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Raytek Raynger 3i Plus

Stronger, safer, smarter and handy pyrometer

  • Ensure operator safety and efficiency with ‘Red Nose’ heat-resistant warning detector and alarm
  • Transfer measurement data fast and easy to PC or smartphone, using USB or Bluetooth®
  • Ensure accurate temperature readings at longer distances with high optical resolution
  • Rugged design reduces risk of damage and service costs; withstands 1m (3.2ft) drop

Raytek® Raynger® 3i Plus is designed for use in high-temperature industrial applications, 400–3000°C (752-5432°F), such as iron and steel, metal refining, foundry and processing operations, ceramics, semiconductors, chemical and petrochemical furnaces, as well as heat treatment and power plants.

The Raytek Raynger 3i Plus high temperature handheld infrared thermometer is designed to meet process performance requirements in many industrial applications, including highly demanding hot environments in primary and secondary metal processing, as well as petrochemical and power plant operations.

The strong and rugged design of this new generation of portable pyrometers withstands a 1m (3.2ft) drop test and provides longer operational cycle for up to 24 hours when powered with rechargeable batteries.

Raytek Raynger 3i Plus laser temperature gun features intuitive user interface for easy parameter setup and enables ‘on-site’ display of data analysis and trending, as well as fast and easy data transfer to PC or smartphone using USB or Bluetooth®.

To meet the highly demanding requirements of hot industrial environments, the Raytek 3i Plus IR thermometer features high optical resolution 250:1, which ensures accurate temperature readings at longer distances. Heat resistant “Red Nose” warning detector ensures operator safety and efficiency. Dual laser and scope sighting, visible even against “red hot” backgrounds, make this IR thermometer a perfect choice for hot temperature applications.

Key Features:

  • Read temperature ranges from 400 to 3000ºC (752 to 5432ºF)
  • Ambient operating temperatures: 0 to 50ºC (32 to 120ºF)
  • Dual laser and scope sighting options for fast and simple target aiming
  • High optical resolution: 250:1 to ensure accurate temperature readings at longer distances
  • Red Dot sighting technology for accurate targeting against “red hot” backgrounds
  • “Red Nose” heat resistant warning-detector and alarm
  • Data storage: up to 4,900 units with location, date, and time stamp
  • Bluetooth® wireless technology for communication with a mobile device
  • Documenting personal computer (PC) software

Technical Specifications

Model Number 3i-1M 3i-2M
Temperature Range 700 to 3000 ºC
(1292 to 5432 ºF)
400 to 2000 ºC
(752 to 3632 ºF)
Spectral Response 1.0 μm 1.6 μm
System Accuracy ±0.5 % of reading +1 ºC (2ºF) for <2700 ºC (4892 ºF)
± 2% of reading for >2700°C (4892°F)
Repeatability ±0.3 % of reading ±1 ºC (2ºF)
Response Time 40 mSec
Optical Resolution (D:S) 250:1
Emissivity 0.10 – 1.00
Operating Temperature 0 to 50 ºC (32 to 120 ºF)
Storage Temperature -20 to 60 ºC (-4 to 140 ºF) without batteries
Relative Humidity 10 to 90 %, RH noncondensing @ 30 ºC (86 ºF)
Dimensions /Weight Laser Models: 218 x 172 x 74 mm/700 g
(8.5 x 6.7 x 2.9 in /1.5 lb)
Scope Models: 218 x 222 x 74 mm/950 g
(8.5 x 8.7 x 2.9 in /2.0 lb)
Power Single cell Lithium-ion, 3.6 V, 2500 mAh or via USB 2.0
Battery Life (Lithion-Ion) 24 hours
Laser Laser beam for targeting (On/Off) (EN60825 Class 2, FDA Class II)
Temperature Display ºC or ºF (selectable)
Signal Processing MAX, MIN, DIF, AVG Temperatures
Audible Alarms Target temperature/Ambient temperature/Low battery
Data Logging Up to 4,900 data points
Digital Outputs USB 2.0, optional Bluetooth® 4.0** (USA/Canada: Bluetooth and USB standard)
Additional features Backlit LCD, Locking Trigger, Tripod Mounting, Reflected Energy Compensation


Raytek® Raynger 3i Plus are portable IR thermometers designed for high temperature applications. They cover a temperature range of 400 – 3000 ºC (752 – 5432 ºF) (depending on the model). Superior Distance-to-Spot (D:S) ratio allows users to measure high temperature targets from longer distances, ensuring accurate temperature readings and operator safety.

  • Metals Processing: foundry, steel and metal refining
  • Semiconductor production
  • Ceramics
  • Chemical and petrochemical furnaces


Each Raytek Raynger 3i Plus model comes with the list of accessories listed below:

  • Carrying case
  • CD with software for real-time graphic temperature display and data download, and operator’s manual (PDF format)
  • Lithium-ion battery, 2.5 Ah
  • Mini USB port adapter (100 – 240 VAC 50/60 Hz)
  • Mini USB-to-DC jack converter for charging battery separately
  • Computer cable with USB-to-Mini USB, 1.5 m (4.9 ft)


Product Literature:
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