1FK7042-5AF71-1EG3-2 is a compact permanent magnet synchronous servo motor from Siemens SIMOTICS S series, designed for high-performance automation and motion control systems, and fully compatible with the SINAMICS S120 drive system.
| Segmento de modelo | Descrição |
| 1FK7 | Motor series: 1FK7 compact permanent magnet synchronous servo motor, natural cooling |
| 42 | Motor size: shaft height 42 milímetros, corresponding to 3 Nm rated torque class |
| 5AF71 | Design and specification: 5AF = standard design; 71 = mounting dimensions and cooling method (natural cooling) |
| 1EG3 | Encoder and options: E = encoder type; G3 = specific encoder configuration (with DRIVE-CLiQ interface) |
| 2 | Additional feature: usually indicates electromagnetic brake to prevent shaft movement during power loss |
- Parâmetros técnicos principais
| Item | Especificação |
| Rated torque | 3.0 Nm (100K temperature class) |
| Potência nominal | 0.82 kW (1.1 HP) |
| Rated speed | 3000 rpm |
| Corrente nominal | 1.95 UM |
| Método de resfriamento | Resfriamento natural (no external fan required) |
| Tipo de montagem | IM B5 (IM V1, IM V3) – flange mounting |
| Classe de proteção | Standard IP65 (IP64 at shaft end); higher protection optional |
| Tipo de codificador | Codificador absoluto (identified by 1EG3), with DRIVE-CLiQ interface |
| Connector feature | Power/signal connectors rotatable through 270° for easy wiring |
| Rotor inertia | Low-inertia design for improved dynamic response |
| Peso | Aprox.. 4.9–5.0 kg (without brake) |
| Number of pole pairs | 4 |
- Key Features and Advantages
- High-performance permanent magnet design: Uses rare-earth permanent magnets for high power density, high efficiency and low energy consumption.
- High overload capability: Withstands short-term overload above 3x rated torque to adapt to dynamic load changes.
- Precise control: Achieves high-precision positioning and speed control with SINAMICS S120 drives.
- Brake function: Suffix “2” means electromagnetic brake, suitable for vertical axes or gravity-loaded applications to prevent dropping when powered off.
- Instalação flexível: IM B5 flange mounting, rotatable connectors, adaptable to various mechanical layouts.
- Reliability and durability: Proteção IP65, adequado para ambientes industriais agressivos, long bearing life.
- Diagnostic function: Provides comprehensive motor status monitoring and diagnostics via DRIVE-CLiQ.
- Aplicações Típicas
- Linhas de produção automatizadas: Precise control of conveyors, positioning stages, assembly machinery.
- Robotics: Joint drives, end-effector positioning, especially applications requiring position retention at power loss.
- Máquinas de embalagem: High-speed, precise control of paper feeding, bag making, sealing, etc..
- Printing equipment: Register accuracy control, web tension regulation.
- Máquinas-ferramentas: Feed and spindle drives for CNC milling machines, lathes.
- Semiconductor equipment: Manuseio de wafer, positioning platforms requiring high cleanliness and precision.
- Equipamento médico: Precise motion control for diagnostic and therapeutic devices.
- Model Comparison within the Same Series
| Modelo | Principal diferença | Aplicativo |
| 1FK7042-5AF71-1EG0 | Without brake | Horizontal axis, non-gravity load |
| 1FK7042-5AF71-1EG3 | With brake (this model) | Vertical axis, gravity load, position retention required at power loss |
| 1FK7042-5AF71-1EG5 | Different encoder resolution | Applications requiring higher positioning accuracy |
| 1FK7042-5AF71-1GG5 | Basic absolute encoder (32 P/REV) | Cost-sensitive applications with moderate accuracy requirements |
| 1FK7042-5AF71-1FA0 | Codificador absoluto (2048 P/REV) | High-precision positioning applications |
- Drive Compatibility and Replacement Solutions
- Recommended drive: Série SINAMICS S120, perfectly matched to 1FK7 series characteristics.
