Rockwell Automation SMC-Flex, User Manual

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8-4 Diagnostics
Fault Definitions
Table 8.B shows the fault definitions for the SMC-Flex.
➀
Phase loss, overvoltage, and undervoltage protection are disabled during braking operation.
➁
Jam detection and underload protection are disabled during slow speed and braking operation.
Table 8.B Fault Definitions
Fault Description
Line Loss F1, F2, F3 The SMC-Flex can determine if a line connection has been lost, and will indicate this accordingly.
Shorted SCR Shorted SCRs will be detected and starting will be prohibited by the SMC-Flex.
Open Gate Open gate indicates that an abnormal condition that causes faulty firing (e.g., open SCR gate) has been sensed during
the start sequence. The SMC-Flex controller will attempt to start the motor a total of three times before the controller
shuts down.
Power Pole PTC and SCR
Overtemperature The power pole temperature in each phase is monitored. If the temperature rises above the predetermined level, the
unit will fault to protect the power pole. A reset can be performed once the temperature falls below this level.
Motor PTC A motor PTC can be connected to terminals 23 and 24. If the PTC parameter is enabled and the PTC trips, the
SMC-Flex will trip and indicate a Motor PTC fault.
Open Bypass Power pole bypass contacts are monitored for proper operation. In the event that a contact closure is not sensed, the
SMC-Flex will indicate an Open Bypass fault.
No Load The SMC-Flex can determine if a load connection has been lost, and No Load fault will be indicated.
Line Unbalance ➀ Voltage unbalance is detected by monitoring the three phase supply voltages. The formula used to calculate the
percentage voltage unbalance is as follows:
V
u
= 100 (V
d
/ V
a
)
V
u
: Percent voltage unbalance
V
d
: Maximum voltage deviation from the average voltage
V
a
: Average voltage
The controller will shut down when the calculated voltage unbalance reaches the user-programmed trip percentages.
Overvoltage and
Undervoltage Protection
➀
Overvoltage and undervoltage protection are user-defined as a percentage of the programmed line voltage. The
SMC-Flex controller continuously monitors the three supply phases. The calculated average is then compared to the
programmed trip level.
Underload
➁
Underload protection is available for undercurrent monitoring. The controller will shut down when the motor current
drops below the trip level. This trip level, a percentage of the motor’s full load current rating, can be programmed.
Overload Protection Overload protection is enabled in the Motor Protection group by programming the:
•
Overload class
• Overload reset
• Motor FLC
• Service factor
• Refer to Chapter 5 for more information on Motor Protection.
Phase Reversal Phase reversal is indicated when the incoming power to the SMC-Flex controller is in any sequence other than ABC.
This pre-start protective feature can be disabled.
Coms Loss The SMC-Flex controller disables control through the DPI communication port as the factory default. To enable control,
the Logic Mask found in the Communication programming group must be set to “4.”
If a Bulletin 20-HIM LCD Human interface module is disconnected from the SMC-Flex controller when control is
enabled, a Comm Fault will occur.
Other settings could also cause this fault, see Table 7.D.
Network Network faults are faults generated on the network external to the SMC-Flex, and are annunciated on the LCD display.
Ground Fault Ground faults are based on feedback from the user supplied 825 CT (5…480 A devices only) detecting ground fault
currents. Ground fault parameters of level and time delay must be programmed for proper operation.
Excess Starts/Hour Excess starts/hour is displayed when the number of starts in a one hour period exceeds the value programmed.
Power Loss Power loss indicates that an input power phase is not present. The controller’s LCD display will identify the missing
phase.
If all three phases are absent when a start command is issued, the LCD will display “Starting” without motor rotation.
Line Loss F41, F42, F43 During expected SCR gate periods, the power pole voltage and currents are monitored. If the SCR conduction is
discontinuous, a fault is indicated.