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Multi Channel Thermocouple Data Loggers

4 Channel Thermocouple Data Logger (with Bluetooth)

Product Code: HH-521BT

(192.00 exc. VAT)
(185.00 exc. VAT)
(180.00 exc. VAT)
Easy to use, high accuracy, hand-held thermocouple data logger with four input channels and Bluetooth capability. Powered by batteries or USB.

Simply connect your thermocouple sensor(s) using a miniature flat-pinned plug. Selectable between thermocouple inputs K, J, T, N, E, R and S.

All four input channels are shown on the screen at once, identified as T1, T2, T3 and T4, with the ability to also show T1-T2 differential.

The data logger can store/recall up to 100 manual data logging 'spot' readings, or over 32,000 readings per channel in automatic logging mode. An alarm on channel 1 (T1) can be configured to audibly alert if the temperature exceeds a high or low limit.

Install the free Windows software on a PC and connect to the data logger using the supplied USB cable or wirelessly via Bluetooth (for wireless connections the PC must be Bluetooth capable). The software can retrieve historical logged data or perform real-time logging on-screen; data can be printed, graphed and exported in .csv, .txt or .ghf format (.ghf format for use only with the software). Exported files can be loaded into the software or other applications such as Microsoft® Excel.

With the free "Testlink" app installed on an iOS or Android device, historical or real-time data can be viewed wirelessly, saved and shared, removing the need to connect the data logger to a computer.

• 4 thermocouple input channels (accepts types K, J, T, N, E, R, S)
• Bluetooth capability with free iOS/Android app
• 32,000 points per channel; 100 sets of manually saved data
• High accuracy, fast response, selectable sampling rate
• T1, T2, T3, T4 and T1-T2
• °C / °F selectable
• Backlit LCD display, integrated tilt stand
• Min, Max, Avg, Hold, Mem, Recall, Offset, Setup, Temp. Unit, Alarm (T1)
• Battery or USB powered, auto power off / low battery indicator
• Free Windows software for real-time logging or historical data retrieval
• Supplied with carry case, instruction manual, batteries, software, micro USB cable and Bluetooth adapter

Technical Details
Input (miniature plug) *4 x Thermocouple



K-200°C to +1372°C (-328°F to +2501°F)
J-200°C to +1000°C (-328°F to +1832°F)
T-200°C to +400°C (-328°F to +752°F)
N-200°C to +1300°C (-328°F to +2372°F)
E-200°C to +750°C (-328°F to +1382°F)
R, S0°C to +1767°C (+32°F to +3212°F)
Accuracy **K, J, T, N, E±(0.1% of reading +0.7°C) ±(0.1% of reading +1.3°F)
Below -100°C (-148°F):
±(0.5% of reading +0.7°C) ±(0.5% of reading +1.3°F)
R, S±(0.2% of reading +1.4°C) ±(0.2% of reading +2.5°F)
ResolutionK, J, T, N, E0.1°C < 600°C / 0.1°F < 1000°F, 1°C ≥ 600°C / 1°F ≥ 1000°F
R, S0.2°C < 600°C / 0.5°F < 1000°F, 1°C ≥ 600°C / 1°F ≥ 1000°F
Temperature Coefficient0.01% of reading +0.05°C (0.0028°F) per °C [<18°C (64°F) or > 28°C (82°F)]
Manual Logging Capacity100 readings
Auto Logging Capacity32,000 readings per channel
Sample Rate2 times per second default (00:01 - 60:59 programmable)
DisplayBacklit LCD display
FunctionsMin, Max, Avg, Hold, Mem, Recall, Offset, Setup, Temp. Unit, Alarm (T1), Auto Off, Low Battery
Operating Temperature0°C to +50°C (+32°F to +122°F)
Operating Humidity10 to 90 %RH (no condensing)
Storage Temperature-20°C to +60°C (-4°F to +140°F)
Storage Humidity10 to 75 %RH
Power4 x 1.5V AAA batteries or via USB
Battery Life (alkaline)Bluetooth OFF: Approximately 120 hours
Bluetooth ON: Approximately 30 hours
Dimensions187mm (L) x 75mm (W) x 29mm (H)
Weight~317g with batteries/Bluetooth adapter
~267g without batteries/Bluetooth adapter

* Thermocouple sensor(s) not supplied - available separately

** Accuracy stated is for indicator only. The thermocouple sensor innacuracy should also be considered

Data Logger Programmable Features

Data Logger Programmable Features

  • • Turn Bluetooth on/off
  • • Set Thermocouple Type (K,J,T,N,E,R,S)
  • • Set sample rate seconds (00:01 - 60:59)
  • • Set offset (all 4 channels)
  • • Set alarm (T1 only)
  • • Set T1-T2 on/off
  • • Set auto power off time (10 min, 30 min, 1, 2, 4, 8 hours)
  • • Set system clock (date/time)
Free PC Software Features

Free PC Software Features

  • • Connect data logger via USB or Bluetooth (Bluetooth device required on PC)
  • • View data as text or graph
  • • Perform real time logging
  • • Load manually saved data from data logger
  • • Save/load real time data (export as .csv, .txt, .ghf)
  • • PANEL simulates data logger and displays real time data
  • • Control data logger using the PANEL display
  • • Set sample rate
Bluetooth TestLink App Features

Bluetooth "TestLink" App Features

Real Time Reading
  • • Shows real time temperature data for all four channels
  • • Change temperature display to C or F
  • • Set high/low alarm on all four channels (visual/audible alerts on app)
Real Time Graph
  • • Shows real time temperature data for all four channels in graph form
  • • Set sample rate (1 - 60 seconds)
  • • Record data to data logger (saved as .csv file)
Data Download
  • • Download data from data logger previously recorded manually via data logger or PC software
  • • View data as a graph or text
  • • Share text data via email, message, Dropbox or iCloud (hardware dependent)
File Open
  • • Open real time data recorded through the app using Real Time Graph
  • • View data as a graph or text
  • • Share text data via email, message, Dropbox or iCloud (hardware dependent)
Free HH-521BT Software

Free HH-521BT Software

Free Windows software for real-time logging or historical data retrieval.
Compatible with Microsoft Windows 7, 8, 10 (32-bit and 64-bit).

Note: remove old software before installing a new version.

Free HH-521BT iOS App (TestLink)

Free HH-521BT iOS App (TestLink)

Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch

Free HH-521BT Android App (TestLink)

Free HH-521BT Android App (TestLink)

Requires Android 4.3 or later

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