Siemens Master Drives 6SE70 Spare Parts Identification Guide

Siemens Master Drives 6SE70 Spare Parts Identification Guide

Overview of the SIMOVERT MASTERDRIVES 6SE70 Family

The Siemens SIMOVERT MASTERDRIVES series (order family 6SE70) is the third-generation vector-controlled drive platform covering both the voltage-source VC (Variable-speed Control) and current-source MC variants. The platform spans compact frame sizes 1 through 3 and chassis frame sizes 4 through 7, plus the active line-side rectifier module (Active Line Interface, ALI), collectively covering approximately 0.55 kW to 6000 kW with paralleled inverter stages. Each drive is identified by a unique MLFB (MaschinenLesbare FabrikateBezeichnung, i.e., machine-readable product designation) that encodes power class, voltage rating, control variant, options, and hardware revision. Without opening the enclosure, the MLFB plus the option-code annex can be used to derive the complete internal board complement (IGD, PSU1, IVI, CU, and option boards) by cross-referencing the Siemens Industry Online Support (SIOS) spare-parts portal and the legacy Spares on Web database.

The challenge with multi-drive fleets is straightforward: maintenance engineers must stock spares that map cleanly to the installed base, yet Siemens may return a "replace complete unit" recommendation rather than a board-level Bill of Materials (BOM). This reference provides a deterministic workflow for extracting the internal board complement from the MLFB and populating a spare-parts database without dismantling any drive.

MLFB (Order Number) Structure for 6SE70 Drives

The Siemens MLFB is a hierarchical 16-character alphanumeric code. For the 6SE70 family, the structure is:

6 S E 7 0 XX - Y Y Y Y Y - Z A A 0
│ │ │ │ │ │  │   │ │ │ │ │ │  │ │ └─ Hardware revision placeholder
│ │ │ │ │ │  │   │ │ │ │ │ │  └─┴── MLFB placeholder
│ │ │ │ │ │  │   │ │ │ │ └─────── Software variant
│ │ │ │ │ │  │   │ │ │ └───────── Option codes (Z-annex)
│ │ │ │ │ │  │   │ │ └─────────── Hardware variant
│ │ │ │ │ │  │   │ └──────────── Voltage / cooling variant
│ │ │ │ │ │  │   └────────────── Frame size / power class
│ │ │ │ │ │  └────────────────── Family separator
└─┴─┴─┴─┴─┴─ Product family (MASTERDRIVES, 6SE70)

For the specific MLFBs cited in the source fleet, the role, frame, and approximate power class can be read directly:

Frame Size, Power Rating, and Internal Board Complement

The 6SE70 platform uses a single logical hardware architecture: every drive contains the same functional set of internal boards, scaled by frame size to accommodate higher IGBT gate-charge currents and DC/DC supply currents. The mapping from MLFB frame to internal board complement is:

Internal Board Reference by Function

The internal electronics of a 6SE70 drive consist of the following sub-assemblies. Each can be identified from the MLFB plus option codes, eliminating the need to open the unit.

IGD — IGBT Gate Driver Board

The IGD generates the isolated gate-drive signals and provides desaturation (V_CE,sat) short-circuit protection for each IGBT module. IGD boards are frame-specific because their isolated DC/DC converter must supply sufficient gate charge to the larger IGBT modules used in higher-power frames.

• Frames 1–3: Single-board IGD, mounted directly on the IGBT stack; single fiber-optic link to the CU.
• Frames 4–5: Separate IGD per phase leg, fiber-optic links between the CU and each phase.
• Frames 6–7: IGD is integrated into a "Smart IGBT" power module with on-board gate driver and fiber-optic interface.

PSU1 — Power Supply Unit 1

PSU1 converts the DC-link voltage (or auxiliary 24 V where present) into the isolated +5 V, +15 V, and –15 V rails required by the control electronics. A failed PSU1 typically presents as a dead drive with no LED activity on the CU. The PSU1 output voltages can be measured at test points on the CU without dismantling the drive:

IVI — Inverter Voltage/Current Interface

The IVI (sometimes referenced as CUSA in chassis frames) is the analog front end that conditions the DC-link voltage, motor phase current (via LEM modules), and motor temperature (via PTC or KTY84) signals before they are digitized on the CU. Compact frames (1–3) integrate IVI onto the CU or onto a small daughterboard; chassis frames (4–7) use a separate IVI/CUSA board with optical isolation to the power section.

CU — Control Unit (CU1 / CU2 / CU3)

The CU contains the DSP, firmware EEPROM, parameter memory, and operator panel interface. Three hardware variants exist:

• CU1: 16-bit, single-axis, basic I/O. Used in cost-sensitive compact frames.
• CU2: 32-bit, dual-axis (suitable for 6SE70 active-front-end + inverter pairs), extended I/O.
• CU3: 32-bit, multi-axis (used in MC current-source drives and chassis VC drives for paralleled inverter stages).

The CU variant is fixed by the drive's MLFB and is not user-configurable in the field.

Option Boards

Optional communication and I/O boards plug into the CU's option slots. The presence of each is encoded in the MLFB option code (e.g., +G91 for PROFIBUS, +L30 for SIMOLINK):

Spare-Parts Identification Workflow (Without Dismantling)

The following procedure identifies the internal board complement of any 6SE70 drive using only the MLFB and the option codes printed on the drive's nameplate.

