Rockwell Automation Allen-Bradley SMC-50 User manual

SMC™-50 Fully Solid-State Smart Motor Controller
Bulletin 150
User Manual

Rockwell Automation Publication 150-UM011A-EN-P - July 2011 213
Chapter 10
Troubleshooting
Introduction
For safety of maintenance personnel as well as others who might be exposed to
electrical hazards associated with maintenance activities, follow the local safety
related work practices (e.g., NFPA 70E, Part II in the United States).
Maintenance personnel must be trained in the safety practices, procedures, and
requirements that pertain to their respective job assignments.
The following flowchart is provided to aid in quick troubleshooting.
SHOCK HAZARD: Hazardous voltage is present in the motor circuit even
when the SMC-50 is off. To avoid shock hazard, disconnect main power
before working on the controller, motor, and control devices (e.g.,
Start-Stop push buttons). Procedures that require parts of the equipment
to be energized during troubleshooting, testing, etc., must be performed
by properly qualified personne using appropriate local safety work
practices and precautionary measures.
ATTENTION: Disconnect the controller from the motor before measuring
insulation resistance (IR) of the motor windings. Voltages used for
insulation resistance testing can cause SCR failure. Do not make any
measurements on the controller with an IR tester (megger).
NOTE: The time it takes for the motor to come up to speed may be more or less than
the time programmed. This depends upon the motor and load characteristics.
NOTE: Depending upon the application, the braking options (SMB Smart Motor
Braking and Slow Speed) may cause some vibration or noise during the
stopping cycle. To minimize vibration or noise, lower the braking current
adjustment. If this is a concern in your application, please consult the factory
before implementing the braking options.

214 Rockwell Automation Publication 150-UM011A-EN-P - July 2011
Chapter 10 Troubleshooting
Figure 88 - Troubleshooting Flowchart
Define nature
of
trouble.
YES
NO
See Table 108 See Table 109 See Table 110 See Table 112
See Table 111
Fault Displayed?
Motor rotates but
does not accelerate
to full speed.
Motor stops
while running.
Miscellaneous
situations.
Motor will not start.
There is no output
voltage to the motor.
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions
Line Loss
(with phase indication) 1, 2, 3 Prestart &
Running
•High impedance line connection
•Missing supply phase
•Motor not connected properly
•Incoming 3-phase voltage instability
•Check for line and load loose connections.
•Check for open line (e.g., blown fuse).
•Check for open line lead(s).
•Verify power quality.
•Disable this fault/alarm feature.
Shorted SCR
(with phase Indication) 4, 5, 6 In All Modes
•Shorted power module. •Check for shorted SCR, perform a resistance check
(refer to Power Module Check section), or replace
power module if necessary.
Open Gate
(with phase indication) 7, 8, 9 Start or Stop
•Open gate circuitry
•Loose gate lead
•Perform a resistance check (refer to Power Module
Check section), replace power module if necessary.
•Remove control module from the power section and
check gate lead connections (TB5, TB6, and TB 7)
are firmly seated to the control module.
•Disable this fault/alarm feature.
SCR Overtemp or
PTC Power Pole 10 or 60 In All Modes
•Controller ventilation blocked
•Controller duty cycle exceeded
•Fan failure
•Ambient temperature limit exceeded
•Failed thermistor
•Check for proper controller ventilation.
•Check application-appropriate duty cycle.
•Wait for controller to cool or provide external
cooling if ambient temperature is high.
•Check for fan operation. Replace fan, if necessary.
•Replace power module or control module as
needed.
No Load or Open Load
(with Phase Indication)
14,
15,
16,
17
Prestart Only
•Loss of load side power wiring with
phase indication (15=A, 17=C)
•Start command cycled unexpectedly
with motor rotating
•Check all load side power connections.
•Check motor windings (megger).
Voltage Unbalance or
Current Imbalance 18 or 42 Running
•Power line unbalance is greater than
the programmed value
•The delay time programmed is too
short for the application
•Check the power system and correct if necessary or
change the programmed value.
•Extend the delay time to match the application
requirements.
•Disable this fault/alarm feature.

