APQ E5M Low-Power Multi-Serial Embedded Industrial PC Solution for Rail Transit
In rail transit operation and maintenance systems, onboard condition monitoring is the primary data source for ensuring train safety and enabling predictive maintenance. Temperature, vibration, current, speed, and other sensors are installed onboard to collect real-time operating data from key components such as the running gear, traction motors, and braking systems. After processing by the onboard data acquisition equipment, the data is uploaded to a ground-based analysis platform to support fault warnings and equipment health management.
After multiple rounds of product evaluation and rigorous on-site validation, the customer selected the APQ E5M low-power multi-serial embedded industrial PC as the core device for its rail transit onboard sensor data acquisition system.
Customer Challenge
Concurrent Connection of Multiple Sensor Type: Each carriage needs to connect multiple types of sensors simultaneously, including temperature, vibration, current, speed, and displacement sensors. The industrial PC therefore requires ample serial-port resources and flexible switching between RS-232 and RS-485 communication protocols.
Ultra-Low Power and Fanless Design: Onboard equipment operates for long periods in enclosed carriage environments with limited heat dissipation and unavoidable dust. The device therefore needs extremely low power consumption and fanless passive cooling to avoid system downtime caused by fan failure.
Compact Size and Flexible Installation: Space inside train equipment compartments is extremely limited. The industrial PC must be compact and support multiple mounting methods, including wall mounting and VESA mounting, to fit different vehicle designs.
Wide-Temperature, Wide-Voltage, and Rugged Design: Train operating environments involve significant temperature changes and frequent vibration. The system must support an operating temperature range of -20°C to 60°C, a 12-28 VDC wide-range input, and IEC-compliant vibration and shock resistance.
APQ Solution
Six Serial Ports for Simultaneous Multi-Sensor Connectivity:The E5M provides six onboard COM ports, including two switchable RS-232/485 ports and four RS-232 ports. This rich serial configuration supports simultaneous connection of temperature, vibration, speed, current, and other serial sensors, meeting multi-source data acquisition requirements for condition monitoring of critical running-gear components. High-speed RS-232 mode supports real-time and accurate sensor data transmission.
Ultra-Low-Power Fanless Design for Enclosed Onboard Environments:The E5M is powered by an Intel® Celeron® J1900 ultra-low-power processor with a TDP of only 10 W. The system uses fanless passive cooling and contains no vulnerable moving fan components, significantly reducing the failure rate. In sealed onboard cabinets with limited heat dissipation, the fanless design avoids cooling failures caused by dust accumulation or fan damage, reduces operating noise, and lowers the load on the onboard power supply. An all-aluminum heat sink combined with a galvanized steel chassis balances thermal efficiency and structural strength.
Wide-Temperature, Wide-Voltage, and Rugged for Demanding Rail Conditions:E5M supports an operating temperature range of -20°C to 60°C and a storage temperature range of -40°C to 80°C. Its 12-28 VDC wide-range power input is compatible with the onboard power systems of different train models. The system has passed 3 Grms vibration testing and 30 G shock testing, supporting long-term stable operation in the high-frequency vibration environment of high-speed rail operation.
Compact Form Factor and Flexible Mounting for Space-Constrained Installations:The E5M measures only 293.5 mm × 149.5 mm × 54.5 mm and has a net weight of approximately 2.1 kg. It supports VESA, wall-mount, and desktop installation, enabling flexible deployment in compact onboard cabinets and saving valuable installation space.
Dual Gigabit Ethernet and Wireless Expansion for Reliable Data Upload:The E5M integrates two Intel® Gigabit Ethernet ports: one for communication with the onboard switch and train control system, and the other for data exchange with the back-end monitoring platform. A built-in Mini PCIe slot (PCIe 2.0 + USB 2.0, with a Nano SIM slot) supports optional 4G modules for real-time monitoring data upload. An M.2 Key-M slot supports SATA SSD expansion for local data caching.
Rich I/O for Multiple Peripheral Devices:The E5M provides one front USB 3.0 port and three front USB 2.0 ports, together with four rear USB 2.0 ports, for a total of eight USB interfaces. VGA and HDMI outputs support dual-display operation. The built-in 16-bit GPIO facilitates connection to various sensors and actuators. The system also supports APQ proprietary MXM expansion modules, allowing flexible addition of COM or GPIO functions for application-specific customization.
Value Achievements:
Multi-sensor integration in a single system: Six serial ports (2 × RS-232/485 + 4 × RS-232), combined with dual Gigabit Ethernet, enable direct connection of temperature, vibration, speed, current, and other sensors in the running gear. The complete data acquisition architecture can be deployed without additional expansion modules, significantly reducing the number of devices and wiring complexity inside the onboard cabinet.
Long-term reliability in enclosed environments: The 10 W ultra-low-power platform and fanless passive cooling eliminate failure risks associated with vulnerable fan components, enabling stable 24/7 data acquisition in enclosed and dusty train environments. The failure rate is significantly lower than that of conventional fan-cooled systems.
Stable operation under demanding conditions: Wide-temperature operation from -20°C to 60°C, a 12-28 VDC wide-range input, 3G vibration resistance, and 30G shock resistance ensure continuous sensor data acquisition under high-speed operation, temperature changes, and track vibration in high-speed trains and metro vehicles, providing an uninterrupted data source for predictive maintenance.
Compact deployment saves onboard space: The compact 293.5 mm × 149.5 mm × 54.5 mm form factor, together with VESA, wall-mount, and desktop installation options, enables flexible integration into onboard cabinets and frees additional space for other functional modules.
Flexible expansion for customized requirements: The Mini PCIe slot with SIM support enables 4G/Wi-Fi wireless expansion, the MXM module supports application-specific COM/GPIO expansion, and the M.2 Key-M slot allows SSD capacity expansion, meeting the varied requirements of different train models and monitoring projects.
