General considerations for system design
GVI Product Manual: Frames C, D & E
52
192-300300N1 GVI Frames C, D & E 2019-9
•
Motor and battery cables must be thermally dimensioned to match the power of the
motor controller and the motor. The European standard EN1175-1 (A 3.7) requires that
the battery connector parts shall withstand 90 ºC. It is recommended as a minimum that
all cables are chosen to withstand this temperature.
•
All high voltage cables shall be shielded.
•
The cable area shall be selected to match the 1 hour rating of the application, EN1175-
1 (5.10.2). As a rule of thumb, use current density of 3 A/mm2 to get an indication of
necessary cable area.
Cable area in mm
2
=
(
1h current
)
�
3 A
mm
2
�
12.3 Electrostatic discharge
•
Connect frame of motors to the frame of the vehicle.
•
To consider at customer’s production: If a separate battery on a cart is used, connect
the frame of the cart to the frame of the truck to avoid different charge levels on truck
frame and battery. Different levels may damage the unit or motor.
•
Depending on the units connected to the bus, it may be necessary to have an external
10 M
Ω
resistor between battery minus and vehicle frame to prevent build-up of
excessive static electricity between frame and battery.
12.4 Start-up & Turn-off Sequences
•
The electrolytic capacitor bank of the motor controller unit must be charged. The time
required to charge the capacitor is monitored and an error is set if it takes longer than
the set limit for charge time-out (default value is 10 seconds).
If an external pre-charge circuit is used, required charging time and number of units in
parallel should be taken into account when dimensioning the circuit. DC bus
capacitance values for the GVI models are found in Table 14.
•
Check how the truck controller handles normal turn on/off of the units in the system. No
error codes should be saved during normal sequences.