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Troubleshooting Chapter 10
Overvoltage 19 Running
•Power line grid voltage is greater
than the programmed value
•Abnormal voltage regulation
•The parameter settings &/or delay
time programmed are not suited for
the application
•Check the power system and correct if necessary.
NOTE: If the power source is a backup generator,
check the stability of the generator voltage
regulator. Replace if necessary.
•Modify the parameter &/or extend the delay time to
match the application requirements.
•Disable this fault/alarm feature.
Undervoltage 20 Running
•Power line grid voltage is less than
the programmed value
•Abnormal voltage regulation
•The parameter settings & or delay
time programmed are not suited for
the application
•Check the power system and correct if necessary.
NOTE: If the power source is a backup generator,
check the stability of the generator voltage
regulator. Replace if necessary.
•Modify the parameter &/or extend the delay time to
match the application requirements.
•Disable this fault/alarm feature.
Overload 21 Running
•Motor overloaded
•Overload parameters are not
matched to the motor
•Check motor overload condition.
•Check programmed values for overload class and
motor FLC; verify current draw of the motor.
•Disable this fault/alarm feature. ➌
Underload 22 Running
•Broken motor shaft, belt, greating,
etc.
•Pump cavitation
•Programmed setting incorrect for
application
•Check machine drive components and loading.
•Check pump system.
•Repair or replace motor.
•Check programmed settings.
•Disable this fault/alarm feature.
Jam 23 Running
•Motor current has exceeded the
user programmed jam level for the
programmed time
•Correct source of jam or excessive loading.
•Check programmed time value.
•Disable this fault/alarm feature.
Stall 24 Running
•The motor did not reach full speed
by the end of the programmed ramp
time
•Incorrect programmed setting
•Check pump system, machine drive components,
and loading; repair or replace motor, if necessary.
•Check programmed settings.
•Disable this fault/alarm feature.
Phase Reversal 25 Prestart Only
•The controller is not detecting
incoming supply voltage in the
expected ABC sequence
•Check power wiring and correct, if necessary.
•Disable this fault/alarm feature.
Exp Removed x026 ➊In All Modes
•Expansion module is loose or
removed
•Expansion module is defective
•Reseat or replace the expansion module connector
to the control module and tighten module screws.
•Replace defective module.
Exp Incompat x027 ➊In All Modes
•Expansion module is inserted into an
incompatible control module port
number
•Controller firmware is not
compatible with the expansion
module
•Expansion module is defective
•Insert the expansion module into a compatible
contorl module port.
•Update the control module firmware
•Replace defective module.
Expansion x028 ➊In All Modes
•Expansion module is loose or
removed
•Expansion module is defective
•Expansion module is inserted into an
incompatible control module port
number
•Controller firmware is not
compatible with the expansion
module
•Reseat and/or replace loose/removed module and
tighten module screws.
•Replace defective expansion module.
•Update control module firmware.
Starts per Hour 29 Starting
•The number of starts within the last
hour has exceeded the programmed
value
•Programmed setting is incorrect for
the application
•Wait for the hour to expire, then restart the motor.
•Reduce the actual number of starts per hour or
increase the programmed start time (if allowed by
the application) and controller thermal limits.
•Turn off this fault/alarm feature.
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions

