Inovance SV660N Series Servo Drive Manual User Guide: A Comprehensive Technical Analysis of the EtherCAT Bus Servo
Introduction
In the field of industrial automation, the selection and application of servo drives directly determine motion control precision and production efficiency. Inovance Technology has established the SV660 series servo drives as widely adopted solutions, with the SV660A and SV660P variants serving distinct application scenarios. However, as industrial Ethernet technology rapidly proliferates, market demand for EtherCAT bus-based servo drives has grown significantly, giving rise to the SV660N series. Unlike the SV660A and SV660P, the SV660N series is architecturally designed from the ground up for EtherCAT bus communication. Its parameter system, control modes, and terminal configurations are all built around the EtherCAT protocol, endowing it with unique advantages in multi-axis coordinated control, semiconductor manufacturing, surface mount technology (SMT) equipment, printed circuit board drilling machines, and other high-precision applications.
This article is based on the SV660N Series Servo User Manual (Document Code: PS00005512, Version B06). It provides a systematic overview covering product overview, operation panel, wiring terminals, control modes, fault diagnosis, and maintenance, helping engineers quickly master the core technical aspects of this product line and avoid common pitfalls during commissioning.
1. SV660N Product Overview and Model Differentiation
1.1 Product Positioning and Core Features
The SV660N series is a high-performance, small-to-medium power AC servo product developed by Inovance Technology, with a power range covering 0.05kW to 7.5kW. The most distinctive feature of this series is its Ethernet communication interface with full support for the EtherCAT communication protocol, enabling multi-drive networked operation with a host controller. The compatible MS1-R series servo motors offer both low-inertia and medium-inertia options, equipped with 23-bit single-turn absolute encoders or 23-bit multi-turn absolute encoders, ensuring quiet and smooth operation.
The SV660N series provides rigidity table settings, inertia identification, and vibration suppression functions, making the servo drive straightforward to commission. It is suitable for semiconductor manufacturing equipment, SMT machines, PCB drilling machines, material handling machinery, food processing machinery, machine tools, conveyor systems, and other automated equipment requiring fast and precise coordinated control.
1.2 Model Naming Convention
The SV660N model number contains six key information segments. Correctly interpreting the model is fundamental to proper selection and usage:
| Segment | Meaning | Example Values |
|---|---|---|
| 1: Product Series | SV660 series servo drive | SV660 |
| 2: Product Type | N = EtherCAT communication type | N |
| 3: Voltage Class | S = 220V, T = 380V | S / T |
| 4: Rated Output Current | Current value code | 1R6=1.6A, 2R8=2.8A, 5R5=5.5A, 7R6=7.6A, 012=11.6A, 3R5=3.5A, 5R4=5.4A, 8R4=8.4A, 017=16.5A, 021=20.8A, 026=25.7A |
| 5: Mounting Method | I = Base mounting | I |
| 6: Non-standard Function | Special function identifier | Blank=Standard, FS=STO Safety, NS=Upgraded, FH=High Protection, INT=International |
For example, model “SV660NS7R6I” denotes: SV660 series, EtherCAT communication type, 220V voltage class, rated current 7.6A, base mounting, standard drive.
