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Description and non-contractual illustrations in this document are given as an indication only.
ERCO & GENER reserves the right to make any modifications.
5.2.2 Technical constraints in lorry
It is highly recommended to
NOT
connect the modem supply directly the battery but instead to the circuit
breaker. Otherwise the modem may be damaged when the lorry is starting and the circuit breaker is closed.
In this case the ground of the lorry and the ground of the battery will be connected together via the modem
as shown in the diagram below:
GenPro 18e
Example of a
forbidden
electrical connexion (risk of damage to the modem)
The diagram above shows an electrical connexion which may damage the modem because its ground is
connected directly to the earth of the battery.
In this example, when the circuit breaker is closed, the current flows via the modem and the electrical circuits
in the lorry (dash-board for example). When the lorry’s starter motor is used it could result in the cables and
or the modem being damaged or destroyed.
The internal circuits of the modem are not designed to withstand the high currents associated with starter
motors.