring errors, the object should fill the field of view of the optics. The spot should always be the same size as the object or smaller.
Can I shorten the cable between the sensing head and the electronics box?
On the CTi P3 the sensing head cable can be shortened by a maximum of 9.8 ft (3 m).
How do I exchange the sensing head?
Heads are connected and calibrated at the factory, with the Head ID already entered. Any exchange of sensing heads and electronics is possible within a given model group. Every head carries a specific Head ID, printed on the head cable and engraved on the sensing head. This calibration code must be stored in the electronics box for correct temperature measurement and sensor functionality.
How can I improve the noise amplitude of the sensor?
Do not move the head cable during measurement. Use shielded cables only and ground the sensor shield. Avoid ground loops and related signal interference in industrial environments. It may be necessary to interrupt the ground connections inside the electronics box by switching the internal jumper to another position. Review the manual before doing so.
Configuring and scaling
Select the cable length on this page and use Request Quote to order. Cable lengths are 9.8 ft (3 m) standard, 26.2 ft (8 m), or 49.2 ft (15 m). Contact W5 for anything the selector doesn't cover, such as optional digital interfaces and relay outputs.
Scope of supply
CTi P3 with a 9.8 ft (3 m) cable, mounting nut, and quick start guide.
Two conditions worth checking first
The published accuracy applies above 122 °F (50 °C), even though the measuring range starts at 95 °F (35 °C), and the object must be at least 18 °F (10 °C) hotter than the sensing head. Both matter if your film runs near the bottom of the range or the head sits in a warm location. Contact W5 if your process falls into that band.
A note on close-focus optics
No close-focus or CF lens option is offered on the CTi P3. If you need a small spot at short range, contact W5 to discuss alternatives.
Get the CTi P3 specified and supplied
W5 Engineering supplies Optris infrared temperature measurement products. We match the sensor to your film material, process temperature, target size, and working distance, then specify the cable length and any fieldbus interface you need. Contact us with your application details and the ambient temperature at the mounting point, and we will return a configuration recommendation and quote.
Optris - CTi P3 : Compact Two-piece Industrial Infrared P3 Pyrometer for Thin Film Plastic