1.3 Drive Size Classification and Power Ratings
The SV660N is classified into five Size levels based on physical dimensions and power rating:
- Size A (0.2kW to 0.4kW): Models S1R6, S2R8; natural cooling; no built-in braking resistor
- Size B (0.75kW): Model S5R5; single-phase 220V input; forced air cooling; built-in 50-ohm/50W braking resistor
- Size C (1.0kW to 1.5kW): Models S7R6 (220V), T3R5/T5R4 (380V); supports single-phase and three-phase input
- Size D (1.5kW to 3.0kW): Models S012 (220V), T8R4/T012 (380V)
- Size E (5.0kW to 7.5kW): Models T017/T021/T026; three-phase 380V input; features external reactor terminals N1/N2
1.4 Differences Between SV660N and SV660N-NS Upgraded Version
The manual appendix details 35 differences between the standard SV660N and the upgraded SV660N-NS, representing a unique product differentiation strategy within the SV660N series. Key differences include:
| Difference | SV660N (Standard) | SV660N-NS (Upgraded) |
|---|---|---|
| Fault record count | 10 groups | 20 groups |
| Black box trigger mode | Single trigger only | Continuous trigger supported |
| Communication port LED indicator | None | Network indicator LED present |
| Ring topology support | Supported | Not supported |
| Field weakening capability | Max demagnetization current 200% | Max demagnetization current 300% |
| STO E150.4 detection | Checked once at power-on | Continuously monitored during operation |
| Backend homing function | Not available | Newly added |
| Power-loss stop method | Default: disable stop | Three options: fault stop, disable stop, quick stop (H02.17) |
| EtherCAT sync mode (H0E.31) | Default 1 (no command estimation on frame loss) | Default 2 (command estimation enabled on frame loss) |
| EtherCAT sync error threshold (H0E.32) | 3000ns | 4000ns |
These differences indicate that the SV660N-NS has been comprehensively enhanced in fault diagnosis capability, communication robustness, and safety function monitoring, making it suitable for applications with higher reliability requirements. Notably, the standard SV660N supports ring topology — connecting the OUT port of the last servo in the network back to the PLC master enables redundant communication: if any servo in the network goes offline, other servos remain unaffected. This is a unique redundancy design advantage of the SV660N.
2. Operation Panel and Parameter Settings
2.1 Panel Composition
The SV660N operation panel consists of a 5-digit 8-segment LED display and five pushbuttons. The button functions are as follows:
- MODE: Cycle through function codes
- Up triangle: Increase the blinking digit value
- Down triangle: Decrease the blinking digit value
- Left arrow: Shift the blinking digit left (long press: page through when display exceeds 5 digits)
- SET: Save changes and enter the next-level menu
2.2 Parameter Group System
SV660N parameters use a group-coded system, expressed in “H + group number + parameter number” format. The functional positioning of each parameter group is as follows:
| Group | Function | Typical Parameters |
|---|---|---|
| H00 | Servo motor parameters | Motor model, encoder type |
| H01 | Drive parameters | Drive model, rated specifications |
| H02 | Basic control parameters | Control mode selection, stop method |
| H03 | Terminal input parameters | DI function assignment, logic selection |
| H04 | Terminal output parameters | DO function assignment, EtherCAT forced DO |
| H05 | Position control parameters | Electronic gear ratio, position feedforward |
| H06 | Speed control parameters | Speed loop gain, speed limit |
| H07 | Torque control parameters | Torque limit, friction compensation |
| H08 | Gain parameters | Position loop gain, speed loop gain |
| H09 | Auto-tuning parameters | ETune/STune auto-tuning |
| H0A | Fault and protection parameters | Overload protection, overspeed threshold |
| H0b | Monitoring parameters | Run status monitoring, fault records |
| H0E | Communication function parameters | EtherCAT configuration, sync mode |
Additionally, the SV660N uses EtherCAT object dictionary parameters (1000h group and 6000h group) that follow the CiA 402 specification and are accessible via SDO. For example, control word 6040h and status word 6041h are the core interfaces of the servo state machine, 6060h is used for mode selection, and 6061h returns the actual operating mode.
2.3 Key Parameter Setting Points
In EtherCAT bus applications, the following parameter settings are particularly critical:
- H0E.31 (EtherCAT sync mode): Standard type defaults to 1, no command estimation on CSP frame loss; NS upgraded version defaults to 2, enabling command estimation on frame loss for improved communication robustness
- H0E.32 (Sync error threshold): Standard type 3000ns, NS version 4000ns; triggers an alarm when sync error exceeds this threshold
- H02.17 (Power-loss stop method): NS version only; supports fault stop, disable stop, or quick stop methods
- H04.22 (DO source selection): NS version only; selects between communication-sourced and non-communication-sourced (local DO, position compare, 402 forced DO)
- H0E.07 (Object dictionary unit selection): NS version only; supports selection between command unit system and user unit system
When the synchronization cycle needs to support 125 microseconds, the manual specifically notes that the command scheduling frequency must be modified to 8kHz, which is critical for high-response applications.