- Alternative models:
Siemens replacement: 1FT7042 series (mechanically compatible, desempenho semelhante)
Third-party alternatives: Schneider LXM series, ABB ACS series, Mitsubishi MR-J series (observe parameter matching)
- Caminho de atualização: Para maior desempenho, consider 1FK7060 (5 Nm) or 1FK7080 (8 Nm).
- Diretrizes de instalação e manutenção
- Pre-installation checks:
Confirm compatibility between motor and drive system.
Inspect motor appearance and shaft condition.
Verify encoder type and interface.
- Precauções de instalação:
Ensure flatness during flange mounting to avoid eccentric load.
Rotate connectors to optimal wiring position (máx.. 270°).
Correctly connect brake wiring to the brake control terminal of the drive.
- Maintenance recommendations:
Regularly check motor temperature (normal operating temperature < 85 °C).
Keep motor clean to avoid dust buildup affecting heat dissipation.
Periodically verify brake operation for reliable holding when de-energized.
Protect encoder cables from strong electromagnetic interference.
1FK7042-5AF71-1EG3-2 is a 3 Nm compact permanent magnet synchronous servo motor from Siemens SIMOTICS S series, equipped with absolute encoder and brake, naturally cooled. It is ideal for industrial automation applications requiring high-precision positioning and position retention at power loss.
With low inertia and high overload capability, it performs excellently in high dynamic response applications, and achieves outstanding motion control performance with the SINAMICS S120 drive system.
Siemens 1FK7042 Series Servo Motor: Complete Coding System and Cross-Brand Alternatives
- Full Model Naming Convention
Each segment of 1FK7042-XXXXX-XXXX-X has a clear meaning that defines core properties and configuration:
| Segmento | Código | Descrição |
| 1FK7 | Fixed prefix | Siemens SIMOTICS S compact PMSM, natural cooling |
| 42 | Size code | Shaft height 42 milímetros, 3 Torque nominal Nm; 04 = shaft height, 2 = length class |
| XX | Design type | 2A = standard compact |
| 3B = high inertia | ||
| 5A = compact (510V–720V) | ||
| 2C = high dynamic | ||
| F71 | Resfriamento & montagem | F = standard flange; 7 = with connector; 1 = natural cooling |
| 1XX | Tipo de codificador | 1E = absolute (DRIVE-CLiQ) |
| 1F = incremental | ||
| 1P = resolver | ||
| 1Q = absolute 20-bit single-turn | ||
| 1R = absolute 24-bit single-turn + 12-bit multi-turn | ||
| X | Additional feature | 0 = no brake |
| 2 = with electromagnetic brake | ||
| 3 = special protection | ||
| 5 = with incremental encoder | ||
| X | Interface/accuracy | G3 = DRIVE-CLiQ, high resolution |
| A0 = standard accuracy | ||
| H2 = with mechanical brake | ||
| U0 = incremental encoder (±1 pulse accuracy) |
- Complete 1FK7042 Model List (by Configuration)
2.1 Standard Compact (2A/5A) Basic Configurations
| Modelo Completo | Configuração principal | Aplicativo |
| 1FK7042-2AF71-1AG0 | 3Nm, 3000rpm, 0.82kW, incremental encoder, sem freio | Horizontal drive, general positioning accuracy |
| 1FK7042-2AF71-1QG0 | 3Nm, 3000rpm, 0.82kW, 20-bit single-turn absolute encoder, sem freio | High-precision positioning, position memory at power loss |
| 1FK7042-2AF71-1RB0 | 3Nm, 3000rpm, 0.82kW, 24-bit single-turn +12-bit multi-turn absolute encoder, sem freio | Multi-axis linkage, complex motion control |
| 1FK7042-5AF71-1EG3-2 | 3Nm, 3000rpm, 0.82kW, codificador absoluto (DRIVE-CLiQ), com freio | Vertical axis, gravity load, anti-drop at power loss |
| 1FK7042-5AF71-1FH3 | 3Nm, 3000rpm, 0.82kW, incremental encoder, com freio | High-speed reciprocating motion, high dynamic response |
