Electric Motor Testing And Analysis

Electric Motor Repair & Rewind Services | AC/DC Motors | Colorado

Electric Motor Repair & Rewind

Expert Repairs - Precision Rewinding - Factory Quality

Professional electric motor repair and rewinding services for AC and DC motors. From fractional HP to 500+ HP, all brands, all types. Modern equipment, experienced technicians, and 1-year warranty on all work.

✓ All Motor Types ✓ 3-7 Day Turnaround ✓ Rush Service Available ✓ 1-Year Warranty ✓ 50+ Years Experience

Why Repair Instead of Replace?

💰 Major Cost Savings Motor repair typically costs 30-50% less than buying new. A $5,000 replacement motor can often be repaired for $1,500-2,500. For large motors (100+ HP), savings can exceed $20,000.

Many motors fail prematurely from problems that are easily repairable - bearing failure, winding insulation breakdown, rotor issues. These motors have decades of useful life remaining if properly repaired. Replacement should be the last option, not the first.

💵 Repair vs. Replace Cost Comparison

Motor Size New Motor Cost Typical Repair Cost Your Savings
5 HP $800-1,200 $400-600 $400-600 (50%)
25 HP $2,500-3,500 $1,000-1,800 $1,200-2,000 (50%)
50 HP $4,500-6,500 $1,800-3,000 $2,500-3,500 (50%)
100 HP $8,000-12,000 $3,000-5,500 $4,500-7,000 (50%)
250 HP $20,000-30,000 $7,000-12,000 $10,000-18,000 (50%)

Plus: Repaired motors often last 15-20 years with proper maintenance. You're not just saving money today - you're getting decades more service.

Additional Advantages of Repair:

  • Faster Than Ordering: Most repairs completed in 3-7 days vs. weeks for new motor delivery.
  • Perfect Fit: Your repaired motor drops right back in. No mounting modifications needed.
  • Environmentally Responsible: Reduces waste and preserves resources.
  • Tax Benefits: Repairs are typically fully deductible in year incurred vs. depreciation schedule.
  • Preserves Rare Motors: Obsolete or special motors that can't be replaced must be repaired.

Motor Types We Repair & Rewind

We service all motor types and brands - if it has windings, we can rewind it:

AC Induction Motors

Types:

  • Single-phase (1/4 HP - 10 HP)
  • Three-phase (1/2 HP - 500 HP)
  • TEFC (Totally Enclosed Fan Cooled)
  • ODP (Open Drip Proof)
  • TENV (Totally Enclosed Non-Ventilated)

Common Repairs: Rewind, bearing replacement, rotor repair, shaft machining

💥

Explosion-Proof Motors

Classes: Class I Div 1 & 2, Class II, Class III

Groups: C, D, E, F, G

Specialized rewind procedures maintain UL/CSA listings. Proper clearances, flameproof joints, and approved materials.

🔨

Severe Duty Motors

Applications:

  • Mining & aggregate
  • Sawmills
  • Washdown environments
  • High vibration
  • Inverter duty

Built to withstand harsh conditions with heavier construction and better insulation systems.

🔄

DC Motors

Types:

  • Shunt wound
  • Series wound
  • Compound wound
  • Permanent magnet DC
  • Brushless DC (BLDC)

Services: Armature rewind, field coil rewind, commutator service, brush replacement

🎯

Brake Motors

AC motors with integrated electromagnetic brakes for instant stopping.

Services: Motor rewind, brake adjustment, brake coil replacement, spring replacement, friction disc service

🌍

High Voltage Motors

Voltages: 2300V, 4000V, 4160V, 6900V, 13,200V

Specialized insulation systems (VPI, resin-rich), surge testing, and high-pot testing. Form-wound coils for larger motors.

🌀

Wound Rotor Motors

Slip-ring motors for variable speed or high starting torque applications.

Services: Stator rewind, rotor rewind, slip ring service, brush holder repair, carbon brush replacement

⚙️

Gearmotor Units

Motors with integrated gearboxes.

Services: Motor repair/rewind, gearbox inspection, oil change, seal replacement, gear inspection, complete unit testing

💡 Don't See Your Motor Type? We handle specialty motors not listed here: submersible motors, elevator motors, traction motors, servo motors, stepper motors, hermetic motors. Call (720) 626-9805 to discuss your specific motor.

Our Complete Repair Process

Every motor repair follows our proven 10-step process to ensure quality results:

1

Inspection & Diagnosis

Thorough examination to identify all problems, not just symptoms.