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Chapter 10 Troubleshooting
CT Loss
A, B, or C
30,
31, or
32
In All Modes
•Loose CT cable connection between
the power section and the control
module
•Phase A (F30), B (F31), or C (F32)
current transformer feedback circuit
has failed
•Option Module 150-SM2 with
external CT operation (Fault Code
7030, 8030)
•Remove the control module from the power section;
verify connectors TB2 (A), TB3 (B), and TB4 (C) are
firmly seated to the control module.
•Replace the control module and/or the power
section.
•Inspect the CT sensor cables for loose connections;
check CTs for damage; repair/replace CTs if
necessary; replace 150-SM2 option module if
necessary.
Hall ID 33 In All Modes
•Loose cables betweeen the
controller and power section.
•Incompatible power section
installed with the controller
•Remove the control module from the power section;
verify connectors TB2 (A), TB3 (B), and TB4 (C) are
firmly seated to the control module.
•Check the power section and replace, if necessary.
NVS Error 34 In All Modes
•Controller memory corrupted
•Option module error (Fault Code
7034, 8034, or 9034)
•Modify a parameter or load parameter defaults
(preferred) and reload the customer-specific
parameters.
•Check the option module sensor cables.
•Replace the option module.
Future Use 35 NA NA NA
V24 Loss 36 In All Modes
•Loose connection at Control
Terminals 1 (+L1) and 2 (-L2)
•Excessive load on internal 24V
supply
•Low line voltage condition
•Check the control power and verify it is within the
specification; check the line connections and
grounding to the SMC-50 control terminals.
•Replace the control module.
V Control Loss 37 In All Modes
•Loose connection at Control
Terminals 1 (+L1) and 2 (-L2)
•Low line voltage condition
•Check the control power and verify it is within the
specification; check the connections and grounding
to the SMC-50 control terminals.
•Replace the control module.
TB Input
1, 2, 3 & 4
38,
39,
40, &
41
In All Modes
•The condition to generate the TB
Input fault is satisfied
•Terminal wiring configuration or
fault N.O./N.C. configuration of
input is incorrect
•Clear the fault condition.
•Rewire and/or reconfigure the input.
Und Pwr Real ➋43 Running
•Abnormally reduced real (MW)
power draw by the motor possibly
due to broken mechanical
connection (belt, gears, etc.)
between motor and load
•Pump cavitation
•Programmed setting is incorrect for
the application
•Repair/replace the condition causing the reduced
real power load.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Ovr Pwr Real ➋44 Running
•Abnormally high real (KW) power
draw by the motor
•Programmed setting is incorrect for
the application
•Repair/replace the condition causing the high KW
power draw.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Un Pwr Reac+ ➋45 Running
•Abnormally reduced reactive
(+MVAR) power produced by the
motor
•Programmed setting is incorrect for
the application
•Repair/replace the condition causing the reduced
+MVAR power draw.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Ov Pwr Reac+ ➋46 Running
•Abnormally high reactive (+MVAR)
power produced by the motor
•Programmed settings are incorrect
for the application
•Repair/replace the condition causing the high
+MVAR power draw.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions

