Product Core Brief
- Model: EATON MP3010
- Brand: Eaton (Cutler-Hammer)
- Series: MP-3000 / MPrelay motor protection relay
- Core Function: Microprocessor-based motor protection relay that monitors current, detects faults, and controls tripping for industrial motors.
- Product Type: Motor protection relay
- Key Specs: 5 A phase CT input | 120 Vac power supply | 4 Form C outputs | 1× 4-20 mA analog output | RS-232
- Condition: New Original (New Surplus) / Factory Sealed or Tested Surplus, depending on inventory lot
Product Introduction (Rotation Engine)
A failed motor relay rarely announces itself cleanly. It either trips too early, refuses to trip, or loses communication just when you need event history. The Eaton MP3010 addresses that as part of the MP-3000 family, a current-based motor protection relay commonly applied on medium-voltage or larger motors where CT secondary input and programmable outputs are required.
This relay uses Intel-I-Trip overload protection with true-RMS current sampling, allowing it to model motor thermal capacity rather than relying on simple overcurrent thresholds. It provides four programmable Form C outputs, two discrete inputs, and one 4-20 mA analog output for integration into existing control or monitoring loops. For legacy systems still running RS-232 configuration, this unit avoids the need to re-engineer the entire protection scheme.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Product Family | Eaton MP-3000 / MPrelay motor protection relay |
| Model | |
| Power Supply | 120 Vac (MP-3000 base relay family) |
| Phase CT Input | 5 A nominal |
| Ground CT Input | 1 A or 5 A nominal (MP-3000 family) |
| Discrete Inputs | 2 programmable |
| Output Contacts | 4 Form C, programmable |
| Analog Output | 1× 4-20 mA |
| Communication | RS-232 |
| Overload Protection | Intel-I-Trip thermal model with I²t |
| Protection Functions | Overload, jam, phase unbalance, underload, ground fault, instantaneous overcurrent |
| Mounting | Fixed case / panel-mount relay |
Note: Some MP-3000 family features depend on firmware and configuration. Confirm the nameplate and relay settings before installation.
Key Selling Points & Differentiators
- Matches the MP-3000 current-only protection architecture used in many existing motor feeders.
- Four programmable Form C outputs give enough flexibility for trip, alarm, start-permit, and status signaling.
- 4-20 mA analog output supports remote current monitoring without adding separate transducers.
- Intel-I-Trip thermal modeling helps reduce nuisance trips while still protecting motor insulation life.
- RS-232 interface suits legacy configuration laptops and older control rooms.
- Not recommended for new builds that require Ethernet, Modbus TCP, IEC 61850, or advanced arc-flash coordination.
Quality Transparency SOP (DYNAMIC GENERATION)
- Nameplate and Firmware Audit — Verify model MP3010, power supply rating, CT rating, and firmware revision against the physical label.
- Visual and Terminal Inspection — Check CT terminals, output contacts, discrete inputs, RS-232 port, and mounting hardware for corrosion, burnt marks, or loose terminals.
- Power-Up and Self-Test — Apply 120 Vac control power and confirm relay boot, display operation, and absence of internal fault codes.
- CT Injection Test — Use a secondary CT injection kit to verify phase and ground current measurement accuracy and trip timing against configured settings.
- Output and Analog Validation — Verify Form C contact operation and measure the 4-20 mA output with a Fluke multimeter or loop calibrator across several current points.
- ESD-Safe Packing — Place in anti-static packaging with foam support, desiccant, and a recorded test summary.
Technical Risk Avoidance (DYNAMIC GENERATION)
❗ Confirm CT secondary rating before wiring. The MP3010 is specified for 5 A phase CT input in this catalog configuration. Connecting it to a mismatched CT secondary can cause incorrect metering or failure to trip.
❗ Verify the control voltage. This unit is listed for a 120 Vac power supply range in the MP-3010 configuration. Do not assume 24 Vdc or 240 Vac compatibility without nameplate confirmation.
❗ Check RS-232 configuration access. Modern laptops rarely have native serial ports. You may need a reliable USB-to-RS-232 adapter and the correct Eaton configuration software.
❗ Do not reuse old trip settings blindly. If replacing a failed relay, export or photograph the existing settings first. Default settings will not match the motor FLA, CT ratio, or coordination study.
Buyer’s FAQ
1. Is the Eaton MP3010 still in production?
Availability varies by market and inventory lot. Many units are sold as new surplus or tested surplus. Confirm current stock condition before purchase.
2. Is this a genuine Eaton MP-3000 relay?
Yes. MP3010 belongs to the Cutler-Hammer MP-3000 motor protection relay family. Always verify the nameplate, catalog number, and serial number on receipt.
3. Can MP3010 replace other MP-3000 models?
Sometimes, but not automatically. You must match power supply voltage, CT rating, communication interface, and firmware capability. A different suffix may change available inputs or outputs.
4. Does it support Ethernet or Modbus TCP?
No. The MP3010 configuration is documented with RS-232 communication. If Ethernet or Modbus TCP is required, a different MP-3000 or EMR-family relay should be evaluated.
5. What warranty applies to surplus inventory?
Surplus and tested inventory should carry a clear functional warranty and test record. If a seller cannot provide either, treat the unit as unverified.
