Original Siemens Cib Comm. Component 6SL3351-6GH32-2AB3 6SL33516GH322AB3 6SL3 351-6GH32-2AB3

Siemens 6SL3351-6GH32-2AB3 | SINAMICS G Replacement Control Interface Board — 660–690V, 215A, 50/60Hz

Part Number: 6SL3351-6GH32-2AB3

Manufacturer: Siemens AG (Germany)

Product Category: Other Converters — Spare Part PCB

Product Family: SINAMICS 

Overview

The 6SL3351-6GH32-2AB3 is a Siemens SINAMICS G replacement control interface board — the control layer spare part for a SINAMICS G Power Module operating on 660–690V three-phase AC at a rated output current of 215A.

This board sits between the drive's power section IGBTs and its control electronics. It generates the gate drive pulses that switch the IGBT transistors, reads the phase current feedback from the power module's sensing circuits, monitors heatsink temperature, and implements the local protective logic that shuts the drive down if safe limits are exceeded.

The 215A current rating at 690V corresponds to motors in the 200kW range — a substantial load in pump, fan, compressor, and general industrial drive applications.

SINAMICS G drives at this power level are found in water infrastructure, industrial HVAC, process cooling, air separation plants, and large-scale industrial ventilation installations. 

hese are often critical-duty machines where unplanned downtime has a significant operational and financial cost, making reliable spare parts like the 6SL3351-6GH32-2AB3 important to keep available.

The AB3 revision is the fourth and latest production version of this board, following AB0, AB1, and AB2. Each revision incorporated component updates.

AB3 represents the current Siemens specification for this power module variant and is the recommended replacement regardless of which earlier revision was originally installed.

Key Specifications

660–690V Networks and the 215A Operating Range

The 660–690V supply standard is used in industrial facilities where higher voltage distribution reduces cable cross-section requirements and line losses. At 690V, a 215A output current delivers just over 200kW to the motor — a common size in large industrial pumps and fans.

Running on 690V rather than 400V means this power is achieved at lower current, which reduces conductor costs and motor winding losses for the same shaft power.

The 6SL3351-6GH32-2AB3 board operates in the elevated voltage environment that comes with 690V supply — the DC bus in this power module charges to approximately 975V after rectification.

Every part of the gate drive circuitry on this board is designed to function reliably at this DC bus level.

Gate drive isolation, voltage rating of gate drive components, and over-voltage clamping on the IGBT gate terminals are all specified for the 690V drive environment.

Control Interface Board — What It Does in the Drive

Within the SINAMICS G Power Module, the control interface board serves as the electronics layer that makes the power conversion happen.

The upstream Control Unit sends PWM duty cycle commands — calculated by the current control algorithm — to the 6SL3351-6GH32-2AB3. The board translates these commands into precisely timed gate pulses for the six IGBTs that make up the three-phase inverter bridge in the power module.

Simultaneously, the board samples the motor phase currents at each switching cycle, using the power module's current sensors.

These readings are the input to the closed-loop current control. Any deviation between the commanded and measured current triggers an immediate correction in the next PWM cycle — a process that happens thousands of times per second.

Temperature monitoring runs in parallel. NTC thermistors on the heatsink send temperature readings through this board. When the heatsink temperature rises toward its operational limit, the CU applies a derating.

At the shutdown threshold, the board implements the hardware-level trip, cutting gate pulses to all IGBTs regardless of any software command.

Revision AB3 — Field Replacement Notes

The 6SL3351-6GH32-2AB3 is a direct drop-in replacement for any earlier AB-revision board in the same 215A, 660–690V SINAMICS G power module. No parameter changes are needed after installation. The drive's commissioning data is stored in the Control Unit, not in the power module board. After fitting the new board and reconnecting all power module internal connectors, the drive can be returned to service after a standard startup check.

One practical note: always confirm connector seating during installation.

The board connects to the power module via several internal connectors carrying gate drive signals, current sensor feedback, and NTC temperature data.

A partially seated connector produces the same symptom as a failed board — the drive trips at startup with a hardware fault. 

Visually and tactilely verify each connector before closing the drive cabinet.

Handling and High-Voltage Safety

The 6SL3351-6GH32-2AB3 is installed inside a 690V drive cabinet. Before any internal access, the mains supply must be fully isolated, and the DC bus must be allowed to discharge — minimum five minutes after isolation, confirmed by measuring below 50V at the DC bus terminals.

At 690V supply, the DC bus charges to nearly 1000V, which remains lethal for several minutes after isolation.

Handle the board with ESD precautions. The gate drive ICs and current sensing components are sensitive to electrostatic discharge.

Use a wrist strap and conductive work surface. Store and transport in conductive anti-static packaging.

FAQ

Q1: After replacing the 6SL3351-6GH32-2AB3, the drive shows an F30017 (heatsink overtemperature) alarm at startup, even though the heatsink is cold. What is the cause?

F30017 at a cold startup after board replacement almost always means the NTC temperature sensor connector on the board has not been fully seated.

The drive reads an open-circuit NTC as maximum temperature and trips on overtemperature. 

Power down, discharge the DC bus, recheck and firmly reseat the NTC connector, then restart. If the fault persists after confirmed connector seating, the NTC sensor itself may be damaged.

Q2: Is the 6SL3351-6GH32-2AB3 compatible with SINAMICS G drives with PROFIBUS or PROFINET Control Units?

Yes. The control interface board in the Power Module is independent of the communication interface on the Control Unit. The CIB handles the power module's internal functions — gate drive, current sensing, temperature monitoring.

The communication protocol (PROFIBUS, PROFINET, or USS) is handled entirely by the Control Unit, which is a separate unit from the Power Module and its board.

The 6SL3351-6GH32-2AB3 board replacement does not affect or require changes to the CU or its communication configuration.

Q3: The drive runs but shows intermittent F30001 (overcurrent) alarms at partial load with no motor changes. Is the 6SL3351-6GH32-2AB3 involved?

Intermittent overcurrent at partial load with a confirmed-healthy motor points to a drifted current sensor on the board.

The sensor's zero-current offset has shifted, causing the measured current to occasionally exceed the trip threshold even when actual motor current is well within limits. 

This drift typically worsens as the board ages and as internal temperatures cycle. Board replacement with the 6SL3351-6GH32-2AB3 is the correct repair.

Q4: Can the AB3 revision board be installed in a drive that originally used AB0, without any compatibility issues?

Yes, full backward compatibility across AB0, AB1, AB2, and AB3 revisions is maintained by Siemens for this board.

The AB3 is the recommended spare for all installations regardless of original revision. 

No additional configuration, parameter change, or software update is required when moving from any earlier AB revision to AB3.

Q5: The 215A SINAMICS G drive at 690V is running a large pump. What symptoms should maintenance staff watch for that would indicate a failing control interface board before it causes an unplanned shutdown?

Early warning signs of a deteriorating control interface board include: intermittent overcurrent trips that clear on reset and reoccur under similar load conditions; slight but progressive increase in motor current imbalance between phases at steady load; drive trips on heatsink overtemperature even though the cooling fan is operating and the heatsink is not physically hot; and fault codes that are inconsistent with the operating conditions and do not repeat in a pattern that points to a specific load event.

Any of these trends warrant board inspection and likely replacement before failure causes unplanned production loss.