Rockwell Automation Publication 150-UM011A-EN-P - July 2011 217
Troubleshooting Chapter 10
Und Pwr App ➋47 Running
•Abnormally reduced apparent (MVA)
power draw by the motor
•Programmed settings are incorrect
for the application
•Repair/replace the condition causing the reduced
+MVA power draw.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Ovr Pwr App ➋48 Running
•Abnormally high apparent (MVA)
power draw by the motor
•Programmed settings are incorrect
for the application
•Repair/replace the condition causing the high
+MVA power draw.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Frequency 49 Running
•Speed control regulation system of
the generator prime mover (e.g.,
diesel engine) is unable to adjust to
current load conditions or is
defective
•Abnormal power grid connections;
power generation source is
operating outside its normal
frequency limits or range
•Reduce the generator load, increase grenerator
output, replace the speed control system, or
generator.
NOTE: For a diesel generator system, Rockwell
Automation recommends it be oversized by a
factor of three for Soft Start applications.
•Contact the power company for additional
information.
•Modify the programmed fault/alarm parameters to
better suit the application.
PM Hours 50 In All Modes
•The number of hours programmed in
the PM Hours Parameter has been
reached
•Perform required maintenance and reset the PM
Hours parameter.
•Disable this fault/alarm feature.
PM Starts 51 Pre-Start
•The number of Starts programmed in
the PM Start Parameter has been
reached
•Perform required maintenance and reset the PM
Hours parameter.
•Disable this fault/alarm feature.
Power Quality
A, B, or C
52,
53, or
54
Start or Stop
•Incoming 3-phase voltage instability
or distortion
•High impedence line or load
connection
•Check supply voltage for capability to start/stop the
motor; check for loose connections on the line side
or motor side of the power wires.
•Verify and correct the input power quality issue
•Disable this fault/alarm feature.
Power Quality
THD V 55 Running
•The current mix of loads on the
power line contributing to the THD V
has exceeded the programmed THD
V level &/or time
•Check the mix of loads (what was added, what was
changed); modify the load mix if necessary.
•Change the programmed THD V level &/or delay
time.
•Disable this fault/alarm feature.
Power Quality
THD I 56 Running
•The current mix of loads on the
power line contributing to the THD I
has exceeded the programmed THD
I level &/or time
•Check the mix of loads (what was added, what was
changed); modify the load mix if necessary.
•Change the programmed THD I level &/or delay
time.
•Disable this fault/alarm feature.
Config Change 57 In All Modes •A controller parameter has been
modified
•Disable this fault/alarm feature.
Ground Fault X058 ➊Running
•The ground fault current level has
exceeded the programmed value
•The delay time is too short for the
application
NOTE: An optional 150-SM2
Ground Fault PTC Module is
required for this fault.
•Check the power system and motor; correct if
necessary.
•Check the programmed ground fault levels to match
application requirements; modify if necessary.
•Extend the delay time to match the application
requirements.
•Disable this fault/alarm feature.
Motor PTC X059 ➊In All Modes
•Motor ventilation is blocked.
•Motor duty cycle is exceeded
•PTC open or shorted
NOTE: An optional 150-SM2
Ground Fault PTC Module is
required for this fault.
•Check for proper ventilation.
•Check application duty cycle.
•Wait for motor to cool or provide external cooling,
then check resistance of PTC.
•Disable this fault/alarm feature.
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions

218 Rockwell Automation Publication 150-UM011A-EN-P - July 2011
Chapter 10 Troubleshooting
I/O Config 61 Pre-Start
•The configuration of the control I/O
does not meet the system rules as
defined in Chapter 4, Configuration
Functions on page 120
•Modify the control I/O configuration to meet the
established rules.
Test Fault 62 In All Modes
•The SMC-50’s Push to Reset/Hold to
Test push button was pressed for
more than three seconds, but less
than ten
•The SMC-50’s Push to Reset/Hold to
Test push button is stuck or
damaged
•To reset the Test fault, press the Push to Reset/Hold
to Test push button for less than two seconds.
NOTE: Only use the Push to Reset push button
when absolutely necessary.
•Attempt to dislodge the push button or replace the
control module if necessary.
Und PF Lag 63 In All Modes
•A lagging PF is abnormally under the
typical value; less inductance or
more capacitance has been
introduced to the power line
•A programmed setting or time value
is incorrect for the application
•Determine the cause of the reduced Lagging PF.
•Modify the porgrammed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Und PF Lead 64 Running
•A leading PF is abnormally under the
typical value; less inductance or
more capacitance has been
introduced to the power line
•A programmed setting or time value
is incorrect for the application
•Determine the cause of the reduced Leading PF
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Ovr PF Lag 65 Running
•A lagging PF is abnormally over the
typical value; more inductance or
less capacitance has been
introduced to the power line
•A programmed setting or time value
is incorrect for the application
•Determine the cause of the Over PF Lagging
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
Ovr PF Lead 66 Running
•A leading PF is abnormally under the
typical value; less inductance or
more capacitance has been
introduced to the power line
•A programmed setting or time value
is incorrect for the application
•Determine the cause of the Over PF Leading.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
-MVAR Over ➋67 Running
•Abnormally high reactive (-MVAR)
power consumed by the motor
•Programmed settings are incorrect
for the application
•Repair/replace the condition causing the high
-MVAR.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
-MVAR Under ➋68 Running
•Abnormally reduced reactive
(-MVAR) power consumed by the
motor
•Programmed settings are incorrect
for the application
•Repair/replace the condition causing the reduced
-MVAR.
•Modify the programmed fault/alarm parameters to
better suit the application.
•Disable the fault/alarm feature.
RTC Battery Low 69 Pre-Start
•Battery reading is below the
acceptable level to potentially
maintain the real time clock and
calendar
•Replace battery (CR2032) as soon as possible.
Locked Rotor 70 In All Modes
•Motor has stalled; rotor is not
turning
•Check motor and load for binding or jammed
conditions
•Parameters are not adequately configured for the
application. Review and adjust.
•Disable the fault/alarm feature.
Start 71 Starting •A start event (command) has
occurred. This is not a fault. •NA
Slow Speed 72 Slow Speed •A slow speed event (command) has
occurred. This is not a fault. •NA
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions

Rockwell Automation Publication 150-UM011A-EN-P - July 2011 219
Troubleshooting Chapter 10
Stop Option 73 Stop Option •A stop option event (command) has
occurred. This is not a fault. •NA
Coast 74 Coast •A coast-to-stop event (command)
has occurred. This is not a fault. •NA
Clear Fault 75 Faulted
•A clear fault event (command) has
occured. This does not generate a
fault.
•NA
Fault 76 Faulted •A fault event (command) has
occured. This is not a fault.
•NA
Param Change 77 Stopped
•A change to one of the controller
parameters has occured. This is not
a fault.
•NA
Reserved 78-99 NA NA NA
System Faults 100-199 In All Modes
•There is an issue with the control
module wiring
•The control module is defective
•Review the control module wiring. Ensure the
ground terminal is secure and connected to the
system’s earth ground. Ensure an RC
snubber/suppressor is connected to all inductive
loads in the control circuit. Refer to input wiring.
•Replace the control module.
➊"X" indicates a port number in which the expansion module resides in the SMC-50.
➋ The Real, Reactive, and Apparent Power faults/alarms are best suited to provide indication of an abnormal running operation of the motor or system which
another parameter (e.g., Underload, Overload, Jam, Stall, etc.) does not provide. To understand what is an abnormal running operation, a "normal" or "typical"
value, usually established during system startup, needs to be determined by the user.
➌If controller based motor overload is disabled, external motor overload protection should be used.
Table 110 - Fault Display Explanation
Display Fault Code Fault Enabled Possible Causes Possible Solutions

220 Rockwell Automation Publication 150-UM011A-EN-P - July 2011
Chapter 10 Troubleshooting
Table 111 - Motor Will Not Start — No Output Voltage to the Motor
Table 112 - Motor Rotates but Does Not Accelerate to Full Speed
Display Possible Cause Possible Solutions
Fault displayed •See fault description •See Table 110 addressing fault
conditions
HIM display is blank •Failed HIM
•Control voltage is absent
•Failed control module
•HIM connection is loose
•Replace HIM
•Check control wiring and correct
if necessary
•Replace control module
•Cycle control power
•Check HIM connection
Stopped
0.0 Amps
•Pilot devices
•SMC Enable input is open at
terminal 9
•Configured or wired input
terminals are not wired
correctly
•Start-Stop control has not
been enabled for the human
interface module
•Control voltage
•Failed control module
•Check wiring
•Check wiring
•Check wiring; follow the
instructions on page 193 to
enable control capability.
•Check control voltage
•Replace control module
Starting •One or more power phases are
missing
•Isolation contactor (if used) is
not picking up
•Check power system
•Check that the SMC-50 Aux.
relay output controlling the
Isolation Contactor is configured
to "Normal".
•Check the Isolation Contactor for
proper operation
Display Possible Cause Possible Solutions
Fault displayed •See fault description •See Table 110 addressing fault
conditions
Starting •Mechanical problems
Inadequate Current Limit
setting
•Failed control module
•Check for binding or external loading
and correct
•Check motor
•Adjust the Current Limit Level to a
higher setting
•Replace control module