| 1FK7042-2AF71-1PA0 | 3Nm, 3000rpm, 0.82kW, resolver, sem freio | Harsh EMI environment, high anti-interference requirement |
| 1FK7042-2AF71-1CB0 | 3Nm, 3000rpm, 0.82kW, codificador absoluto, special protection | Dust/moist environment, IP67 |
2.2 Alta Inércia / High-Dynamic Special Configurations
| Modelo Completo | Configuração principal | Aplicativo |
| 1FK7042-3BK71-1QH2 | 3Nm, 3000rpm, 0.9kW, high inertia, codificador absoluto, com freio | Large inertia matching, smooth start/stop |
| 1FK7042-2AC71-1QA0 | 3Nm, 6000rpm, 1.8kW, high dynamic, codificador absoluto, sem freio | High-speed positioning, resposta rápida |
| 1FK7042-2AK74-1TH0 | 3Nm, 6000rpm, 0.9kW, compactar, resolver, com freio | High-speed motion, anti-interference required |
- Mainstream Brand Alternatives (3 Nm Class)
3.1 Siemens Internal Replacements
| Original | Alternativa | Compatibilidade |
| 1FK7042-5AF71-1EG3-2 | 1FT7042-5AF71-1CH1-Z N05 | Fully mechanical compatible, mesmo desempenho, same encoder interface |
| 1FK7042-2AF71-1QG0 | 1FK7042-5AF71-1QH0 | Optimized voltage range, otherwise identical |
| 1FK7042-2AF71-1PA0 | 1FK7042-5AF71-1PH0 | Upgraded resolver interface, improved protection |
3.2 Schneider Elétrica
| Alternativa | Número do pedido. | Principais parâmetros de correspondência |
| BCH2MF0733CA1C | 140S-M-0733 | 3Nm, 3000rpm, 0.85kW, codificador absoluto, com freio |
| LXM32AD18M2+BSH0701P01A2A | 9020-0701 | Drive+motor set, 3Nm, 3000rpm, compatible with SINAMICS environment |
3.3 ABB
| Alternativa | Número do pedido. | Principais parâmetros de correspondência |
| MotiFlex e180+M3AA08060HB | 3ABD00012600 | 3Nm, 3000rpm, 0.82kW, codificador absoluto, com freio |
| ACS880-01-040A-5+MQM0804-0300 | 3AXD50000038924 | Drive+motor set, fits 1FK7 mounting dimensions |
3.4 Mitsubishi
| Alternativa | Número do pedido. | Principais parâmetros de correspondência |
| MR-J4-350B+HF-KP43 | MR-J4-350B+HF-KP43B | 3.5Nm (compatible with 3Nm), 3000rpm, codificador absoluto, com freio |
| MR-J5-350B+HF-KP43B | MR-J5-350B+HF-KP43B | New generation, optimized communication, ~15% performance boost |
3.5 OMRON
| Alternativa | Número do pedido. | Principais parâmetros de correspondência |
| R88M-G30030H-S2-Z | R88M-G30030H-S2-Z | 3Nm, 3000rpm, 0.8kW, codificador absoluto, com freio |
| 1S Series + R88D-1SN03H-ECT | 1S030-30CB2-D + R88D-1SN03H-ECT | Integrated safety, Certificado SIL3, for harsh industrial environments |
- Key Guidelines for Replacement Selection
- Parameter matching priority:
Rated torque (3 Nm) > Rated speed (3000 rpm) > Poder (0.82 kW) > Rotor inertia > Classe de proteção
Encoder type must match the system (absoluto / incremental / resolver)
Brake (sufixo 2) is mandatory for vertical axes.
- Compatibilidade mecânica:
Match flange (IM B5), shaft diameter, keyway to original equipment.
Connectors rotatable 270° for wiring convenience.
Brake wiring must match drive brake control terminals.
- Drive compatibility:
Siemens SINAMICS S120 works natively with 1FK7/1FT7.
Third-party drives must support the encoder interface (DRIVE-CLiQ / SSI / incremental).
Same-brand drive-motor combinations are recommended to minimize issues.
The 1FK7042 series is the core 3 Nm torque class product in the Siemens SIMOTICS S family.
With various encoder, brake and protection configurations, it covers standard industrial to harsh environment applications.
When selecting replacements, prioritize matching torque, velocidade, encoder type and mounting dimensions, while ensuring drive compatibility and long-term supply stability.
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