Danaher Motion SuperDrive ACS24 Series, Руководство пользователя

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26.04.2005 Installation
3.9 I
NRUSH CURRENT LIMITING RESISTANCE
CAUTION
♦
The battery wiring to AC SuperDrives must include a suitable
PTC (positive temperature coefficient) resistance or other
provisions for limiting inrush current to the drive’s filter
capacitors during power up. Failure to limit inrush current
may damage the drive.
During a cold start (when battery power is first applied via the disconnect switch), resistance in
parallel with the main contactor provides limited current for charging the AC SuperDrive filter
capacitors prior to energizing the main contactor. The resistance is comprised of a standard
resistor in series with a PTC (Positive Temperature Coefficient) resistor. The PTC resistance
serves to reduce current flow in the circuit in the event of a short circuit fault. In normal operation
the filter capacitors have fully charged before the ohmic value of the PTC resistance changes
significantly.
A diode in series with the PTC resistance prevents the energy stored in the SuperDrive’s internal
capacitors from powering the truck controller when the start key is switched off. See
Figure 11 .
The configuration shown in Figure 15 is typically used for Inrush Current Limiting for one (1) up to
four (4) AC Superdrive.
Figure 15. Recommended Inrush Current Limiting Circuit.
3.10 M
AIN CONTACTOR
The main contactor functions as both a power distribution component and key component of the
AC SuperDrive safety and protective interlocks circuit. The main contactor is energized when the
AC SuperDrives and the motors they control are ready and available to execute motion. When,
as the result of some error/fault condition motion is not permitted, the main contactor is
deenergized. During vehicle power-up the main contactor allows direct application of battery
power to the AC SuperDrive only after filter capacitors in each AC SuperDrive have charged.
The following power output verses DC Input current relationship may be used when sizing a main
contactor and associated cabling:
I
DC_IN
(DC Input current) =
power output kVA
VBATT VDC
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User's Guide 1.0 Item No.
89Y05120A
27