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Phone: +86 16626708626Description
Key Technical Specifications
- Rated Capacity: 3.5 kW
- Input Voltage: 200 to 230 VAC, 3-phase (some base -350B variants also support 1-phase — confirm for this exact suffix)
- Input Frequency: 50/60 Hz
- Input Current Rating: 16 A (base -350B family)
- Continuous Output Current: 17 A
- Output Voltage: 170 VAC
- Control Method: Current control and sine-wave PWM; SSCNET serial bus communication
- Cooling Method: Forced ventilation (fan)
- Enclosure Rating: IP00 (open enclosure — panel/cabinet mount only)
- Operating Temperature: 0°C to 55°C; Storage: -20°C to 65°C
- Braking: Built-in dynamic brake (base family)
❗ Note: The “-EG171” suffix denotes a customer-specific or special-application firmware/parameter variant of the standard MR-J2S-350B — this pattern is confirmed across other MR-J2S-B capacities (e.g., -60B-EG171, -200B-EG171) but Mitsubishi does not publish a general datasheet covering what EG171 changes functionally versus the base amplifier. Confirm against your machine builder’s documentation or the unit’s own parameter sheet before treating this as a drop-in swap for a plain MR-J2S-350B — special-suffix units can carry different default parameters, I/O assignments, or motor-matching settings.
Product Introduction
The Mitsubishi MR-J2S-350B-EG171 is an AC servo amplifier in the MELSERVO MR-J2S line, rated at 3.5 kW and built to run on a 200–230 VAC 3-phase supply. It uses SSCNET serial bus communication and current/sine-wave PWM control, delivering 17 A continuous output to drive a matched servo motor in motion control applications.
The “-EG171” designation marks this as a special-application variant rather than the plain catalog -350B. That distinction matters at replacement time — machine builders often spec these custom suffixes with parameters tuned to a specific motor or application, so matching the exact suffix (not just the base model) is the difference between a clean swap and a unit that needs reprogramming.
MR-J2S-350B-EG171
MR-J2S-350B-EG171
Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| No display / dead amplifier | Loss of input power, blown fuse, or amplifier failure | ✅ High | Measure 200-230 VAC at the input terminals with a multimeter | Confirm input power is present before assuming the amplifier failed |
| Alarm code on display, motor won’t run | Amplifier-detected fault (varies by alarm number) | ✅ High | Read the alarm/warning code and cross-reference the MR-J2S instruction manual | Alarm codes point to a specific fault category — don’t swap the amplifier blind; diagnose the code first |
| Motor runs rough or hunts at low speed | Servo tuning/gain parameters, not necessarily amplifier failure | ❌ Low | Check autotuning/gain parameters against the machine builder’s setup sheet | Often a parameter/tuning issue — verify settings before replacing hardware |
| SSCNET communication error | Fiber-optic cable fault, connector issue, or amplifier comm failure | ✅ High | Inspect SSCNET fiber cable for damage/dirty connectors, check for consistent errors across multiple amplifiers on the chain | If one amplifier in the chain consistently faults and others don’t, that unit is the likely cause |
| Dynamic brake doesn’t hold on e-stop | Brake circuit wiring or amplifier brake output failure | ✅ High | Check brake circuit continuity and voltage at the amplifier’s brake output terminals | ❗ Treat this as safety-critical — don’t return the machine to service until brake holding is confirmed |
If you’re still stuck, contact technical support with the amplifier’s full nameplate (including the suffix), the exact alarm code displayed, and your machine builder’s parameter sheet if available — special-suffix units are hard to troubleshoot generically without that context.
Frequently Asked Questions (FAQ)
Can I replace this with a standard MR-J2S-350B (no suffix)?
Not without checking first. The suffix typically indicates custom parameters or firmware tied to a specific machine application. A base -350B may power up fine but run with the wrong default settings for your machine. Get your machine builder’s setup documentation before assuming a plain -350B is interchangeable.
Is the MR-J2S series still supported by Mitsubishi?
MR-J2S is a legacy MELSERVO generation — Mitsubishi’s current lines are MR-J4 and MR-J5. Parts availability for MR-J2S now runs through new-old-stock and surplus channels rather than active factory production.
Does this support SSCNET III (fiber) or the original SSCNET (electrical)?
MR-J2S-series amplifiers use the original SSCNET, not SSCNET III/H (which came with the MR-J3/J4 generations). Don’t mix generations on the same network without confirming compatibility — they’re not interchangeable communication protocols.
Will programming/parameters transfer if I swap in a new unit?
No — parameters live on the amplifier itself (or are set via the controller, depending on your architecture). If you’re swapping to a new unit, back up your parameter settings from the outgoing amplifier first if at all possible, and be ready to re-enter them.
Is this new or refurbished?
Field listings for this part show up as new/new-old-stock. Confirm the specific condition and whether original packaging/documentation is included with your seller before ordering.
What’s the warranty on a legacy servo amplifier like this?
That’s seller-dependent — since Mitsubishi’s factory warranty doesn’t extend to aftermarket/surplus channels on a discontinued generation, ask the specific seller what coverage (if any) comes with the unit.
