Armature Overcurrent Fault
Armature current has exceeded the drive's programmed overcurrent threshold, typically indicating a motor winding short, mechanical jam, or power stage failure in the thyristor/IGBT converter. The drive protection circuit has triggered a shutdown to prevent thermal damage to the motor and power electronics.
Error Code
F60.1
Severity
Fault
Equipment
DC Drive
Manufacturer
Siemens
Drive trips immediately on startup or during acceleration, LED display shows F60.1 code
Ammeter reading exceeds 150% of rated motor current within 100-500ms of enable command
Motor hums or vibrates without rotating, indicating locked rotor condition
Thyristor/IGBT heat sink temperature rises rapidly (>70Ā°C) even at no-load condition
Control circuit LED flashes red pattern indicating fault latch, requires manual reset
DC bus voltage droops from nominal 400V to 250-300V during fault initiation
Motor armature winding short circuit or turn-to-turn insulation breakdown due to age or moisture ingress
Mechanical load jam or coupling failure causing motor to stall during acceleration
Thyristor/IGBT power stage gate drive circuit malfunction preventing proper commutation, causing shoot-through current
Faulty current sensing circuit or shunt resistor reading false high values to the comparator
Main power contactor stuck in closed position while drive is disabled, causing phantom current feedback
Motor field winding disconnection creating uncontrolled armature voltage conditions
Verify motor is mechanically free: rotate shaft manually by hand to confirm no binding or jamming; check coupling alignment and load connection
Measure DC motor armature resistance with multimeter at disconnected motor terminals - should be 0.5-2.5Ī© depending on motor size; readings below 0.2Ī© or open circuit indicate winding damage
Test thyristor/IGBT gate drive circuits using oscilloscope at converter PCB gate drive test points - verify gate pulses are symmetrical 5-15V pulses with proper 120Ā° spacing for 3-phase rectifier
Check shunt current sensor: disconnect power, measure shunt resistance (typically 10mĪ©), verify wiring continuity to sense amplifier IC, test amplifier output voltage proportional to applied test current
Inspect main power contactor coil for stuck armature: measure coil resistance (should be 800-1500Ī©), verify contactor disengages when control power is removed, check contact wear
Measure motor field circuit continuity and resistance at field terminals - typical range 50-200Ī© depending on motor class; open field indicates excitation loss
If motor test passes, replace drive control PCB or power stage module depending on gate drive fault diagnosis; order specific module per EEPROM configuration data
After repair, perform no-load acceleration test at 25% speed command, monitoring ammeter - current should remain below 50A; if trip recurs, motor winding replacement required
Safety First: Always isolate power and follow LOTO (Lockout/Tagout) procedures before working on electrical components. If unsure, contact a certified repair technician.
Get fault code alerts for Siemens equipment
Weekly repair tips, new fault codes, maintenance guides ā free.
Get Your Equipment
Back in Action ā Fast
Send us your faulty industrial electronics. Our engineers will diagnose it and provide a detailed quote within 24 hours ā with no obligation to proceed.
Free Evaluation
No obligation
48hr Turnaround
Fastest in India
6-Month Warranty
Every repair
No Fix, No Charge
Zero risk policy
Pan-India Pickup
Doorstep service