Description
The Emerson SPMC2402 (also branded Control Techniques) is a controlled input rectifier module in the Unidrive SPM series. It uses a dual half-controlled thyristor bridge to convert three-phase AC mains into a regulated DC link voltage, serving as the front end for SPMD inverter modules or as a standalone DC supply for multiple smaller drives.
As a member of the SPMC family—”C” denoting Controlled—the SPMC2402 differs from its uncontrolled SPMU cousins by offering phase-angle-controlled turn-on. This enables smooth, inrush-free DC bus pre-charging, adjustable DC link voltage, and the ability to draw 6-, 12-, or 18-pulse supply currents when multiple bridges are paralleled for harmonic mitigation.
Application Scenarios
Picture a steel rolling mill where a single 400 V bus feeds six SPMD inverter modules driving roughing and finishing stands. The motors regenerate massively during deceleration, and the incoming supply is already strained by arc furnaces and harmonics. A standard diode rectifier would hammer the bus on every start and contribute another pulse of distortion. Instead, the plant installs three SPMC2402 modules in a 6-pulse/12-pulse configuration, each with its own line reactor and interphase transformer. The thyristors fire progressively, ramping the DC bus up smoothly through the built-in soft-start sequence. No contactor chatters, no upstream breaker trips on inrush, and the measured harmonic content stays within utility limits.
Now consider a mining conveyor with a 130 kW motor hundreds of meters from the drive cabinet. The long motor cable makes voltage notching a real concern. The maintenance team chooses the SPMC2402 not just for its current rating but because its controlled topology tolerates supply notching better than an uncontrolled diode bridge. The result: clean starts, stable DC link, and one less reason for an unplanned conveyor stoppage.
These scenarios show why the SPMC2402 earns its place in demanding applications. It is not merely a rectifier—it is the controllable gateway between the utility and every inverter downstream.
Parameter
| Main Parameters | Value/Description |
|---|---|
| Product Model | SPMC2402 |
| Manufacturer | Emerson / Control Techniques |
| Product Category | Controlled Input Rectifier Module (half-controlled thyristor bridge) |
| Product Series | Unidrive SPM |
| Rectifier Topology | Dual half-controlled thyristor (SCR) bridge |
| Input Voltage | 380–480 V AC, 3-phase, ±10%, 50/60 Hz |
| Input Voltage Rating Class | 400 V class (model digit “4”) |
| Number of Rectifier Stages | 2 (dual stage; model digit “2”) |
| DC Output Voltage | 513–648 V DC (proportional to input) |
| Continuous Output Current | 2 × 345 A DC (approx. 552 A total) |
| Peak DC Link Current | 758 A (100% normal-duty rating) |
| AC Line Current (typical) | 2 × 308 A |
| AC Line Current (maximum) | 2 × 312 A |
| Control / Auxiliary Supply | External 24 V DC / 3 A (must be present for operation) |
| Soft-Start | Built-in (standard on all SPMC modules) |
| Fusing – Semiconductor | 450 A, IEC class aR |
| Fusing – HRC / Back-up | 400 A, IEC class gG / UL class J |
| 24 V Supply Protection | 4 A slow-blow fuse per supply pole |
| Maximum DC Bus Capacitance | 132 mF (supply fault level <25 kA); 66 mF with INL412 reactor |
| AC Input Cable Size | 2 × 120 mm² (2 × 4/0 AWG) |
| DC Output Cable Size | 2 × 120 mm² (2 × 4/0 AWG) |
| Control Wiring | 0.5 mm² |
| Status Relay Contacts | 250 V AC / 6 A non-inductive; 40 V limited: 4 A DC; 250 V limited: 400 mA DC |
| Cooling Method | Forced-air cooling (fan required) |
| Maximum Power Loss | Approx. 1,737 W |
| Power Range of SPM Platform | 45 kW – 1.9 MW (system dependent) |
| Mounting | Cabinet-mounted; live parts require protective covers |
| Approximate Dimensions | 399 × 298 × 310 mm |
| Approximate Weight | 20 kg |
| Protection Class | IP20 (cabinet installation) |
| Operating Temperature | -40 °C to +70 °C (confirm against original nameplate) |