3. Wiring and Terminal Definitions
3.1 Terminal Overview
The SV660N terminal layout reflects the design philosophy of an EtherCAT bus servo. Terminal functions are as follows:
| Terminal | Function | Description |
|---|---|---|
| CN1 | Control terminal | DI/DO command input/output signal port |
| CN2 | Encoder terminal | Connects to motor encoder; supports 23-bit absolute encoder |
| CN3 | EtherCAT IN | Connects to master or upstream slave device |
| CN4 | EtherCAT OUT | Connects to downstream slave device |
| CN5 | RS232 communication | Connects to debugging software or RS232 command device |
| CN6 | STO safety terminal | Functional safety signal input (FS models only) |
| L1/L2/L3 | Main circuit power | 220V class: single or three-phase; 380V class: three-phase |
| L1C/L2C | Control circuit power | Size C and above: independent control power input |
| U/V/W | Motor connection | Servo motor three-phase connection |
| P+/D/C | Braking resistor | Keep P+-D shorting bar for built-in resistor; remove and connect external resistor between P+ and C |
| P+/N- | DC bus | For common DC bus operation across multiple drives |
| N1/N2 | External reactor | Size E only; shorted by default; remove shorting bar and connect DC reactor for harmonic suppression |
3.2 EtherCAT Communication Wiring Essentials
EtherCAT communication wiring is the core differentiator between the SV660N and the SV660A/SV660P. CN3 (IN) and CN4 (OUT) use standard RJ45 interfaces, supporting both line and ring topologies. The manual states that the standard SV660N supports ring topology — connecting the OUT port of the last servo back to the PLC master enables redundant communication. If any servo in the network goes offline, other servos remain unaffected. The NS upgraded version does not support ring topology.
Communication cable installation notes:
- Use cables meeting the manual’s specifications; ensure reliable shield grounding
- Observe cable bend radius requirements to prevent damage
- Use shielding brackets to secure communication cables and reduce EMI
- When troubleshooting EtherCAT interference, focus on shield grounding, cable routing away from power lines, and magnetic clamp installation
3.3 Main Circuit Wiring Notes
- Size A (S1R6/S2R8) has no built-in braking resistor; connect external resistor between P+ and C if needed
- S5R5 is single-phase 220V input; power is connected only at L1 and L2
- S7R6 and S012 can accept single-phase or three-phase main power; for single-phase, connect L1 and L2 without derating
- Size E (T017 and above) has a default shorting bar between N1/N2; remove it and connect a DC reactor for harmonic suppression
- All shielded cable shields must be grounded at a single point reliably
- Tighten terminal screws to the torque values specified in the manual; insufficient or excessive torque may cause overheating or damage
3.4 DI/DO Signal Function Definitions
SV660N DI/DO signal functions are assigned via function codes. Common functions are listed below:
Digital Input (DI) Function Codes:
- FunIN.1 (S-ON): Servo enable; effective only in non-bus control mode
- FunIN.2 (ALM-RST): Alarm reset signal; effective only in non-bus control mode
- FunIN.14 (P-OT): Positive overtravel switch; prohibits forward drive when active
- FunIN.15 (N-OT): Negative overtravel switch; prohibits reverse drive when active
- FunIN.31 (HomeSwitch): Home switch
- FunIN.34 (Emergency Stop): Emergency stop; zero-speed stop with position lock when active
- FunIN.38 (TouchProbe1): Touch probe 1; logic depends only on 60B8h
- FunIN.39 (TouchProbe2): Touch probe 2
Digital Output (DO) Function Codes:
- FunOUT.1 (S-RDY): Servo ready
- FunOUT.2 (TGON): Motor rotation signal; active when speed reaches H06.16 setting
- FunOUT.5 (COIN): Positioning complete
- FunOUT.9 (BK): Brake output
- FunOUT.10 (WARN): Warning
- FunOUT.11 (ALM): Fault
- FunOUT.18 (ToqReach): Torque reached
- FunOUT.25 (CMP): Position compare DO
- FunOUT.32 (EDM): EDM safety status; outputs active signal only when both STO1 and STO2 24V inputs are simultaneously disconnected
