Northern Fridge TruckFridge TF130, Manual, Page: 6 / 47

TruckFridge Built-in User Manual
Updated 5 July 2020 Page 6
2.1.2 Electronic Control Unit (ECU)
The Electronic control unit of the compressor is a piece of electronic equipment which carries out all the controls
and electrical protection of the compressor system. Its main features include;
a) Protection of the battery with automatic turning off of the compressor when the feeding voltage reaches the
minimum threshold (cut out) typically 10 volts. The compressor will start up automatically again when the voltage
goes back to normal values (cut in). Typically 11 volts. Must always be directly connected to the battery.
b.) Thermal overload protection cut out. The compressor will shut down when temperatures exceed 125 deg F
ambient to protect the compressor from overheating. It will cut in automatically when temperatures drop below
this.
c.) Cooling fan operation will begin automatically when compressor starts and stop when compressor shuts off in
normal operation.
The main functions of the 101N0212 is to provide all controls for the BD35F-HD compressor systems including:
• Supports both 12VDC (max. 17VDC) and 24VDC (max. 31.5VDC)
• Maximum ambient temperature is 55
O
C with built-in thermal protection
• Motor / Compressor speed control
• Thermostat control (ON / OFF)
• Condenser fan control including speed setting
• Error codes
• Battery protection functions . Polarity inversion protection.
See 8.6.1 TruckFridge 101N0212 ECU 12VDC Specifications for BD35F-HD .
2.1.2.1 Replacing the ECU
The ECU can be simply removed and/or installed by removing a screw to release module for the side of the
compressor to reveal the 3-pin plug that attaches the ECU to the compressor. Follow these simple steps;
1. Disconnect all terminals (22) from the control ECU and, while doing so, mark them adequately, so as not to
connect them wrongly during reassembly. See
Figure 2.1.2.1.1
2. Unscrew the screw (23). See Figure 2.1.2.1.2 .
3. Disconnect the connector (24) from the ECU, from the compressor (25). See Figure 2.1.2.1.3
4. Replace the damaged ECU by first assembling the left hand side and afterwards press the right hand side on the
screw head on the bracket. ln this way the ECU gets locked on the bracket and is securely fastened to the
compressor.
Figure 2.1.2.1.1
Figure 2.1.2.1.2 Figure 2.1.2.1.3