Electrical Installation & Design
Source: 02.ES750N_电气安装.html (the “Electrical Installation” chapter of the ES750N series servo-drive manual)
Scope
This page covers the installation and wiring essentials of the ES750N dual-axis servo drive in injection-molding machine electro-hydraulic servo systems, targeting electrical designers, cabinet assemblers, field commissioners, and after-sales maintenance personnel. The ES750N covers 11kW–55kW (three chassis types T1/T2/T3) and can drive two PMSMs simultaneously (U1V1W1 + U2V2W2).
The following content is extracted from text after PDF-to-HTML conversion. For terminal numbers, parameter numbers, ratings, and safety requirements, always refer to the original manufacturer manual.
Pre-wiring checks
Do not wire the drive while power is applied. Keep all breakers OFF; otherwise there is a risk of electric shock.
- After disconnecting input and output power, wait 10 minutes, measure the bus voltage until it is below 36 V and the power indicator is fully off, then start work.
- The operator is responsible for installing and connecting the motor, cabinet equipment, and other components in accordance with the country’s recognized technical regulations and any applicable regional rules. Pay particular attention to cable sizing, fuses, grounding, disconnection, isolation, and overcurrent protection.
- If a branch fuse trips, fault current may have been interrupted. To reduce the risk of fire and electric shock, inspect conductive parts and components and replace damaged ones. After a fuse trips, identify and eliminate the cause.
Main-circuit terminal description
The ES750N is available in three frame sizes by power rating: T1 (11kW–22kW), T2 (30kW–37kW), T3 (45kW–55kW).
| Terminal | Name | Function |
|---|---|---|
| R, S, T | Three-phase power input | AC three-phase input connection |
| (+), (−) | DC bus positive/negative | Common DC bus input; connection for an external braking unit |
| (+), BR | Braking-resistor terminals | Braking resistor for applicable models |
| U1, V1, W1 | Axis 1 output | Connect axis-1 three-phase motor |
| U2, V2, W2 | Axis 2 output | Connect axis-2 three-phase motor |
| PE | Ground terminal | Protective earth |
The ES750N is a dual-axis drive with two independent output terminals (U1V1W1 and U2V2W2). Verify that each motor’s connection terminals match its encoder connection to avoid swapping axes.
Main-circuit cable selection
Requirements
- PVC insulation, pure-copper conductors.
- 40℃ ambient, 70℃ cable surface temperature. (If ambient exceeds 40℃, contact the manufacturer.)
- Cable installation per IEC 60204-1.
- Use shielded cable to meet EMC requirements. Shield braid density must exceed 90%.
Recommended main-circuit cable sizes (national standard)
| Size | Power (kW) | Rated input current (A) | RST/U1V1W1/U2V2W2 cable (mm²) | RST/U1V1W1/U2V2W2 lug | Ground cable (mm²) | Ground lug | Terminal width (mm) | Screw | Tightening torque (N·m) |
|---|---|---|---|---|---|---|---|---|---|
| T1 | 11 | 34 | 3 × 6 | GTNR6-5 | 6 | GTNR6-5 | 10 | M5 | 2.8 |
| T1 | 15 | 41 | 3 × 10 | GTNR10-5 | 10 | GTNR10-5 | 12.4 | M5 | 2.8 |
| T1 | 18.5 | 51 | 3 × 10 | GTNR10-5 | 10 | GTNR10-5 | 12.4 | M5 | 2.8 |
| T1 | 22 | 61 | 3 × 16 | GTNR16-5 | 16 | GTNR16-5 | 12.4 | M5 | 2.8 |
| T2 | 30 | 58 | 3 × 16 | GTNR16-6 | 16 | GTNR16-6 | 12.4 | M6 | 4.8 |
| T2 | 37 | 71 | 3 × 25 | GTNR25-6 | 16 | GTNR16-6 | 14 | M6 | 4.8 |
| T3 | 45 | 94 | 3 × 35 | GTNR35-8 | 25 | GTNR25-8 | 16.5 | M8 | 13 |
| T3 | 55 | 110 | 3 × 50 | GTNR50-8 | 35 | GTNR35-8 | 18 | M8 | 13 |
Recommended lugs are Suzhou Yuanli GTNR series. “3 × 10” means one 3-core 10 mm² cable.
