U8S
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5.6. Cooling the U8S
The U8S has an on-board DC-DC converter to convert the 12V input to 5.2V, which is required
to operate the downstream USB ports. As no DC-DC converter is 100% efficient, heat is
generated and, in some instances, forced cooling may be required to keep the operating
temperature of the U8S below 60°C.
The safety features of the product include an over-temperature feature that causes the board
to temporarily shut down when the board temperature exceeds 65°C board temperature can
be measured using a temperature sensor placed at the location shown in the diagram below.
Temperature can also be monitored via our API, LiveViewer App and the command line
interface. When measuring temperature to determine if forced cooling is required, the
temperature should be measured whilst the U8S is under
full load and at the highest ambient operating temperature.
Forced cooling may be required if the board is operated inside an enclosure and/or at high
ambient temperatures. We recommend using a fan placed above or beside the DC-DC
converter and monitoring fan flow-rate and position to ensure the unit remains below 60°C.
The DC-DC converter is the small PCB mounted orthogonally to the main U8S printed circuit
board.
The fan connections are made using 2/3 pins of the 4-pin connections. Two types of connection
are possible:
a) Constant speed – Connect the fan using two wires to +5Vdc and GND
b) Variable speed – connect the fan using +5Vdc, GND and PWM