4. Control Modes and Commissioning
4.1 Seven Control Modes
The SV660N supports seven control modes defined by the CiA 402 specification, representing the standard capability of an EtherCAT bus servo:
| Mode | Name | Characteristics |
|---|---|---|
| CSP | Cyclic Synchronous Position | Master sends periodic position commands; distributed clock synchronization; suitable for high-precision multi-axis coordination |
| CSV | Cyclic Synchronous Velocity | Master sends periodic velocity commands |
| CST | Cyclic Synchronous Torque | Master sends periodic torque commands |
| PP | Profile Position | Drive-internal trajectory planning; master sends target position |
| PV | Profile Velocity | Drive-internal velocity planning |
| PT | Profile Torque | Drive-internal torque planning |
| HM | Homing | Supports multiple homing methods; establishes absolute coordinate system upon completion |
The three cyclic synchronous modes (CSP/CSV/CST) are the core application modes of the SV660N as an EtherCAT bus servo, achieving microsecond-level synchronization through distributed clocks — a capability that the SV660A/SV660P pulse/analog control methods cannot achieve.
4.2 Servo State Machine and Control Word
The SV660N follows the CiA 402 state machine specification, driving state transitions via control word 6040h and reading the current state via status word 6041h. The main states include: Initialization, Not Ready, Ready, Enabled, and Operation. The bit definitions of 6040h vary by mode; for example, bit 8 is used for the pause function in PP mode, and bit 4 is used to start homing in HM mode.
4.3 Commissioning Workflow
The manual recommends the following commissioning workflow:
- Pre-run inspection: Verify secure installation, correct wiring, and matching power specifications
- Power application: Apply control power first, then main power; observe panel display and CHARGE indicator
- JOG operation: Perform JOG test runs via panel or debugging software to confirm motor direction and normal operation
- Parameter configuration: Configure motor parameters (H00 group), control mode (H02 group), and EtherCAT communication parameters (H0E group)
- Inertia identification: Execute offline or online inertia identification to obtain load inertia ratio
- Gain tuning: Use ETune or STune auto-tuning, or manually adjust H08 group gain parameters
- Trial operation: Run under actual operating conditions; observe tracking error and vibration
- Servo stop: Configure stop method per application requirements
4.4 Gain Tuning Methods
The SV660N provides two automatic gain tuning methods and a rich set of manual tuning parameters:
- ETune: Command-response-based auto-tuning; suitable for scenarios with existing motion commands
- STune: Step-response-based auto-tuning; the drive generates its own excitation signal
- Manual gain tuning: H08 group parameters include position loop gain, speed loop gain, speed loop integral time constant, and more. Advanced features include gain switching, position command filtering, feedforward gain adjustment, pseudo-differential feedforward control, torque disturbance observer, model following, speed observer, and friction compensation
4.5 Vibration Suppression Functions
The SV660N provides three levels of vibration suppression capability:
- Vibration suppression: General-purpose vibration suppression
- Mechanical resonance suppression: Suppresses resonance at mechanical structure natural frequencies via notch filters
-
Tip low-frequency suppression Suppresses low-frequency vibration at transmission endpoints (e.g., robotic arm tips) 4.6 Multi-Axis Recipe Management
The SV660N series features a unique multi-axis recipe management function (manual Chapter 15) that allows the host controller to manage parameter recipes for multiple servo drives via the EtherCAT bus, enabling rapid parameter recall during product changeovers. This delivers significant efficiency improvements for automated production lines requiring frequent product model switching, such as semiconductor manufacturing and food packaging.
