SIMOVERT P 6SE4821-3FB10: Manual, Parameters & Profibus Setup

SIMOVERT P 6SE4821-3FB10 Drive Identification and Family Context

The 6SE4821-3FB10 is a member of the SIMOVERT P variable-frequency AC drive family manufactured by Siemens in the late 1980s and early-to-mid 1990s. The SIMOVERT P series was the mainstream inverter family positioned between the earlier SIMOVERT 6SE12 analog series and the subsequent SIMOVERT Masterdrives (6SE70/6SE71) generation. It served pumps, fans, conveyors, extruders, and general-purpose industrial machines in European and export markets.

The drive uses a microcontroller-based V/Hz and sensorless vector control architecture with an IGBT output stage in later production lots and is now classified as a discontinued product. Spare-parts support is limited to remanufactured control boards and donor units, and Siemens' official guidance is to migrate to a current-generation SINAMICS platform for new installations and major retrofits. Drive tools available on the Siemens Industry Online Support portal target only Masterdrives and SINAMICS, not SIMOVERT P.

Catalog Number Decoding

The exact power-class mapping for the trailing order code is documented in the family DTR. For engineering purposes, treat 6SE4821-3FB10 as a 5.5 kW / 12 A class unit at 400 V three-phase until the nameplate confirms otherwise.

Technical Specifications

The table below consolidates field-reported and family-typical values. Where the source is ambiguous (for example, a current value originates from a single field report of one SIMOVERT P unit, not necessarily the exact 6SE4821-3FB10), the value is flagged as field-reported.

Front-Panel Layout and Indicators

Operator Panel (PMU) Operation

The PMU is the integrated parameterization unit on the front of the SIMOVERT P drive. It consists of a 4-digit 7-segment display and three keys:

• P key — Selects parameter number; press to enter value-edit mode.
• ▲ — Increment parameter number, or increment value while editing.
• ▼ — Decrement parameter number, or decrement value while editing.

To read parameters, press P and use ▲/▼ to scroll to the parameter number; press P again to display the value. To write, change the value with ▲/▼ and hold P for 2 seconds to commit to EEPROM. Cycling control power does not erase stored values.

PMU Display States

PMU Reset and Restore Defaults

1. Power down the drive; wait 5 minutes for DC bus discharge (verify with a category-rated multimeter at the DC+ / DC- test points — must read below 50 V DC before touching anything).
2. Power up while holding P + ▲ simultaneously.
3. Display shows FAC; release keys.
4. Press P to confirm factory-restore; the drive reloads all parameters to default.
5. Re-enter motor nameplate data and any application-specific parameters from your snapshot log.

Serial Interface (RS485) Wiring

The 6SE4821-3FB10 exposes a 2-wire RS485 interface on the control board, internally intended for peer-to-peer (P-to-P) and USS-bus communication. There is no native USB, RS232, or Ethernet port. The connector is typically a 9-pin D-sub or a 5-pin terminal block, depending on hardware revision.

RS485 Pin Reference (typical)

USS Protocol Frame

SIMOVERT P uses the Siemens USS protocol (Universal Serial Interface) over RS485. USS is a master/slave polling bus where one master (PLC or PC) addresses each drive in turn by slave address.

Telegram layout (read parameter, master → slave):
+--------+------+------+------+------+------+------+------+------+
|  STX   | LGE  | ADR  | PKE  | IND  | PWE  | STW  | HSW  | BCC  |
+--------+------+------+------+------+------+------+------+------+
   02h     0Ch    01h    0001h  0000h  0000h  0000h  0000h   XOR

• STX (02h): Start byte.
• LGE: Telegram length in bytes (excluding STX, BCC). For SIMOVERT P the fixed length is 0Ch.
• ADR: Slave address (0x01..0x1E for drives 1..30).
• PKE: Parameter identifier; bit 15 = read/write, bits 14-12 = reserved, bits 11-0 = parameter number.
• IND: Index / sub-parameter (typically 0000h for SIMOVERT P).
• PWE: Parameter value (16-bit; some drives double this for 32-bit).
• STW / HSW: Control word and main setpoint from master to slave (drive-side: status and actual value).
• BCC: XOR checksum of all preceding bytes.

The default baud rate is 9600 bps; 19200 and 38400 are selectable via parameter P0xx (depending on revision). For diagnostic tracing, a USB-RS485 converter with COM-port sniffer (such as the open-source ser2net or a commercial terminal) lets you observe the bus while the master is polling.

Profibus Communication Card (IM 308 B / S5 only)

The SIMOVERT P family accepts an optional Profibus DP communication card that plugs into the drive's expansion connector. The card implements a Profibus DP slave with parameter-channel access and process-data exchange (PZD) for control word, status word, setpoint, and actual value.