  • Visual inspection for obvious damage
  • Insulation resistance test (megger)
  • Continuity testing of all windings
  • Bearing condition assessment
  • Shaft runout measurement
  • Frame condition check
  • Nameplate verification
  • Photograph all damage
  • Document findings on inspection report
2

Written Quote & Approval

Detailed quote with all recommended work clearly explained.

  • Itemized pricing for each repair
  • Explanation of problems found
  • Repair vs. replace recommendation
  • Estimated completion time
  • Alternative options if applicable
  • No work begins until you approve
3

Disassembly & Parts Removal

Careful disassembly to preserve reusable components.

  • Remove all external components (junction box, conduit fittings, mounting hardware)
  • Mark end bell positions for proper reassembly
  • Remove bearings using proper pullers
  • Extract rotor carefully to avoid damage
  • Remove old windings if rewind needed
  • Clean and inspect all parts
  • Identify parts needing replacement
4

Stator Core Preparation

Prepare stator for new windings if rewind required.

  • Burn-out or Chemical Strip: Remove old windings (chemical stripping preferred for better insulation preservation)
  • Core Testing: Verify core integrity with core loss tester
  • Slot Cleaning: Remove all old varnish and insulation residue
  • Inspection: Check for damaged laminations, corrosion, loose core
  • Repair: Address any core damage before rewinding
5

Precision Rewinding

Wind new coils to exact OEM specifications.

  • Winding Data: Use original winding data or calculate from motor parameters
  • Wire Selection: Correct gauge magnet wire, insulation class (Class F or H typical)
  • Slot Insulation: Install appropriate slot liners
  • Coil Winding: Wind coils using computer-controlled winding machine for consistency
  • Coil Installation: Insert coils into stator slots
  • Wedge Installation: Secure coils with proper wedges
  • Lead Connections: Wye or delta configuration per nameplate
  • Lead Support: Proper lacing and bracing
6

Varnish Treatment (VPI)

Vacuum Pressure Impregnation for superior insulation.

  • Pre-heat: Remove moisture from windings
  • Vacuum Stage: Remove air from between turns
  • Varnish Flood: Flood winding with insulating varnish under vacuum
  • Pressure Stage: Force varnish deep into winding
  • Bake: Cure varnish at controlled temperature
  • Result: Monolithic winding with excellent moisture resistance and mechanical strength
7

Rotor Service

Inspect and repair rotor assembly.

  • Squirrel Cage Rotors: Check for broken bars, inspect end rings, test for core problems
  • Wound Rotors: Rewind if needed, service slip rings, check connections
  • Shaft Inspection: Check for wear, scoring, bending
  • Shaft Repair: Machine or repair as needed, build up worn areas with metalizing
  • Key/Keyway: Inspect and repair
  • Dynamic Balance: Balance rotor to ISO standards (typically G2.5 or G6.3)
8

Frame & Component Reconditioning

Restore frame and associated parts.

  • Bearing housing inspection and repair
  • Bearing fit verification (proper press fit critical)
  • Frame straightening if needed
  • Mounting holes/threads repaired
  • Sandblast and paint frame
  • Fan cleaning or replacement
  • Fan cover repair
  • Junction box recondition
9

Assembly & Testing

Reassemble motor and verify performance.

  • Bearing Installation: Install new bearings with proper heat/press methods
  • Reassembly: Install rotor, align end bells, torque all fasteners per spec
  • Electrical Testing:
    • Insulation resistance (megger): Verify >100 megohms typically
    • Surge test: Identify turn-to-turn faults
    • Hi-pot test: Verify insulation integrity at 2x voltage + 1000V
    • Continuity: Check all phases balanced
  • No-Load Run Test: Run motor without load, check current draw, noise, vibration, temperature
  • Load Test: Apply load if possible, verify performance matches nameplate
10

Final Inspection & Documentation

Quality check and provide complete records.

  • Final visual inspection
  • Verify all tests passed
  • Create new nameplate if original damaged
  • Rotation direction verification and marking
  • Touch-up paint as needed
  • Package for shipment/pickup
  • Documentation Provided:
    • Test report with all measurements
    • Before/after photos
    • Parts replaced list
    • Warranty certificate
    • Maintenance recommendations
✓ Quality Control at Every Step Our multi-step testing process ensures your motor leaves our shop in excellent condition. We don't just repair motors - we restore them to like-new performance.

