Servicing, Circuit breaker cba and fuses – Rockwell Automation 1608 HC-DySC User Manual, 200 A User Manual
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Rockwell Automation Publication 1608P-UM004A-EN-P - September 2013
Chapter 6
Maintenance
Servicing
Before attempting any servicing that requires opening the HC-DySC doors first
put the system into
Bypass (maintenance) mode as described in
Circuit Breaker CBI, Safety Interlocks and Stored Energy
shows the arrangement of circuit breakers CBI and CBA and
of the bypass switch contacts INPUT, OUTPUT and BYPASS. If the cabinet
doors are opened while the HC-DySC is operating the circuit breaker CBI will
be automatically opened and load power will be interrupted unless the bypass
switch is first put into the BYPASS position. Doors should be kept locked to
avoid this situation.
The HC-DySC includes a fast-discharge circuit to quickly dissipate stored
energy when the circuit breaker CBI is opened. Placing the bypass switch in
BYPASS will automatically open CBI. CBI may be operated automatically by the
door interlock switches or other protection devices. CBI can also be operated
manually.
If the upstream power is interrupted before CBI is opened the fast-discharge
circuit will not be triggered. In that case wait at least 30 minutes before opening
the HC-DySC doors to avoid exposure to charged capacitors. High voltage
remains on capacitors if the red LED indicators above the power module
capacitor banks are lighted.
Circuit Breaker CBA and Fuses
Fast-acting fuses are included to protect the HC-DySC in the event of a load
short circuit condition. If the system is found to be offline and the display shows
an “Open Fuse” alarm then a load short circuit may have occurred. Verify no load
short circuit condition exists before placing the bypass switch into the BYPASS
position. Circuit breaker CBA will limit current through the bypass switch in
case of a load short circuit condition while in the BYPASS mode. If there is no
output voltage present and the display is off, it is an indication that either the
CBA circuit breaker has opened or an upstream protection device has opened.
ATTENTION: Service must be performed by qualified personnel only.
WARNING: The HC-DySC is interlocked. Opening cabinet doors while the
system is in operation will result in loss of power to protected loads, unless the
bypass switch is in the BYPASS position.