Fans; Power Supply Unit (Psu) - Indicators, Switches, And Connectors - Motorola DIMETRA MTS 2 Installation, Configuration And Basic Service Manual

MTS 2 and MTS 4 Installation, Configuration and Basic Service Manual
The PSU stops charging the backup battery on the following conditions:
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*When a temperature sensor is connected to the battery and PSU. If the battery sensor is not
connected the battery will be charged with 54.24 ±1% VDC as if the battery temperature was 25
°C. The battery temperature monitored through CAN Bus will show 100 °C.

Fans

The PSU supplies fans, which are located in the fan trays under the module cage. For more
information on fans, see
fans is 12 to 24 VDC and the output current is 1 A for each fan. Three fan connector outputs shall
supply three fan trays with two fans connected in parallel in each fan tray.
Fan supply output voltage can be automatically regulated as a function of PSU internal (ambient)
temperature and its output power. Fan supply output voltage can also be controlled by the CAN Bus in 7
steps from 24 V to 12 V. The highest value wins - automatic control versus CAN control.
At an ambient temperature below -10 °C the fans are stopped and restarted again at -8 °C. The fan
supply ramps up to 24 V output for a few seconds in all start up situations.
Power Supply Unit (PSU) - Indicators, Switches, and
Connectors
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This section lists and describes:
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Figure 11-2
6802800U74-N September 2009
Internal PSU temperature: > 100 °C
Battery Temperature*: < -12.5 °C
Battery Temperature*: > 53 °C
Chapter 12, "Cooling
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"PSU Indicators (LEDs)"
"PSU Switch"
"PSU Connectors"
shows the positions of indicators, switches and connectors on the PSU front panel.
Fans". The PSU DC output voltage dedicated for
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Fans
11-5