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Troubleshooting Chapter 10
Table 113 - Motor Stops While Running
Display Possible Cause Possible Solutions
Fault displayed •See fault description •See addressing fault conditions
HIM display is blank •Failed HIM
•Control voltage is absent
•Failed control module
•HIM connection is loose
•Replace HIM
•Check control wiring and correct
if necessary
•Replace control module
•Check HIM connection
Stopped
0.0 Amps
•Pilot devices
•Failed control module
•Check control wiring and correct
if necessary
•Replace control module
Starting •One or more power phases are
missing
•Failed control module
•Check power system
•Replace control module

222 Rockwell Automation Publication 150-UM011A-EN-P - July 2011
Chapter 10 Troubleshooting
Table 114 - Miscellaneous Situations
Situation Possible Cause Possible Solutions
Motor current and
voltage fluctuates
•Motor
•Erratic Load
•Verify type of motor as a standard squirrel
cage induction motor
•Check load conditions
Erratic operation •Loose connections •Shut off all power to controller and check
for loose connections
Accelerates too fast •Starting time
•Initial torque
•Current limit setting
•Kickstart
•Increase starting time
•Lower initial torque setting
•Decrease current limit setting
•Lower kickstart time or turn off
Accelerates too
slow
•Starting time
•Initial torque
•Current limit setting
•Kickstart
•Decrease starting time
•Increase initial torque setting
•Increase current limit setting
•Increase kickstart time or turn off
Fan does not
operate ➊
•Control wiring
•Failed fan(s)
•Check control wiring and correct if necessary
•Replace fan module
Motor stops too
quickly with Soft
Stop option
•Time setting •Verify the programmed stopping time and
correct if necessary
Motor stops too
slowly with Soft
Stop option
•Stopping time setting
•Misapplication
•Verify the programmed stopping time and
correct if necessary
•The Soft Stop option is intended to extend
the stopping time for loads that stop
suddenly when power is removed from the
motor.
Fluid surges with
pumps still occur
with the Soft Stop
option
•Misapplication •Soft Stop ramps voltage down over a set
period of time. In the case of pumps, the
voltage may drop too rapidly to prevent
surges. A closed loop system such as Pump
Control would be more appropriately suited.
Motor overheats •Duty cycle •Preset Slow Speed and SMB options:
Extended operation at slow speeds reduces
motor cooling efficiency. Consult motor
manufacturer for motor limitations.
•Smart Motor Braking option: Check duty
cycle. Consult motor manufacturer for motor
limitations.
Motor short circuit •Winding fault •Identify fault and correct.
•Check for shorted SCR; replace if necessary.
•Ensure power terminals are secure.
➊Fan operation is controlled by the SMC-50 Control Module. The fan may not run in low ambient temperatire conditions. Refer
to Chapter 2, Fan Power on page 28 for additional details.

Rockwell Automation Publication 150-UM011A-EN-P - July 2011 223
Troubleshooting Chapter 10
Power Module Check
If a power module needs to be checked, use the applicable procedure that follows.
Shorted SCR Test
1. Using an ohm meter, measure the resistance between the line and load
terminals of each phase on the controller. (L1-T1, L2-T2, & L3-T3)
The resistance should be greater than 5,000 ohms. Replace the power assembly if
this reading is not reached. Refer to Appendix C for the list of
Spare/Replacement SMC-50 parts.
ATTENTION: To avoid shock hazard, disconnect main power before
working on the controller, motor, or control devices such as Start/Stop
push buttons.
ATTENTION: Make sure that wires are properly marked and
programmed parameter values are recorded.

224 Rockwell Automation Publication 150-UM011A-EN-P - July 2011
Chapter 10 Troubleshooting