The drive unit
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Figure 4-19: Charging contacts polarity
4.3.5
The transformer
The transformer is prescribed by ThyssenKrupp:
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Article number 07.72.40.100
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Voltage in 220BAC 50/60Hz
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Voltage out 33VDC
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Power out 82.5 Watt
4.3.6
Fuses
The transformer is fitted with an automatic fuse. In case of overload the fuse ( a bi-metallic fuse) gets hot and
switches the transformer automatically. Once the transformer has cooled down it will automatically switch on again.
The control board is equipped with two resettable polyfuses. One fuse to protect the battery charging circuit and one
fuse to protect the supply for the various printed circuit boards.
The batteries are protected by a 30A fuse. This is fitted in the wiring from the battery to the control board and is not
part of the electronics.
4.3.7
Measurement points and led indications
For service purposes there are a number of test points available on the control board:
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DC supplies
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Battery voltage
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Charger input voltage
A green led on the control board indicates that the microcontroller is alive are correct. The led will dim if the system
is in stand-by mode.
The control board is equipped with a reset button to reset the microprocessor.
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