Rockwell Automation Allen-Bradley PowerFlex 700AFE, Руководство пользователя

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Rockwell Automation Publication 20Y-UM001F-EN-P - April 2017 81
AFE in IP21 Rittal Enclosure – Installation/Wiring Chapter 2
Precharging the AFE
This section contains important information about AFE precharging.
Introduction
An AFE in the IP21 Rittal enclosure contains an internal precharging circuit.
The precharging unit is used to charge the DC bus capacitors. The charging
time depends on the capacitance of the intermediate circuit and the resistance
of the charging resistors. Table 20 shows the technical specifications for the
precharge in the AFE enclosure. For correct operation of the precharging
circuit, the input circuit breaker and the precharging circuit contactor must be
controlled by the AFE.
Table 20 - Total DC Bus Capacitance Limits for Precharging Circuit of AFE in IP21 Rittal
Enclosure
Important Guidelines
Read and understand these guidelines:
• If drives
without
internal precharge are used and a disconnect is
installed between the input of the drive and the DC bus, you must use
an external precharge circuit between the disconnect and the DC input
of the drive.
• If drives
with
internal precharge are used with a disconnect switch to the
common bus, you must connect an auxiliary contact on the disconnect
to a digital input of the drive. The corresponding input must be set to
the ‘Precharge Enable’ option. This option provides the proper
precharge interlock, guarding against possible damage to the drive when
connected to a common DC bus.
• The precharge status of the AFE must be interlocked with the
connected drives, such that the drives are disabled (not running) when
the AFE is in a precharge state.
Frame Size Resistance Capacitance, min
(1)
(1) The minimum capacitance is built into the AFE.
Capacitance, max
(2)
(2) The maximum capacitance is the capacitance of the AFE plus the external capacitance.
10 2 x 20 Ω 9900 μF 70,000 μF
13 2 x 11 Ω 29,700 μF 128,000 μF
ATTENTION: If the maximum capacitance is exceeded, component damage
in AFE occurs.