Recommended main-circuit cable sizes (UL)
| Size | Power (kW) | Rated input current (A) | RST/U1V1W1/U2V2W2 cable (AWG) | RST/U1V1W1/U2V2W2 lug | Ground cable (AWG) | Ground lug | Terminal width (mm) | Screw | Tightening torque (N·m) |
|---|---|---|---|---|---|---|---|---|---|
| T1 | 11 | 34 | 8 | TLK10-5 | 8 | TLK10-5 | 12 | M5 | 2.8 |
| T1 | 15 | 41 | 6 | TLK16-5 | 6 | TLK16-5 | 12 | M5 | 2.8 |
| T1 | 18.5 | 51 | 6 | TLK16-5 | 6 | TLK16-5 | 12 | M5 | 2.8 |
| T1 | 22 | 61 | 4 | TLK25-5 | 4 | TLK25-5 | 14 | M5 | 2.8 |
| T2 | 30 | 58 | 4 | TLK25-6 | 4 | TLK25-6 | 14 | M6 | 4.8 |
| T2 | 37 | 71 | 2 | TLK35-6 | 4 | TLK25-6 | 14 | M6 | 4.8 |
| T3 | 45 | 94 | 1 | TLK50-8 | 2 | TLK35-8 | 16.5 | M8 | 13 |
| T3 | 55 | 110 | 1/0 | TLK70-8 | 2 | TLK35-8 | 18 | M8 | 13 |
Recommended lugs are KST’s TLK series. AWG notes: “4” is 4 AWG, “2” is 2 AWG, “1” is 1 AWG, “1/0” is 0 AWG.
Main-circuit wiring requirements
- External main-circuit wiring specifications and installation must comply with local regulations and applicable IEC standards.
- No phase-sequence requirement on the drive input R, S, T.
- To protect the main circuit, isolate it from any surfaces it may touch.
- The control circuit is a safety extra-low-voltage circuit; keep it reinforced-insulated from other circuits.
- Do not solder stranded conductors.
- Terminal tightening torques may differ; tighten each screw to the specified torque.
- Terminals BR, (−), and (+) are for optional equipment. Do not connect them to AC power.
DC bus wiring
Right after power-off, residual voltage remains on the DC-bus (+), (−) terminals. Wait until the power indicator is off and at least 10 minutes have passed before wiring. Otherwise there is a risk of electric shock.
- Keep braking-unit wiring under 10 m. Use twisted-pair or closely paralleled double wires.
- Do not connect the braking resistor directly to the DC bus; doing so may damage the drive or cause a fire.
- Select the braking resistor per recommended values, and keep wiring under 5 m.
- Do not allow combustibles near the braking resistor.
Main-circuit routing
Drive power-input and motor cables produce strong electromagnetic interference. Keep main-circuit cables at least 30 cm away from signal cables. Common main-circuit cables are input RST, output U1V1W1/U2V2W2, DC bus, and braking cables; signal cables are I/O, communication, and encoder cables.
Cable ducts must be well connected and well grounded. Aluminum ducts maintain equipotential. The filter, drive, and motor should all be well bonded to the system.
Control-circuit wiring
Control-circuit terminals
The ES750N’s control-circuit interfaces include analog inputs, digital inputs/outputs, relay outputs, communication, and encoder interfaces.