5. Fault Diagnosis and Alarm Codes
5.1 Fault Classification
The SV660N classifies abnormalities into two levels: faults and warnings. Faults cause the servo to stop, with the panel displaying in “Er.xxx” format; warnings do not cause stopping but display warning information. Both faults and warnings use the “Exxx.x” encoding format, where x is a digit.
5.2 Common Fault Codes
The following table lists key fault codes referenced in the SV660N manual:
Fault Code Fault Name Troubleshooting E101.0 System parameter abnormal Check if system parameters were accidentally modified; try parameter initialization E101.1 H00/H01 group parameter abnormal Check motor and drive parameter groups; verify H00.08 setting E120.0 Unrecognized encoder type Check encoder wiring and encoder type settings E122.0 DI function duplicate assignment Check H03 group DI function assignments for duplicates E122.2 DO function assignment fault Check H04 group DO function assignments E136.0 Encoder ROM motor parameter verification abnormal Check encoder-motor matching E150.0 STO safe state STO function triggered; check CN6 safety signals E150.1 STO input abnormal Check STO1/STO2 dual-channel signal consistency E150.3 STO input circuit hardware diagnosis failure STO front-stage optocoupler detection abnormal; contact manufacturer E150.4 PWM buffer hardware diagnosis failure PWM Buffer chip initialization abnormal; contact manufacturer E201.0 P-phase overcurrent Check motor phase short circuit, drive power module E208.2 Encoder communication timeout Check CN2 encoder cable connection E320.0/E320.1 Newly added faults Added in B02 version; see troubleshooting manual E410.1 Overload fault confirmation Check for excessive load; B04 version modified confirmation method E500.0 Motor overspeed Check H0A.08 overspeed threshold; investigate speed command anomalies E601.0 Homing timeout Check homing signal, limit switches; re-trigger HomingStart to reset E620.0 Motor overload Adjust H0A.04 overload trip time; check load conditions E630.0 Stall overtemperature Adjust H0A.32 detection time threshold; check cooling conditions E731.0 Communication abnormal (hot-plug prohibited) Never hot-plug EtherCAT communication cables E740.0 Encoder cable disconnection (NS version) NS version reports E740.0 when encoder cable is disconnected E740.2 Encoder cable disconnection (standard) Standard version reports E740.2 when encoder cable is disconnected E921.0 Newly added fault Added in B02 version E950.0 Positive overtravel warning Check positive limit switch, H0A.41 soft limit setting E952.0 Negative overtravel warning Check negative limit switch, H0A.43 soft limit setting EE08.2 EtherCAT communication fault Check master configuration, slave connection status EE09.3 No sync signal Check distributed clock configuration, master sync signal 5.3 Fault Black Box Function
The SV660N features a fault black box function that records key operational data at the time of fault occurrence via H0b group monitoring parameters. The standard type records 10 fault groups; the NS upgraded version records 20. Fault record contents include:
- H0b.34: Selected fault code
- H0b.35: Selected fault timestamp (total servo run time, in seconds)
- H0b.37: Motor speed at fault (rpm)
- H0b.38: Motor U-phase current at fault (A)
- H0b.39: Motor V-phase current at fault (A)
- H0b.40: DC bus voltage at fault (V)
- H0b.41: Input terminal status at fault
- H0b.43: Output terminal status at fault
The NS upgraded version adds black box channels including fault sub-code, operating mode (6060h+6061h), EtherCAT port error statistics (H0E.25/H0E.27/H0E.28), and EtherCAT state machine status (H0E.33). It also supports reading all black box channels and continuous trigger mode, significantly enhancing fault diagnostic capability.
5.4 Panel NRD Status Display
When the servo is in a not-ready state, the panel displays “nr”. The standard type displays only “nr”, while the NS upgraded version differentiates four sub-states: nr.1, nr.2, nr.3, and nr.4, each representing a different not-ready cause for rapid problem identification.
