Original Siemens Charging Board 6SE7033-5HH84-1HH0 6SE70335HH841HH0 6SE7O33-5HH84-1HHO 6SE7 033-5HH84-1HH0

6SE7033-5HH84-1HH0 | Siemens SIMOVERT MASTERDRIVES PCU2 Precharging Module — Design G and H / 380–575V AC / Chassis Drive Spare

Why MASTERDRIVES Drives Need a Precharging Module

When a SIMOVERT MASTERDRIVES drive is powered up, its DC bus capacitors start with zero charge. Connecting the full mains voltage to an uncharged capacitor bank would draw an instantaneous inrush current far exceeding the rectifier and mains supply rating — potentially damaging the drive, blowing supply fuses, or tripping upstream circuit breakers.

The precharging module solves this by limiting the inrush current during power-up:

Controlled charge-up: The PCU2 precharging module introduces resistance into the rectifier circuit during initial power-up, limiting the DC bus charging current to a controlled, safe level. As the bus capacitors approach full charge voltage, the PCU2 switches out the limiting resistance and connects the full rectifier — completing the power-up sequence cleanly.

Protection timing: The PCU2 module controls the timing of this switching sequence — holding the limiting resistance in circuit until the capacitors are sufficiently charged, then switching to full power. If the charge-up sequence does not complete within the expected time (indicating a fault), the PCU2 generates an alarm.

This precharging process happens every time the drive is powered up — making the PCU2 module one of the most frequently cycled components in the MASTERDRIVES drive system.

Key Specifications

Wide Input Voltage Range — 380 to 575V AC

The 380–575V AC input range of 6SE7033-5HH84-1HH0 covers the full range of standard industrial supply voltages used in the MASTERDRIVES' Design G and H power range:

380–400V AC: Standard European industrial supply voltage. 460–480V AC: North American industrial supply. 500V AC: Nordic and some Eastern European industrial standards. 575V AC: Higher-voltage industrial supplies common in North America for large motor installations.

A single PCU2 module covers this complete voltage range, simplifying spares management across sites with different supply standards.

Application Scenarios

PCU2 module fault — power-up failure: A MASTERDRIVES Design G or H chassis drive fails to complete power-up — a precharging alarm is generated before the DC bus reaches its operating voltage. Diagnostic checks confirm the PCU2 module has failed. Replacement of 6SE7033-5HH84-1HH0 restores correct precharging and normal drive power-up.

Planned maintenance: A facility maintaining large MASTERDRIVES chassis drives proactively replaces the 6SE7033-5HH84-1HH0 precharging module as part of a drive overhaul interval — replacing the most frequently cycled internal component before it fails in service.

FAQ

Q1: What is the difference between PCU1 and PCU2 in the MASTERDRIVES system?

PCU1 (6SE7031-7HF84-1HH1) is the precharging module for MASTERDRIVES Design E and F enclosures — the smaller chassis unit sizes. PCU2 (6SE7033-5HH84-1HH0) is for Design G and H — the larger, higher-power enclosures with bigger DC bus capacitor banks requiring a higher-capacity precharging circuit. The two modules are not interchangeable. Confirm the drive's design letter from its nameplate before ordering.

Q2: What alarms does a failed 6SE7033-5HH84-1HH0 PCU2 produce?

A faulty PCU2 typically produces a precharging fault alarm before the drive enters the "ready" state — the DC bus fails to reach the operating voltage within the expected charge-up time. The fault code and alarm designation varies between MASTERDRIVES software versions but is typically identifiable as a power-up/precharging fault rather than an inverter or motor fault. The drive cannot enable the inverter until the precharging sequence completes successfully.

Q3: Can the precharging module fail due to excessive power cycling?

Precharging modules are designed for frequent power cycling — this is their normal operating condition. However, very high-frequency power cycling (multiple power-on/off cycles per hour over years) increases wear on the module's internal contact switching components. A precharging module that has accumulated an exceptionally high cycle count may develop intermittent or marginal precharging performance before complete failure. Monitoring the precharging time during each power-up can reveal gradual degradation.

Q4: What safety precautions apply when replacing 6SE7033-5HH84-1HH0?

Isolate and lock out the 3-phase mains supply. Wait the full capacitor discharge time specified in the MASTERDRIVES maintenance manual — Design G and H drives carry large capacitor banks that retain hazardous voltage for several minutes after mains isolation. Verify the DC bus voltage is below 50V with a calibrated voltmeter before accessing the module. The PCU2 module itself (0.2 kg) can carry residual charge — discharge any module-internal components before handling.

Q5: Does replacing 6SE7033-5HH84-1HH0 require any drive parameter reconfiguration?

No. Drive parameters are stored in the control unit — not in the precharging module. Replacing the PCU2 does not affect the drive's parameter set. After fitting the replacement module and restoring mains power, verify the precharging sequence completes correctly (DC bus reaches operating voltage within the expected time) before enabling the drive.