Hioki Launches High-Speed Thermistor Modules U8557 and LR8537 — Fast, Multi-Channel Temperature Measurement for EV and Energy Development

Nagano, Japan, 10th March 2026 - Hioki E.E. Corporation is pleased to announce the launch of the Thermistor Module U8557 and the Wireless Thermistor Module LR8537 for the LR8450 and LR8450-01 Data Logger Series.

Designed for fast, high-density temperature measurement, these new modules enable EV, industrial, and energy sector engineers to capture multi-channel thermal behavior with a 50 ms data update interval, helping streamline evaluation from prototype development to validation and inspection.

Development Background

Thermistors are widely used in automotive, consumer electronics, and industrial equipment for temperature sensing. With the rapid adoption of battery-electric vehicles (BEVs) and hybrid electric vehicles (HEVs), thermal management has become increasingly critical to optimizing efficiency, enhancing safety, and increasing power density.

In particular, temperature control of batteries and effective cooling of batteries and motors have become key development themes. Engineers therefore need practical ways to evaluate temperature behavior using thermistors already built into systems or prototypes during development and validation. However, conventional approaches involve complex wiring, slow measurement speeds, and heavy post processing, especially as channel counts rise.

The U8557 and LR8537 were created to solve these challenges by delivering fast, scalable thermistor based temperature measurement that integrates easily into modern EV and energy related development environments.

Product Overview

The U8557 and LR8537 are 15-channel thermistor / resistance measurement modules supporting up to 200 kΩ, with a fast 50 ms data update interval and 16-bit A/D resolution.

By registering a thermistor's resistance-temperature characteristics in the LR8450 or LR8450-01, users can convert resistance values into real time temperature readings. Multiple characteristic equations can be configured, enabling support for a broad range of thermistor types commonly used in the field.

By combining multiple modules, users can measure:
• U8557: Up to 60 thermistor channels with the LR8450 Series
• LR8537: Up to 165 thermistor channels with the LR8450-01 in a wireless configuration

All channels can be updated at 50 ms intervals, more than 10× faster than typical bench-top digital multimeters (DMMs), enabling acquisition synchronized with typical BMS update cycles. This is especially effective for battery module evaluation before BMS installation, as well as for validation and inspection tasks that involve BMS behavior.

The modules can also be used alongside other LR8450/LR8450-01 modules, such as thermocouple modules, enabling a flexible temperature measurement platform that supports multiple sensor types within a single system.

Key Features

• 15 thermistor / resistance input channels per module
• Fast 50 ms data update interval
• 16-bit A/D resolution
• Resistance ranges: 2000 Ω / 20 kΩ / 200 kΩ
• Push-button type terminal blocks for easy and reliable wiring

Main Applications

• EV / HEV battery evaluation
  Temperature distribution analysis and transient thermal behavior analysis of the battery components
• BMS verification and validation
  Correlation analysis between thermistor measurements and BMS behavior
• Motor and inverter evaluation
  Temperature monitoring inside motors and during durability testing
• High-density temperature measurement on test benches
  Visualization of transient thermal behavior using high-speed, multi-channel acquisition
• Wireless temperature measurement environments (LR8537)
  Monitoring where wiring is difficult or where mobility is require

Product Lineup

Link

For more information about Hioki Thermistor Module U8557 and Wireless Thermistor Module LR8537, please visit:
U8557 product page
LR8537 product page

Contact us

For inquiries such as quotes, demonstrations, and trial usage, please use Hioki's contact form for a personalized reply from your closest or most appropriate Hioki representative.

• The information provided is current as of the date of publishing.
• Please note that prices, specifications, and other information contained in this texts are subject to change without notice.
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