5.5 Fault Reset Methods
After troubleshooting, faults can be reset via the following methods:
- Non-bus mode: Reset via DI terminal ALM-RST (FunIN.2) signal
- Bus mode: Reset via the fault reset bit in control word 6040h
- Panel operation: Press SET key to reset
- STO-related faults (E150.x): Must follow the STO fault reset procedure specified in the manual
6. Maintenance and Upkeep
6.1 Daily Inspection Items
- Check for abnormal sounds, odors, or excessive heat during drive operation
- Verify panel display is normal with no fault or warning messages
- Check motor operation for smoothness and absence of abnormal vibration
- Verify cooling fan operates normally (for air-cooled models)
- Check CHARGE indicator status; confirm bus capacitor discharge after power-off
6.2 Daily Cleaning Items
- Keep the drive surface clean to prevent dust accumulation affecting heat dissipation
- Clean cooling ducts and ventilation openings to ensure airflow
- For -FH high-protection models, regularly inspect protective seal integrity
6.3 Periodic Maintenance Items
- Check terminal screw tightness; re-tighten to manual-specified torque values
- Inspect cables for damage or aging; verify reliable shield grounding
- Check EtherCAT communication cable connections for secure RJ45 engagement
- Check absolute encoder battery voltage; replace promptly (for multi-turn absolute encoders)
- Inspect braking resistor for overheating discoloration or damage
- Verify installation status of EMC filters, magnetic cores, and other interference suppression devices
6.4 Common Problems and Solutions
The manual appendix provides an extensive troubleshooting guide. Typical issues include:
- Panel not displaying: Check control power input, power cable connections, and internal fuse
- Smoke or component failure at power-on: Immediately disconnect power; check for wiring errors or short circuits; do not re-apply power
- Motor does not rotate: Check enable signal, control mode, parameter settings, and motor wiring phase sequence
- Panel shows nr.x at power-on: Standard type displays “nr” for not-ready; NS version displays nr.1 through nr.4 for different causes
- Cannot connect to debugging software: Check CN5 RS232 connection, software version, and drive communication address
- Parameters cannot be modified: Check if servo is enabled (some parameters require disabled state); verify parameter protection settings
- Circuit breaker trips at power-on / RCD trips: Check wiring insulation, EMC filter installation; consider adding magnetic cores
- Brake cannot release: Check brake wiring, DO function assignment (FunOUT.9 BK), and brake power supply
- Panel displays 88888: Internal drive abnormality; power cycle; if persistent, contact manufacturer
- EtherCAT communication interference: Check communication cable shield grounding, route away from power cables, add magnetic clamps
7. Conclusion
The SV660N series, as Inovance Technology’s flagship EtherCAT bus servo product, demonstrates unique technical advantages in multi-axis coordinated control, high-precision synchronous motion, and semiconductor manufacturing applications. Compared with the SV660A and SV660P, its core differences include: a complete transition from pulse/analog control to EtherCAT bus control, supporting cyclic synchronous modes (CSP/CSV/CST), distributed clock synchronization, and ring topology redundancy — all bus-exclusive capabilities. The product differentiation strategy between the standard and NS upgraded versions provides flexible choices for applications with varying reliability requirements. Features such as multi-axis recipe management, enhanced black box diagnostics, and EtherCAT forced DO output further extend its application depth in complex automated production lines.
The key to effectively using the SV660N lies in: understanding the EtherCAT communication architecture and CiA 402 state machine model, mastering the configuration methods for H0E group communication parameters, familiarizing oneself with the applicable scenarios of the seven control modes, leveraging ETune/STune auto-tuning and vibration suppression functions, and building a systematic troubleshooting approach based on the fault black box. Engineers are advised to use the Inovance debugging software (connected via CN5 RS232) for parameter configuration and status monitoring in practical applications, while referring to the SV660N Series Servo Communication Manual (Document Code: 19011395) for in-depth EtherCAT communication configuration details.
This guide is based on the SV660N User Manual version B06. As the product continues to evolve, it is recommended to periodically obtain the latest manual version through the Inovance Technology official website or the Inovance Pocket App to ensure technical information accuracy.