Troubleshooting
S611 Soft Starter MN03901003E—January 2012 www.eaton.com 9
S611 Fault Codes, continued
Note
Shorted SCRs are the most common mode of SCR failure. With power completely removed from the unit, measure the resistance of each pole, line to load.
If the resistance is near zero (less than 5 ohms), it is most likely that the SCR is shorted. Resistance of a serviceable SCR is approximately 10k ohms.
Resistance typically moves to a lower value as the SCR ages. This feature may be disabled (not recommended).
Code Fault Condition Solution
18 Shorted SCR
• SCR is shorted
• Internal bypass contactor welded shut
• No load on the SCRs when START
command is issued
• Test resistance of each phase
• Contact EatonCare for service
19 Instantaneous Overcurrent • Excessive starting current
• Excessive load
• Reduce starting load
• Increase soft starter capacity (be sure model ratings
can handle current demands)
20 Overload • Motor overloaded for an extended
period of time
• Thermal memory is over 100%
• Reduce the motor’s load
• Verify the
Overld Trip FLA and/or Ovrld Trip Class for
proper adjustment
•
Note: Exceeding nameplate ratings will shorten
equipment life
• Fault during motor start: Verify system is not
exceeding the specified maximum starts per hour
• Increase the initial torque and/or reduce ramp time
to bring the motor up to speed faster
• Increase Trip Class setting (5–30 maximum) and/or
reduce ramp time setting
21 Mains AC Voltage Loss • Fuses or breaker open
• Disconnect open
• Replace fuses, close disconnect, or reset breaker
22 Under Voltage • Incoming AC line voltage below trip
threshold
• Incorrect mains supply voltage
• Connect to correct supply voltage
• Verify that mains voltage is within acceptable values
• Verify
Motor Rated Voltage in the Operation mode is
set to the correct value
23 Over Voltage • Incoming AC line voltage above trip
threshold
• Incorrect mains supply voltage
• Connect to correct supply voltage
• Verify
Motor Rated Voltage in the Operation mode is
set to correct value
24 Phase Reversal • Incoming line phase rotation sequence
opposite of device setting
• Single-phase missing and/or open fuse
or breaker
• Set Phase Sequence to match incoming sequence OR
• Exchange two incoming mains phases
• Verify that all circuit breakers are closed or fuses are
serviceable
25 Start Stall • Motor not at rated RPM at end of start
ramp time and/or current is in excess of
trip threshold
• Bypass contactors not closed at the end
of the start time (start current low/ramp
time short)
• Lengthen Soft Start Time and/or increase Initial
Torque
in the Operations mode
• Increase trip threshold
• Loads that are heavily loaded (high inertia) during a
start such as fans will often need an initial torque
setting much greater than the factory default
• Set
Kick Start parameters
27 SCR Overcurrent • Excessive SCR current during the start
ramp
• Only active when Stall Fault is disabled
• Increase Soft Start Time and/or Initial Torque
parameters in
Operation mode
• Reduce starting load
• Verify S611 is properly rated for current
28 Under Load • Loss of motor load
• Trip threshold set too high
• Excessive current fluctuation during
operation
• Inspect for failed motor coupling or pump cavitation
• Reduce trip threshold
• Increase trip delay time to ride through transient load
changes
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