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ONE20 Help

ELD Hardware Overview


The ONE20 F-ELD is a PT30 ELD. The PT30 is an Electronic Logging Device (ELD) that supports the implementation of the Federal Motor Carrier Safety Administration (FMCSA) Hours Of Service (HOS) rules. The ELD connects with the vehicle it is supposed to monitor using the diagnostic port interface. The diagnostics port provides data using the J1939 protocol running at 250 or 500 kbps. The diagnostic port also supports an always on power source that powers the ELD.   

External Interface

The PT30 uses a single external interface. The interface is a 10-pin connector Molex Micro-Fit 3.0™ P/N 43650-1012. The mating connector is the Molex 0436451000. Pacific Track has approved the substitution of the Molex connector with other brands that have met a series of tests conducted internally. 


The pinout of the connector is specified in this table: 

PIN Function Details/Range
1 +V +8 to +30 V
2 GND  
5 J1708 N  
6 J1708 P  
7 UART RX (to PT30) +3.3V input compatible 5V
8 UART TX (from PT30) +3.3V output
9 IGNITION +8 to 30V
10 RELAY OUT Open-drain, 5 Amps max


The PT30 includes one RED and one GREEN LED. The LEDs are visible through a single light pipe on the side of the enclosure. 


This table summarizes the functionality of the RED LED:

LED State Meaning

GPS power management engaged

GPS is turned off

GPS backup clock is ON

Blinking GPS is in acquisition mode
On GPS signal is locked

Note: The GPS goes into power management mode when the PT30 detects that the vehicle is not moving. The GPS is periodically turned on to refresh the lock. 

Green LED

The following table summarizes the functionality of the GREEN LED.

LED State Meaning
Off Device is not plugged in
Short Blink

Device is powered

Vehicle bus not detected

Fast Blink

Bus activity detected

Device is registering

On Device is registered on the vehicle bus

Note: The GPS goes into power management mode when the PT30 detects that the vehicle is not moving. 

Power Supply

The PT30 is powered with the following internal circuitry. 

The circuit provides the following benefit:

  • Protected against reversed polarity with diode D (40V, 3A)
  • Protected against over current with the 500mA resettable fuse PF
  • Filtered against noise present on the power line with capacitor C
  • Protected against the overvoltage/overshoot present in the automotive environment with the Transient Voltage Suppressor TVS which has a peak power dissipation of 1500W

The circuit has been tested to meet the requirements of ISO 16750-2. 

Temperature Range

Components Range

All the components not listed in have an operating temperature range of -40°C to +85°C or better. The only exceptions are the two LEDs that have a low temperature range of -30°C. 

Critical Components

The table below lists all the critical components. 

Part Number Manufacturer Function Temperature Range
MCP2562T-E/SN Microchip IC TXRX CAN -40°C ~ 125°C
SN65176BDR TI IC 1/1 Transceiver Half RS422, RS485 -40°C ~ 105°C
NRF51822-QFAC Nordic Semiconductors IC BLE 256KB FLASH 32KB RAM -25°C ~ 75°C
STM32F103RCT6 STMicroelectronics IC MCU 32BIT 256KB FLASH 48K RAM 40°C ~ 105°C (TA)

GNSS Module

Module Details

The PT30 includes a u-blox MAX-8C module. The MAX-8C module is a single global navigation satellite system (GNSS) receivers that can receive and track either GPS or GLONASS signals. In the PT30, only the GPS constellation is enabled. The MAX-8 modules support reception of SBAS broadcast signals. These systems supplement GPS data with additional regional or wide area GPS augmentation data. The system broadcasts augmentation data via satellite and this information can be used by GNSS receivers to improve the resulting precision. SBAS satellites can also be used as additional signals for ranging (navigation), further enhancing availability. The following SBAS types are supported: WAAS, EGNOS, and MSAS. For applications within North America (initial market for the PT30), the MAX-8C will use the WAAS constellation to improve the accuracy of the position. 

Module Quality

The u-blox 8 modules use GNSS chips qualified according to AEC-Q100 and are manufactured in ISO/TS 16949 certified sites. Qualification tests are performed as stipulated in the ISO16750 standard: “Road vehicles – Environmental conditions and testing for electrical and electronic equipment.” 

Module Performance


Cold Start 30 s
Hot Start 1 s


Tracking & Navigation -164 dBm
Reacquisition -159 dBm
Cold Start -147 dBm
Hot Start -156 dBm

Module Operating Conditions

Per u-blox:

  • Storage temperature: -40° C to 105° C
  • Operating temperature: -40° C to 85° C

Module Substitution

Pacific Track has approved using the MAX-M8-C module in replacement of the MAX-8C. The MAX-M8C is electrically and mechanically identical to the MAX-8C, but it supports receiving and decoding multiple GNSS constellations simultaneously.   

Module Implementation

The GNSS circuitry inside the PT30 includes the following components: 

  • A patch antenna, 25 mm2 with 4.5 dBic gain
  • A low noise amplifier (LNA) with a gain of 21.0dB and a noise figure of 0.65dB
  • The MAX-8C module

The actual implementation of the GNSS subsystem has been reviewed by u-blox and their suggestions have been included in the design. 

Flash Reliability

Wear Leveling

The flash device used is in the PT30 is specified for more than 100,000 erase/program cycles and 20-year data retention. If a file system (such as FAT16 or FAT32) is installed on such a device, some memory blocks might be erased and programmed more often than others. This, for example, may apply to the blocks containing the File Allocation Table (FAT).

To increase the reliability of the product, the PT30 file system implements wear leveling. Wear leveling spreads the writes to the flash chip evenly over the entire area. This extends the life time of the chip. 


The file system also implements journaling. Journaling protects the file system data structures and prevents them from being corrupted. Even if a write is interrupted by something like a power loss.



The PT30 is designed and will be tested to be compliant under 47 CFR FCC Part 15.247. The product must meet the limits set by the following individual test: 

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