InteliSENS® SLM-i4


InteliSENS® SLM-i4


Proton Products InteliSENS® SLM-i4 Series non-contact, unidirectional speed and length gauges provide extremely accurate speed and length measurements for metals industry applications. They are available with extended stand-off distances and greater depth-of-field than the standard InteliSENS® SL Series gauges, which allows them to be used to measure very high-temperature objects such as in hot-rolling processes.

Applications requiring a precise cut-to-length process benefit from the non-slip and highly accurate laser measurement technique which reduces scrap increases uptime, and improves material yield by eliminating product “Give Away” or “Short Length” claims.

Focused on connectivity the SLM-i4 Smart Sensor with 32bit communications comes preloaded with Profibus, Profinet, and Ethernet Industrial Protocol for your PLC connection. Modbus, OPC-UA, RS232, RS485, and WiFi round out a wide range of digital communications for your Industry 4.0 Solution.

  • No-Slip, No Wear, No Marking
  • Unidirectional speed and length measurement.
  • UKAS-traceable calibration; accuracy better than 0.05% and repeatability better than 0.02%.
  • Rugged industrial design for use in harsh factory environments.
  • Available fitted with industry-standard communications interfaces for easy integration with PLCs and production line equipment.
  • Excellent value with low cost of ownership.
  • Harsh environment enclosures are available from Proton Products on request.


  SLM 6060-i4 SLM 100100-i4 SLM 120120-i4 SLM 200200-i4
Stand Off Distance 600mm
Depth of Field 60mm
Minimum Speed 0.3 m/min
1.0 ft/min
0.4 m/min
1.3 ft/min

0.6 m/min
2.0 ft/min

0.9 m/min
3.0 ft/min

Maximum Speed 3000 m/min
9842 ft/min
6000 m/min
19685 ft/min
10000 m/min
32808 ft/min
10000 m/min
32808 ft/min


Factory Calibrated to better than 0.05%.
Repeatability of 0.02%


Maximum Acceleration Rate of 1000m/s2 (3280ft/s2)
Measurement Rate Up to 25,000/sec


Speed Measurement selectable m/min, ft/min, yd/min
Length Measurement selectable m, ft, inch, yd


Normal (Continuous Length), Batch Length

Object Detection

Automatic Detection and Object Present


Pulse Outputs x 3

Default Output 5vdc or User Input to 24vdc
Max Maximum Frequency 1MHz Pulse Rate Selectable - Pulse/Meter or
Meter/Pulse Configurable as 6 x Single End or 3 Quadrature or 3 Differential.
Non Isolated from Gauge Head, Opto Isolated from the PSU-BOB i4

Logic Input x 2

Maximum Input Voltage 24Vdc
2 x Fixed logic Inputs - Laser Enable and Shutter Enable
3 x Selectable logic Inputs - Reverse Direction, Length Reset, Display Hold, Speed Hold, Total Length Reset, End of Reel

Relay Outputs x 3

Maximum Voltage 30Vdc, Current 100mA.
N-Channel MOSFET pull-down (for connection to user supplied onto isolated relay)
1 x Fixed Logic Output - Shutter Status
3 x Selectable logic outputs - Gauge Ok, Measuring Speed, Preset Length 1, Preset
Length 2, Good Readings Low, Object Detected, Gauge Hot.

Relay Outputs x 3

RS232 MODBUS RTU, PROTON ASCII code or Label Printer
USB using RS232 - USB Converter Cable
RS485 MODBUS RTU, PROTON ASCII code (Not available with PROFIBUS)

Relay Outputs x 3

Connects to Proton Products CDi4 Display

Relay Outputs x 3

Ethernet selectable between OPC-UA and Modbus

Relay Outputs x 3

Connect to a PLC using PROFIBUS, PROFINET, or EtherNet I/P, data update rate up to 500/sec. Flexible Data Configuration, Big Endian, Little Endian

i-BUS x 1

Connect to a PC or Mobile Device using WiFi 2.4G and use the Proton Products Gauge App available for iOS and Android. Ideal for gauge configuration and diagnostics

Laser Doppler

Class 3B Visible Laser.
Wavelength 650 - 670 nm, typically 658 nm with a beam diameter of 3mm (0.12”)
Total emitted power 80mW. Power Density at Stand Off Distance 1120mW/cm2 

Laser Doppler

Electrical and Operating Requirements

Power Supply
18 - 30 Vdc 

Power Consumption
20 Watts 

Operating Temperature
5°C - 40°C (41°F-104°F)*

*See Accessories for High-Temperature protection options

Environmental Protection
IP 67

Size and Weight


220mm (8.7”)

130mm (5.1”)

78mm (3.1”)

3kg (6.6lbs)

Industry 4.0

More than 200 Data Words are available to communicate with your Industry 4.0 Solution. Data Words are divided into distinct function groups to make it easy to select the ones you want.
Gauge ID Data Words Model Number, Serial Number, Firmware APP version, Firmware Core Version, Firmware Date
Calibration Data Last Calibration Date, Days Since Last Calibration, Total Run Time, Calibration Alarm
Validation Data Words SNR, Signal Amplitude, Good Readings, FFT Amplitude
Wired Network Info IP Address, Netmask, Gateway
WiFi Network Info IP Address, Netmask, Gateway, SSID
Measurement Data Instant Speed, Average Speed, Batch Length, Total Length
Diagnostic Data Laser Temperature, APD Temperature, Laser ON/OFF Cycles, Laser Power