1. Record the MLFB exactly as printed. Photograph the nameplate at a resolution sufficient to read the small print. The MLFB is typically on the left side of the drive's front panel or on the inside of the terminal cover.
2. Capture all option codes (the Z field). Each option code (e.g., +G91+L30+K01) identifies one optional board that must be present in the BOM.
3. Open the Siemens Industry Online Support portal at support.industry.siemens.com. Enter the MLFB. The portal returns the "Spares List" — a tree of spare-part numbers grouped by sub-assembly (electronics, power section, mechanical).
4. Cross-reference the Spares List to the frame-power map in the table above. Verify that the listed IGD, PSU1, and IVI part numbers match the expected frame for the drive's power rating.
5. Use the COMBO configurator if the SIOS portal does not return a board-level breakdown. COMBO is the legacy Siemens drive-configurator used by sales engineers and contains the original BOM for each MLFB.
6. Generate a fleet spare-parts matrix by entering each drive's MLFB into a spreadsheet and pivoting on the IGD, PSU1, IVI, and CU part numbers. Drives sharing the same frame size will share most spares — typically reducing a 13-drive fleet to 4–6 unique spare-part numbers per sub-assembly.

Siemens Spares-on-Web Access and Migration to SIOS

The original Spares-on-Web portal was progressively migrated into the Siemens Industry Online Support (SIOS) ecosystem. Engineers looking up 6SE70 spares today should use the SIOS entry page for the specific MLFB:

1. Navigate to SIOS.
2. Enter the full MLFB (e.g., 6SE7024-7TD61-Z) into the product search bar.
3. Open the product page. Select Spare Parts from the right-hand navigation.
4. The portal returns a download link for an Excel spreadsheet listing each spare part number with its description, suitable for direct import into an EAM/CMMS.

For a fleet of 13 drives as cited in the source, the typical time investment is:

• First drive: 45 minutes (portal familiarization, MLFB validation, BOM verification)
• Subsequent drives: 5–10 minutes each
• Total fleet BOM build: approximately 2.5 hours

Spare-Parts Strategy for Multi-Drive Fleets

For the 13-drive fleet cited in the source, the following stocking recommendation minimizes mean-time-to-repair (MTTR) while avoiding overstock:

Verification Procedures

Once a spare-parts list has been built from the MLFB, the following steps verify that the spares will fit and function in the actual drives before a fault event.

1. Visual verification: Confirm that the spare board's part number matches the installed board's part number exactly, including the suffix that denotes hardware revision.
2. Mechanical verification: Insert the spare board into each drive it is intended to serve. Verify that all connectors mate correctly and that the board seats without forcing.
3. Electrical verification: With the drive powered and the motor disconnected, swap the spare board into the drive and verify:
   • PMU display shows "READY TO RUN" or equivalent state.
   • DC-link voltage reading matches the input line voltage × √2 within ±5 %.
   • No fault code (e.g., F001, F004, F005, F008) appears within 60 seconds of power-up.
4. Firmware verification: Use DriveMonitor (legacy tool) or STARTER (current) over the serial USS interface to verify that the firmware version on the spare board matches the production drives, or is at minimum compatible. Use parameter r060 to read the control-board identifier.
5. Parameter cloning: Use the CU's parameter-set upload/download function (parameter P060 = 1 to upload, 2 to download) to clone the production parameter set to the spare board.

Common Fault Codes and Board-Level Root Causes

The following fault codes are most often resolved by board-level replacement rather than complete drive replacement:

Migration Considerations to SINAMICS

Given the long-term spare-parts risk, maintenance engineers should plan migration from 6SE70 to SINAMICS S120 or SINAMICS G150/G180. Key migration considerations:

• Power terminals: SINAMICS uses the same input/output terminal pattern as 6SE70 for most power classes, allowing direct swap with minor wiring changes.
• Control terminals: The X122/X132 control-terminal pin-out differs between platforms; rebuild the control-wiring harness.
• Parameter mapping: Siemens provides a parameter cross-reference (the "Migration Kit") that maps 6SE70 parameters to SINAMICS parameters. Common mappings include:
  • P060 (parameter set) → p0971 (parameter save)
  • P100 (control-word source) → p1500 (setpoint source)
  • Parameter sets 1–4 → DDS0–DDS3
• Firmware cloning: STARTER or Startdrive cannot directly import 6SE70 parameter files. Use DriveMonitor to export to ASCII, then write a STARTER script to translate the parameter values.
• Encoder compatibility: SINAMICS supports HTL/TTL encoders via the SMC10/SMC20 modules; existing 6SE70 encoders are generally reusable.

Field-Commissioning Checklist for Spare-Board Swaps

1. Lock out and tag the drive's input circuit breaker. Wait 5 minutes for DC-link discharge. Verify 0 V DC at the DC-link test points.
2. Record the drive's current parameter set using DriveMonitor (USS) or by reading parameter r060 on the PMU.
3. Insert the spare board. Re-seat all connectors and ribbon cables.
4. Power up. Verify PSU1 test-point voltages (see table above).
5. Download the parameter set (P060 = 2). Run the drive in open-loop (P100 = 1) for 5 minutes without load.
6. Apply a 50 % load step. Verify F005 (I²t) does not trip within 60 seconds.
7. Sign off the swap with the date, spare-part serial number, and the installing engineer's signature in the maintenance log.

Troubleshooting Matrix: Drive Symptom to Spare-Part

FAQ