WhatsApp: +86 16626708626
Email: 
Phone: +86 16626708626Description
Key Technical Specifications
- Rated Power: 0.5 kW
- Rated Speed: 4,000 min⁻¹ (RPM)
- Rated Torque: 1.2 Nm
- Standstill Torque: 1.5 Nm
- Rated Current: 1.5 A
- Standstill Current: 1.6 A
- Torque Constant: 0.96 Nm/A
- Voltage Constant: 58 mV·min
- Rated Supply Voltage: 400/460 V AC
- Protection Rating: IP 64
- Weight: 2.9 kg
- Ambient Temperature Range: 5 to 40 °C (derates above 40 °C)
- Climate Category: 3K3 per EN 50178
Product Introduction
The Kollmorgen 6SM 37L-4.000 is a permanent-magnet synchronous servo motor from the legacy 6SM line, rated for 0.5 kW at 4,000 RPM with 1.2 Nm continuous torque. It’s built for closed-loop positioning duty on transfer lines, machine tools, and older robotic cells running Kollmorgen or Danaher Motion drive systems.
Buyers keep sourcing this specific frame size because the flange dimensions, shaft, and feedback interface line up with existing rack wiring — swap the motor without touching the drive configuration or mechanical mounts. IP 64 sealing holds up in shop-floor dust and coolant spray, which is why it’s still pulled for retrofit jobs instead of a full axis redesign.
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| Motor doesn’t turn, no fault on drive | Broken feedback cable or connector | ✅ High | Check resolver/encoder cable continuity, inspect connector pins | Replace or reseat cable before condemning motor |
| Drive throws “Following Error” or overcurrent trip | Winding short or open phase | ✅ High | Megger test each phase-to-phase and phase-to-ground, compare to 500 V / >10 MΩ baseline | Winding fault is usually terminal — replace motor |
| Excessive vibration or grinding noise | Bearing wear | ✅ High | Rotate shaft by hand, listen/feel for roughness with power off | Bearing failure confirms hardware replacement |
| Motor runs hot, thermal switch trips | Overload from mechanical bind or undersized duty cycle | ❌ Low | Check load torque against 1.2 Nm rated / 1.5 Nm standstill limits | Investigate mechanical load path first, motor is often fine |
| No motion, drive shows healthy status | Bad drive output stage or blown fuse on power stage | ❌ Low | Measure output voltage at motor terminals with drive commanded to run | Troubleshoot drive/PSU before replacing motor |
| Intermittent cutout under load | Loose terminal block wiring, vibration-induced connection fault | ❌ Low | Retorque terminal screws, inspect for chafed insulation | Usually a wiring issue, not the motor itself |
If you’re still stuck after these checks, send us the diagnostic buffer readout and a photo of the terminal wiring — we can usually tell you in one email whether it’s the motor or something upstream.
6SM 37L-4.000
6SM 37L-4.000
Frequently Asked Questions (FAQ)
Is this motor still made by Kollmorgen?
No. The 6SM 37L-4.000 has been discontinued by the manufacturer for years — it’s a legacy frame from the Kollmorgen-Seidel era. We’re not going to pretend otherwise. What we stock is pulled inventory and tested surplus units, not factory-new production.
Can I get a direct drop-in replacement, or do I need to modify anything?
If your existing wiring, feedback cable, and mounting flange match the original 6SM 37L-4.000 footprint, this swaps in without rewiring. Where it gets messy is the feedback connector pinout — some 6SM variants (the -09, -G, -J suffixes) use different resolver wiring or supply voltage. Confirm your exact suffix against the nameplate on the unit you’re pulling before you order.
Does this need to be programmed or configured after installation?
The motor itself holds no firmware or configuration — all the motion parameters (current loop gains, feedback scaling) live in the drive, not the motor. Swapping the motor won’t touch your drive’s program. Just verify the feedback type matches what the drive expects.
Why is this cheaper than buying new from Kollmorgen?
Because it isn’t new from Kollmorgen — it can’t be, the part’s obsolete. What you’re paying for is a pulled unit that’s been through insulation resistance testing, load run, and visual inspection. That’s a different cost basis than a factory production run, and we price it that way.
What’s your testing process before you ship one of these?
Inbound units get a visual inspection for corrosion, shaft damage, and rework marks, then insulation resistance testing at 500 V (we look for >10 MΩ phase-to-ground). We run it under load on a test rig and log winding temperature. You get a test report with the unit — ask and we’ll send photos or video from that specific serial number before you commit.
Is it hot-swappable — can I pull it with the system live?
No. Kill power to the drive and the servo loop before disconnecting anything. Pulling a live motor connector can arc across the feedback pins and take out the drive’s input stage with it, which turns a 600 motor swap into a 3,000 drive repair. Not worth the ten minutes you’d save.
What if I’m not sure this is the right motor for my system?
Send us the nameplate photo off your existing motor — full suffix, not just “6SM 37L-4.000.” The base part number covers several electrically different variants (voltage, feedback type, brake option), and matching the suffix is the difference between a clean swap and a fried drive on power-up.
