FANUC Series 16i/18i/21i MODEL B Series CNC System Hardware Connection

FANUC Series 16i/18i/21i MODEL B Series CNC System Hardware Connection Manual (B-63523EN/03), fully covering system composition, overall wiring diagram, installation environment, power wiring, peripheral connections, spindle/servo interfaces I/O Link、 Full hardware wiring specifications for emergency stop, network, PC functional units, etc., specifying 24VDC power supply, FSSB fiber optic servo, serial spindle, etc RS‑232C、 The definition and wiring rules of core interfaces such as Ethernet and emergency stop safety circuits, providing terminal definitions, cable specifications, anti-interference, heat dissipation, and mandatory grounding requirements, are the authoritative basis for electrical installation, wiring, debugging, and acceptance of this series of CNC systems.

System composition and overall wiring

1. Host structure

Divided into two structures: LCD integrated and split type

Standard configuration: LCD unit, MDI keyboard, soft keys, memory card interface

Expansion: option slot, mini slot, network/HSSB/remote buffer card

2. Overview of complete machine wiring

Servo: FSSB fiber COP10A/B cascaded amplifier

Spindle: JA41 serial or JA40 analog

I/O: I/O Link (JD44A) connects distributed I/O

Peripherals: RS-232C, Ethernet, Handwheel MDI

Safety: Emergency stop circuit, limit, overload protection

Installation and Environmental Standards

1. Environmental parameters

Parameter indicators

Working temperature 0~55 ℃

Humidity 10~90% RH (no condensation)

Altitude ≤ 2000m

Vibration working ≤ 0.5G, non working ≤ 1G

Protection must be installed in an IP54 sealed cabinet

2. Heat dissipation and spacing

The temperature rise inside the cabinet is ≤ 13 ℃, and the operating panel is ≤ 10 ℃

The distance between the upper and lower heat dissipation of the host is ≥ 50mm

The fan has a wind speed of 0.5m/s along the surface of the equipment

3. Grounding and anti-interference

Protective grounding: Class D ≤ 100 Ω, wire diameter ≥ 2mm ²

Signal grounding (SG): Independent terminal single point grounding

Cable grouping:

Group A: Strong electric/power line

Group B: I/O signal line

Group C: Servo/Spindle/Communication Shielded Wire

Inter group spacing ≥ 10cm, shielding layer 360 ° ring grounding

Power and battery wiring

1. Power supply requirements

Main power supply: 24VDC ± 10% (21.6-26.4V)

Instantaneous power outage maintenance: -50%/20ms, -100%/10ms

Current: Integrated host 1.7~2.0A, split type 1.8A

2. Power on/off sequence

Power on: Whole machine AC → Servo power → CNC 24V

Power off: CNC 24V → servo power supply → whole machine AC

3. Battery specifications

Application voltage replacement requirements

Parameter backup 3V, replace within 30 minutes after power failure

Absolute encoder 6V power on replacement to prevent coordinate loss

Replace PC functional unit 3V within 5 minutes

Core interface wiring

1. Servo interface (FSSB)

Interface: COP10A/COP10B fiber optic interface

Number of axes: 16i maximum 8 axes, 18i maximum 6 axes, 21i maximum 4 axes

Length: Unit spacing ≤ 100m, total length ≤ 500m

External: Separate detector interface unit, grating ruler

2. Spindle interface

Serial spindle: JA41, supports 1-4 axes

Simulated spindle: JA40, 0~10V command

Position encoder: A/B/Z differential signal

3. Peripheral interface

RS‑232C：JD36A/B， Baud rate 50~9600bps, line length ≤ 50m

Ethernet: CD38A, 100BASE-TX, line length ≤ 100m

High Speed Skip (HDI): JA40, up to 8 points

MDI/LCD：CA55、JD45、COP20A/B

4. I/O Link

Interface: JD44A

Support: distributed I/O, operation panel I/O, handwheel, beta amplifier

Wiring: shielded cable, strong current separation

Safety circuit (emergency stop)

Emergency stop is a mandatory external hard wired system and cannot be solely reliant on PMC

Circuit series connection: emergency stop switch, limit switch, servo emergency shutdown

Fault directly cuts off servo enable and spindle enable

PC functional unit (optional)

Architecture: Industrial PC+CNC, Windows system

Power supply: 24VDC, maximum 7A

Interfaces: HSSB, USB, serial port, parallel port PCMCIA、PCI

Requirement: The device must be shut down normally, and it is prohibited to turn off the HDD when the power is turned off

Appendix and Specifications

Provide: external dimensions, connector definition, recommended cables, fiber optic specifications

Key cables:

FSSB fiber: A66L-6001 series

MDI/RS232: A66L-0001 0284 series

Ethernet: Category 5 Shielded STP

Key issues

Question: What are the maximum number of axes, wiring length, and rules that must be followed for the servo FSSB bus of the 16i/18i/21i system? 

Answer: 16i up to 8 axes, 18i up to 6 axes, 21i up to 4 axes; Fiber between units ≤ 100m, total length ≤ 500m; FANUC specified fiber must be used, amplifier sequence fixed, and separation detector unit must be at the end.

Question: What is the allowable range of 24VDC power supply for this system, the instantaneous power-off holding index, and the power on sequence? Answer: Voltage range 21.6-26.4V (± 10%); Maintain the ability of * * -50%/20ms, -100%/10ms * *; Power on sequence: AC power supply for the whole machine → servo control power supply → CNC 24VDC.

Question: What are the mandatory standards for cable grouping, grounding requirements, and shielding treatment in machine tool wiring? 

Answer: The cables are laid independently in groups A/B/C, with a spacing of ≥ 10cm; protective grounding * * ≤ 100 Ω * *, wire diameter ≥ 2mm ²; All shields must have a 360 ° ring grounding plate, and single point welding grounding is prohibited.