Why IM 308 B Only?

The IM 308 B is the SIMATIC S5-era Profibus DP master with a specific GSD file naming and parameter-access convention. The SIMOVERT P Profibus card's GSD, parameter slot assignments, and process-data mapping were frozen against the IM 308 B's expectations in the early 1990s.

Subsequent S7 Profibus masters use a different parameter-channel structure (PKW with double-word indices vs SIMOVERT P's word-only PKW). Even though the physical Profibus layer is identical, the parameterization handshake does not match, and the SIMOVERT P card will fail to enumerate on an S7 master with diagnostic "slave not found" or "parameterization fault" errors.

If a site still uses a SIMATIC S5-115U, S5-135U, or S5-155U with IM 308 B master, the integration works. S5 hardware is itself discontinued, and Siemens' service window for S5 spare parts ended years ago, so this combination is itself a brownfield concern.

Recommended Replacement Path for the Profibus Card

For installations where Profibus integration is required but no S5 master is available, replace the SIMOVERT P Profibus card with a current Siemens drive that supports Profinet or EtherNet/IP. Modern SINAMICS G120 control units (CU240E-2 PN, CU250S-2 PN) support both Profinet and Profibus via their onboard interfaces, and the standard GSD files integrate with S7-1500 / S7-1200 Profinet masters directly. See the SINAMICS G120 documentation set on Siemens Industry Online Support.

Parameter List (~50 Parameters)

The SIMOVERT P drive exposes roughly 50 user-accessible parameters. This compact parameter set is one of the reasons the drive can be fully documented by hand, without a PC tool: a commissioning engineer can record the entire configuration in 30-45 minutes via the PMU and a written log.

Parameter Categories

Critical Parameters to Capture First

When recording a parameter snapshot for migration or service, prioritize these values because they are required for any replacement drive:

1. Motor rated voltage — typically 400 V at 50 Hz; 460 V at 60 Hz.
2. Motor rated current — must match the motor nameplate within 5%.
3. Motor rated power — 5.5 kW for the class of the 6SE4821-3FB10.
4. Motor rated frequency — 50 or 60 Hz.
5. Motor rated speed — typically 1450 rpm at 50 Hz / 1750 rpm at 60 Hz for a 4-pole motor.
6. Ramp-up / ramp-down time — application-specific.
7. Current limit — typically 150% of motor rated current.
8. Control mode — V/f linear, V/f quadratic, or sensorless vector.
9. Switching frequency — affects acoustic noise and motor heating.
10. Communication parameters — USS address, baud rate, Profibus node address.

Sample Parameter Snapshot Procedure

1. Apply control voltage; leave power stage inhibited (enable terminal open).
2. Wait for the PMU to show --- or 0.0 without rotation.
3. Press P to enter parameter display; use ▲/▼ to scroll to P000.
4. Press P to read value; write value to log.
5. Repeat for P001..P059.
6. For each parameter where the value is application-specific, mark an asterisk (*) in the log so the migration engineer knows it must be re-entered.
7. Print the log, sign and date it, and tape it to the inside of the cabinet door.

Parameterization Software Compatibility

Modern Siemens drive commissioning tools do not support the 6SE4821-3FB10. The drive uses a USS-protocol parameter model that predates the STARTER / Drive ES data structure.

Software Compatibility Matrix

If PC-based parameterization is required today, only legacy SimoCom A or SimoCom P tools support this generation. These can sometimes be located on industrial-software archive sites but are unsupported by Siemens. New commissioning work should rely on the PMU for the 6SE4821-3FB10.

For reference, current Siemens drive tools are documented at the Siemens Industry Online Support portal. The current Drive ES Basic package is available from Siemens support with a valid support contract; it does not include SIMOVERT P support.

Original Documentation Sources

The SIMOVERT P Documentation Technique de Référence (DTR) was originally distributed as a paper document and later as PDF and CD-ROM. The DTR is the primary reference for parameter descriptions, fault codes, wiring diagrams, and commissioning procedures.

• DTR manual (English): The family DTR (filename pattern 6SE21_Simovert_P_DTR_en.pdf) covers most of the SIMOVERT P parameter set and is the closest freely-circulated English reference. Specific 6SE4821-3FB10 details must be cross-checked against the variant's order code.
• Operating Instructions (BA): Shorter commissioning guide covering PMU usage, motor data entry, and fault list. Typically 40-80 pages.
• List Manual: Parameter-by-parameter description with value ranges, defaults, and access levels. The most useful reference for migration engineers.
• Spare-parts list (SL): Component-level BOM for board replacement, including the Profibus card and the PMU.