Analog inputs (AI1–AI4)
| Terminal | Name | Description |
|---|---|---|
| AI1 | Analog input 1 | Pressure-command input, DC 0V–10V |
| AI2 | Analog input 2 | Flow-command input, DC 0V–10V |
| AI3 | Analog input 3 | Pressure-feedback input, DC 0V–10V |
| AI4 | Analog input 4 | Spare analog input |
Digital inputs (DI1–DI7)
| Terminal | Name | Description |
|---|---|---|
| DI1–DI7 | Digital inputs 1–7 | Opto-isolated; function assigned by parameter (e.g. servo enable, fault reset) |
| COM | Common | DI common |
Digital outputs and relay
| Terminal | Name | Description |
|---|---|---|
| DO1, DO2 | Digital outputs 1, 2 | Opto-isolated open-collector |
| T/A, T/B, T/C | Relay output | Dry-contact relay output |
STO terminals
The ES750N provides independent STO (Safe Torque Off) interfaces for each axis:
| Interface | Description |
|---|---|
| CN7 | Axis-1 STO |
| CN8 | Axis-2 STO |
When STO is not used, short STO1, STO2, and 24VD. Remove the jumper to use STO. STO meets SIL3.
Encoder connection
During field installation, route signal cables (e.g. encoder cables) in separate ducts from power cables. Do not bundle encoder cables with power cables; doing so is a frequent cause of encoder interference. The motor casing must be connected to the drive PE terminal, and the motor-side ground must be well bonded.
The ES750N dual-axis drive has two independent encoder interfaces:
| Interface | Description |
|---|---|
| CN11 | Axis-1 encoder interface (resolver / 23-bit encoder) |
| CN10 | Axis-2 encoder interface (resolver / 23-bit encoder) |
Resolver (R1 drive) wiring
The resolver connects to the drive through a PG card. See the original manufacturer manual for the pinout of the PG card.
23-bit encoder (C1 drive) wiring
The 23-bit encoder connects to the drive through a PG card and includes PT1000 motor-temperature sensing. If you build your own encoder cable, use twisted-pair shielded cable with conductors no smaller than 26 AWG. Ground the shield at both ends—to the drive PE and the motor casing.
The C1 drive paired with the A3 series high-performance encoder runs tuning-free. The R1 drive (resolver) requires motor-parameter identification.
Communication connection
EtherCAT
| Interface | Description |
|---|---|
| CN9 | EtherCAT interface |
EtherCAT supports 100 Mbps standard operation with COE and EOE application layers. Supported topologies include bus, star, and tree.
CAN
| Interface | Description |
|---|---|
| CN4 | CAN interface |
Use three-core shielded cable for the CAN bus. Connect CANH, CANL, and CGND. CANH/CANL are twisted; the third conductor is the CAN reference ground CGND. Bond the shield to equipment ground. Install a 120 Ω termination resistor at each end.
In cross-cabinet installations, tie all CAN shields to CGND. Do not tie the CAN shield to PE.
Grounding
Ground the drive reliably. The product leakage current exceeds 3.5 mA, so per IEC/EN 61800-5-1 use a protective earth conductor of at least 10 mm² copper.
- Use yellow-green copper cable for the protective earth conductor; do not insert a breaker or similar switching device in series.
- The ground terminal must be reliably grounded; otherwise equipment may malfunction or be damaged.
- Do not combine the ground terminal with the neutral wire N.
- Install on a conductive metal mounting surface for good bonding.
- Tighten ground screws to the recommended torque.
Post-wiring checks
| Item | Check |
|---|---|
| 1 | Drive matches the ordered model. |
| 2 | Peripheral equipment (braking resistor, braking unit, AC reactor, filter, breaker, etc.) matches the design. |
| 3 | Installation method and location meet requirements. |
| 4 | Drive input voltage is within 323 V–528 V. |
| 5 | Motor rated voltage matches the drive output rating. |
| 6 | Input power is connected to R, S, T. |
| 7 | Axis-1 motor connects to U1, V1, W1; axis-2 motor connects to U2, V2, W2. |
| 8 | Main-circuit cable size meets requirements. |
| 9 | Grounding is correct. |
| 10 | Drive output and control signal terminals are firmly fastened. |
| 11 | If a braking resistor and unit are used, wiring is correct and resistance is suitable. |
| 12 | Control-circuit signal cables are shielded twisted pair. |
| 13 | Control-circuit cables are routed separately from main-circuit power cables. |
| 14 | Encoder wiring is firm; axis-1 encoder on CN11, axis-2 encoder on CN10. |