Common Motor Failure Causes

Understanding why motors fail helps prevent repeat failures:

35%

Bearing Failure

Causes: Over-greasing, under-greasing, misalignment, contamination, wrong bearing type, excessive radial/axial load

Prevention: Proper lubrication schedule, laser alignment, proper coupling selection, vibration monitoring

30%

Winding Insulation Failure

Causes: Overheating (overload, poor ventilation, phase loss), moisture contamination, voltage spikes, age degradation

Prevention: Proper ventilation, surge protection, moisture seals, load monitoring, VFD filters

12%

Rotor Problems

Causes: Broken rotor bars, damaged end rings, excessive starting cycles, mechanical impact, poor casting quality

Prevention: Reduce start frequency, soft starters, proper motor sizing, avoid mechanical shock

10%

Shaft & Mechanical

Causes: Shaft bending, keyway damage, shaft wear, loose rotor, bearing failure cascade

Prevention: Proper alignment, avoid side loads, correct coupling type, proper mounting

8%

Contamination

Causes: Dust ingress, moisture, chemical exposure, oil/grease on windings

Prevention: Proper enclosure type (TEFC vs ODP), environmental seals, regular cleaning

5%

Other Causes

Electrical supply problems (voltage imbalance, harmonics), improper installation, manufacturing defects, operating outside design parameters

⚠️ Root Cause Analysis Included We don't just fix the symptom - we identify and address the root cause. If your motor failed from bearing problems, we check alignment, lubrication practices, and loading to prevent recurrence.

Repair Turnaround Times

Service Type Standard Turnaround Rush Service
Rewind Only (fractional - 25 HP) 3-5 days 24-48 hours
Rewind Only (25-100 HP) 5-7 days 2-3 days
Rewind Only (100-500 HP) 7-10 days 3-5 days
Complete Rebuild (rewind + bearings + shaft) 5-10 days 3-5 days
Bearing Replacement Only 1-2 days Same day
Testing & Evaluation Only 1-2 days Same day
Explosion-Proof Rewind 7-14 days 4-7 days
DC Motor Rewind (armature + field) 7-10 days 3-5 days

Rush Service Premium: 50-100% surcharge depending on urgency. Available 24/7 for critical equipment.

💡 Expedite Options Can't wait for standard turnaround? We offer multiple rush tiers: Same-day bearing replacement, 24-hour rewinds for smaller motors, weekend work. Call (720) 626-9805 to discuss your timeline.

Motor Repair Pricing

Pricing varies based on motor size, type, and extent of damage. Here are typical ranges:

Standard AC Motor Rewind Pricing:

Motor Size Rewind Only Complete Rebuild
1-5 HP $300-600 $500-900
5-10 HP $500-900 $800-1,400
10-25 HP $800-1,500 $1,200-2,200
25-50 HP $1,200-2,500 $1,800-3,500
50-100 HP $2,000-4,000 $3,000-6,000
100-200 HP $3,500-7,000 $5,000-10,000
200-500 HP $6,000-15,000 $9,000-20,000

Specialty Motor Pricing Multipliers:

  • Explosion-Proof: Add 25-40% to standard pricing
  • High Voltage (>600V): Add 30-50% to standard pricing
  • DC Motors: Add 20-35% to standard pricing
  • Wound Rotor: Add 40-60% to standard pricing
  • Severe Duty: Add 15-25% to standard pricing

Additional Services:

Service Price Range
Bearing Replacement (per bearing) $75-300 + bearing cost
Shaft Machining/Repair $200-800
Dynamic Balancing $150-500
Load Testing $200-600
Vibration Analysis $150-400
Frame Repair/Straightening $300-1,500
Sandblast & Paint $200-800
💰 Free Quote All pricing is approximate. We provide detailed written quotes after inspection. No repair work begins without your approval. Call (720) 626-9805 for accurate pricing on your specific motor.

Our Warranty

What's Covered (1 Year)

  • Rewinding workmanship
  • Insulation system
  • All installed parts
  • Bearing installation
  • Shaft repair work
  • Assembly procedures
  • Testing accuracy
  • Mechanical repairs

What's NOT Covered

  • Misuse or abuse
  • Operating outside nameplate ratings
  • Improper installation after pickup
  • Lightning or power surge damage
  • Contamination after delivery
  • Accidents or external damage
  • Normal bearing wear (unless premature)
✓ We Stand Behind Our Work If your motor fails due to workmanship or materials within the warranty period, we'll repair it at no charge - including parts and labor. We want you to be completely satisfied.

Need Motor Repair or Rewind Service?

Expert repairs, fast turnaround, guaranteed quality. Let's get your motor running again.

3-7 Day Standard Turnaround • Rush Service Available • 1-Year Warranty