Voltage and Current Measurement Points

For commissioning and field service, the SIMOVERT P provides several test points for measurement with a handheld multimeter or oscilloscope. These points are accessible without opening the drive.

Modernization Path to SINAMICS / Masterdrives

Siemens' official recommendation is to replace the SIMOVERT P with a current-generation drive. Three replacement families are commonly considered, depending on application requirements.

For information on current SINAMICS documentation and firmware, refer to the SINAMICS G120 operating instructions on the Siemens Industry Online Support portal.

Migration Step-by-Step (SIMOVERT P → SINAMICS G120)

1. Capture the SIMOVERT P parameter snapshot via the PMU (procedure above). Save to a paper record and a CSV file.
2. Select the SINAMICS G120 frame size: for 5.5 kW at 400 V, frame size FSA (0.55-1.5 kW) is too small; FSB (2.2-4 kW) is borderline; FSC (5.5-7.5 kW) is the right choice.
3. Map parameters from SIMOVERT P to SINAMICS G120:

4. Wire the SINAMICS G120 using the existing control cable bundle. The CU240E-2 has DI0..DI5, AI0..AI1, DO0..DO2, AO0..AO1, and onboard Profinet. Most control wiring maps 1:1 from the SIMOVERT P terminal block.
5. Verify motor rotation direction by jogging in V/f mode (P1300=0) at 5 Hz (P1082=5 Hz) before enabling the full control loop.
6. Run autotuning: set P1900=1 for static measurement (motor does not rotate), or P1900=2 for rotating measurement (motor accelerates; ensure safe clearance).
7. Test fault response by simulating a mains dip or by triggering STO; verify the SINAMICS trips correctly and latches the fault code in r0947.
8. Validate with the connected PLC: if the original installation used a SIMATIC S5, the migration will also require a controller upgrade (typically to S7-1500 or ET 200S with Profinet).
9. Save the migrated parameter set as a STARTER / Startdrive project on a backup medium. File with the cabinet documentation.

When Migration Is Not Possible

Some brownfield applications — mining, marine, remote oil-and-gas, defense — cannot migrate immediately. For these cases:

• Maintain a stock of refurbished SIMOVERT P units as cold spares. Donor boards from decommissioned drives are an acceptable source of control boards and PMUs.
• Document every parameter offline (the snapshot procedure above). Tape the printout inside the cabinet door.
• Engage a Siemens Solution Partner with SIMOVERT service capability for repair. Several third-party repair houses in Germany, Italy, and the UK still service 6SE48 drives.
• Schedule a one-time parallel retrofit: install a current Masterdrives or SINAMICS G120 next to the SIMOVERT P, then switch over once validated.

Safety Considerations

• Lockout/tagout before opening the cabinet. Verify zero energy at the supply disconnect.
• DC bus discharge time: wait at least 5 minutes after power-off before touching internal components. Measure DC+ / DC- with a category-rated multimeter; the bus must read below 50 V DC.
• Stop functions: STO (Safe Torque Off) is not natively implemented on the SIMOVERT P family. Safety stops must be implemented by a contactor in the motor supply.
• Motor insulation: before commissioning a motor that has been stored or rewound, perform an insulation test (megger at 500 V DC) to ground. Inverter-duty motors with peak voltage withstand ≥ 1500 V are recommended.
• EMC: install the drive in a cabinet with proper bonding (paint removed at mounting points). Use shielded motor cable, with shield grounded at both ends via 360° glands.

Troubleshooting Matrix

Fault Code Reference

Common faults on the SIMOVERT P family, mapped to typical fault numbers. The exact code on a 6SE4821-3FB10 may differ — cross-reference against the unit's specific DTR List Manual.

Field-Commissioning Checklist

1. Verify supply voltage matches the nameplate (e.g., 400 V 3-phase, ±10%).
2. Confirm control wiring (enable, direction, analog input) before power-up.
3. Read all parameters; record baseline to the snapshot log.
4. Run motor open-loop at low frequency; verify rotation direction with a phase-rotation meter or by visual inspection of the driven load.
5. Run ramp test: full speed forward, ramp down to zero, full speed reverse, ramp to zero. Observe motor current throughout; the displayed current must stay below the current limit.
6. Trigger a known fault (e.g., remove the enable terminal while running) and verify fault indication on the PMU.
7. Reset fault via the PMU; verify the drive returns to the ready state.
8. If Profibus is fitted, verify the slave is visible in the IM 308 B diagnostic buffer (S5 only). The slave must appear with status "Data Exchange."
9. Save the parameter snapshot; print, sign, date, and file with the cabinet.

Symptom-Based Diagnostic Flowchart

Common symptoms and where to start:

Frequently Asked Questions