Home
>
Products
>
CNC Circuit Board
>
|
| Place of Origin | Germany |
| Brand Name | SIEMENS |
| Certification | CE ROHS |
| Model Number | 6SE7033-7EH84-1GG0 |
Part Number: 6SE7033-7EH84-1GG0
Manufacturer: Siemens AG (Germany)
Product Type: Inverter Wiring Board — SML2 (Inverter Snubber/Signal Wiring Board)
Product Range: SIMOVERT MASTERDRIVES 6SE70
Compatible Drive: 6SE7033-7EH series chassis drives
Production Status: Discontinued by Manufacturer
Country of Origin: Germany
The 6SE7033-7EH84-1GG0 is the SML2 inverter wiring board for the Siemens SIMOVERT MASTERDRIVES 6SE7033-7EH series chassis drives — the companion board to the SMU2 wiring board within the same drive's power section assembly.
The SML2 (Snubber Module Lower / Signal Module Lower — the naming reflects its position and function within the drive's internal hierarchy) handles the snubber circuit interface and power section signal wiring for the lower portion of the inverter bridge in this large-chassis MASTERDRIVES variant.
Discontinued by the manufacturer, the 6SE7033-7EH84-1GG0 is a spare part sourced exclusively through the aftermarket for repair and maintenance of operational 6SE7033-7EH drives still in service.
At the power ratings of the 6SE7033-7EH chassis, these drives are typically installed in applications where they run continuously for extended periods — industrial processes, utilities, and large production facilities where replacement and recommissioning represents significant effort and cost.
Reliable spare board availability is therefore a direct factor in machine availability for these installations.
The GG0 suffix distinguishes this SML2 board from the SMU2 board (suffix GF0). Both boards are installed in the same drive chassis and are functionally paired — they share the same power section environment and are physically located in proximity within the drive's internal assembly.
Together, these two boards form the complete inverter wiring and signal interface assembly for the 6SE7033-7EH power section.
| Parameter | Value |
|---|---|
| Part Number | 6SE7033-7EH84-1GG0 |
| Manufacturer | Siemens AG |
| Product Type | Inverter Wiring Board — SML2 |
| Product Range | SIMOVERT MASTERDRIVES 6SE70 |
| Compatible Drive | 6SE7033-7EH series |
| Production Status | Discontinued by Manufacturer |
| Country of Origin | Germany |
In large-format IGBT inverters, the IGBT switching transitions generate voltage transients on the DC bus and the motor output.
These transients — if unclamped — exceed the IGBT's safe operating voltage and cause device failure.
Snubber circuits are the passive damping networks that absorb and dissipate this transient energy, preventing overvoltage damage to the power semiconductors.
The SML2 board serves as the snubber circuit assembly and interconnect board within the 6SE7033-7EH inverter. In this role, it carries the snubber components — resistors, capacitors, and potentially diodes — that are electrically connected across the IGBT terminals and the DC bus to damp switching transients.
It also provides the PCB routing for the signal and gate drive connections within its section of the power bridge.
At the current ratings of the 6SE7033-7EH chassis, the energy in each switching transient is substantial.
Proper snubber dimensioning and low-inductance circuit layout are not optional — they are essential to keeping transient voltages within the IGBT module's safe limits during normal operation.
The SML2 board's design accounts for this requirement through the specific component values and layout geometries used in the 6SE7033-7EH power section.
The 6SE7033-7EH drive uses both the SML2 (6SE7033-7EH84-1GG0) and the SMU2 (6SE7033-7EH84-1GF0) boards in its power section assembly.
These two boards are not alternatives — they are both installed simultaneously and serve complementary functions.
The SMU2 primarily handles the upper-level signal routing: gate drive distribution and measurement signal collection from the control to and from the power bridge. The SML2 handles the snubber function and the lower-level signal connections within the power bridge itself.
Together, they complete the signal and protection circuit path between the control electronics and the IGBT modules.
This two-board architecture is characteristic of the larger MASTERDRIVES chassis designs.
Smaller drives often use a single combined board for these functions; the larger power sections require the split layout to accommodate the physical space and circuit complexity at higher current ratings.
The 6SE7033-7EH84-1GG0 was discontinued by Siemens. This is expected for a product family of the MASTERDRIVES generation, which has been superseded by the SINAMICS platform. However, the installed population of 6SE7033-7EH drives running in productive service globally remains significant — these drives serve in applications where their replacement would require not just new drive hardware but also engineering evaluation, system re-parameterisation, and potentially mechanical interface changes.
Spare SML2 boards are available from the specialist MASTERDRIVES aftermarket, typically as exchange units that have been tested and verified for normal operation.
When sourcing, verify the board revision (GG0) against the revision label on the installed board, as minor variants within the SML2 designation may exist across different production periods.
Q1: After a DC bus overvoltage event, the drive shows repeated F034 IGBT faults. The IGBT modules have been tested and measured intact. Could the 6SE7033-7EH84-1GG0 SML2 board be damaged?
Overvoltage events can damage snubber components on the SML2 board — specifically the snubber capacitors, which absorb the energy of voltage transients.
A damaged snubber capacitor (short-circuit or open-circuit) changes the clamping behaviour of the snubber network.
An open-circuit snubber capacitor removes the transient clamping entirely, allowing higher transient voltages on IGBT collector-emitter junctions that the IGBT protection circuit interprets as a fault. Inspect the SML2 board's snubber components for physical damage before concluding the fault is in the IGBT module.
Q2: The 6SE7033-7EH84-1GG0 and 6SE7033-7EH84-1GF0 appear visually similar. Is there a risk of installing the wrong board in the wrong position?
The two boards have different connectors and mounting positions within the drive's power section assembly.
They are designed to prevent accidental interchange — the connector keying and physical mounting points differ between SMU2 and SML2.
That said, never rely solely on visual similarity when handling spare parts for MASTERDRIVES chassis drives.
Always confirm the part number printed on the board's label against the required part number before installation.
Q3: The SML2 board shows a visibly burned component near one of the snubber resistors. Can the board be repaired, or is replacement the only option?
Component-level repair of the SML2 board is possible in principle — the snubber resistors and capacitors are standard-value passive components accessible to electronics repair technicians.
Whether repair is practical depends on: the availability of exact replacement component values, the condition of the PCB traces and pads surrounding the burned component, and whether secondary damage extends beyond the visible component.
For a one-off repair in a production environment, board replacement is typically faster and more reliable than component-level repair unless a specialised drive repair service is used.
Q4: The machine uses a water-cooled 6SE7033-7EH series drive. Does this affect which SML2 board variant is required?
Air-cooled and water-cooled variants of the 6SE7033-7EH series can use the same SML2 board part number, as the snubber and signal wiring function is not directly dependent on the cooling method.
The cooling method affects the heatsink and IGBT mounting assembly, but the SML2 board's circuit function and connections remain the same.
Verify against the specific drive's hardware documentation to confirm no variant exists for water-cooled configurations.
Q5: How should the 6SE7033-7EH84-1GG0 be stored to maintain its condition as a long-term spare?
The SML2 board contains passive components — resistors and capacitors — that are not as sensitive to storage conditions as semiconductor-based boards.
However, long-term storage still requires: ESD-protective packaging to prevent damage to any semiconductor elements on the board, protection from moisture (use sealed bags with desiccant if storing in variable-humidity environments), and a stable temperature environment avoiding extended high-temperature exposure that can degrade capacitor electrolyte. Record the date of storage.
If the board is retrieved from storage after more than five years, a bench inspection of the snubber capacitors for ESR drift is advisable before installation.
Contact Us at Any Time
