Rockwell Automation 284G ArmorStart - User Manual - Manual (Page 196)

10-8 Troubleshooting
DB Undercurrent Fault
The DB1 compares each current measurement against the Min
Current Level. The Min Current Level = Min DB Voltage Level/Max
DB Resistance. If 5 consecutive samples are below the Min Current
Level and the DB is ON, then a fault is recorded. This fault is
intended to notify the user if the DB resistance is higher than
expected. This fault is disabled when parameter 182 (DB Resistor
Sel) is “Disabled.
Troubleshooting – DB monitor has measured a DB current lower
than expected. Turn off all power to unit. Allow at least 3 minutes for
capacitors to discharge. Disconnect DB resistor from ArmorStart
control module. Caution- DB resistor may still be hot. Measure DB
resistor value at the connector with an ohmmeter. DB resistor value
should be within the limits defined in Table 10.4. If DB resistance
value is within limits, replace control module. If not, replace DB
resistor.
DB Switch Fault
A DB Switch fault is issued when continuous DB resistor current is
detected when the Drive Bus Voltage level is less than the DB Voltage
Level. If 5 consecutive samples of Drive Bus Voltage less than DB
Level is detected along with continuous DB resistor current flow, then
a shorted DB IGBT fault (DB Switch) is recorded.
It is the user’s responsibility to provide an input power contactor to
each ArmorStart with a drive. The user must write logic to control
(open) the input contactor to the ArmorStart in the event of a DB
Switch Fault. The Instruction Literature provides information on how
to connect the input contactor, and how to implement the logic.
Troubleshooting – Attempt to reset the fault by removing all power
to the unit and restarting. If the fault persists, replace control module.
DB Open Fault
A DB Open fault is issued when Bus Voltage is greater than the DB
Voltage Level, and no DB resistor current has been detected. If 5
consecutive samples of Drive Bus Voltage greater than the DB Level
is detected along with no DB resistor current flow, then an open DB
fault is recorded. This fault is intended to notify the customer of an
open DB resistor, or open wire. The fault is disabled when the DB
Resistor Setup parameter (82) is “Disabled”.
Troubleshooting – DB monitor expected to see current flow and
measured none. Likely cause is an open DB resistor, loose DB
resistor connector, or open wire in DB cable. Check DB cable
connector for tightness. If problem persists, remove DB resistor cable
connector from unit and check DB resistance. If DB resistor is open,
replace DB resistor. Otherwise replace control module.