KUKA KR C4 compact assembly and debugging

KUKA KR C4 compact assembly and debugging

KUKA KR C4 compact is a compact controller launched by KUKA for small robot applications. It adopts a 19 inch chassis structure, can control up to 6 axes, weighs about 33 kg, has a protection level of IP20, and an average noise of about 54 dB (A). It consists of two main parts: a control box and a drive box, with internal integrated control PC, CCU_SR, low-voltage power supply, battery, main filter, fan, etc KPP_SR、KSP_SR、 Braking resistor and interface panel. For on-site engineers, mastering the assembly, wiring, safety configuration, and start-up debugging processes is the foundation for ensuring the safe and stable operation of robot systems.

System composition and core modules

The industrial robot system of KR C4 compact includes a robotic arm, robot controller, smartPAD teaching pendant, connecting cables, software, and options. The robot controller is used to control KUKA small robots and consists of a control PC, power unit, safety logic, smartPAD control panel, and connection panel. The control box contains a fan, hard drive, low-voltage power supply, EDS storage card CCU_SR、 Cover interface, device switch, interface, options, motherboard, and battery. The drive box contains X20 motor interface, braking resistor KPP_SR、 Main filter, KSP_SR, and fan.

The control PC is responsible for graphic interface, program creation and maintenance, sequence control, path planning, drive circuit control, monitoring, safety equipment, and external communication. CCU_SR stands for Small Robot Cabinet Control Unit, consisting of CIB_SR and PMB_SR. It serves as the central power distribution and communication interface, responsible for safety input/output, contactor activation, 4 floating outputs, 9 safety inputs, teaching pendant insertion recognition, mastering testing, 6 rapid measurement inputs, power fan monitoring, and temperature detection inside the control box. If the main power supply fails, the battery will continue to supply power to the control components until the position data is saved and the controlled shutdown is completed. The low-voltage power supply supplies power to the control cabinet components, and the green LED indicates the working status. The main filter suppresses interference voltage on the power line. The drive box generates intermediate circuit voltage, controls the motor and brake, and checks the intermediate circuit voltage in braking mode.

Interface layout and motherboard selection

The standard configuration of the KR C4 compact's connection panel includes device connection cables, motor cables, data cables, smartPAD cables, and peripheral cable interfaces. The specific interfaces include X11 security interface, X19 smartPAD connection, X65 expansion interface, X69 service interface, X21 robotic arm interface, X66 Ethernet security interface, K1 power connection, X20 motor interface, and control PC interface. X11 and X66 cannot be connected and used simultaneously, only one can be selected.

The control PC can be equipped with D3076-K, D3236-K, or D3445-K motherboards. D3076-K provides 4 fieldbus slots, 2 USB 2.0, DVI-I, 4 USB 2.0, and LAN Onboard interfaces. D3236-K provides 2 fieldbus slots, 2 USB 3.0, DVI-I, 4 USB 2.0, and LAN Onboard interfaces. D3445-K provides 2 fieldbus slots, 2 USB 3.0, DVI-D, Display Port, 4 USB 2.0, and LAN Onboard interfaces. VGA can be achieved through a DP or DVI to VGA adapter, but external displays are only available when not connected to a smartPAD or virtual remote teaching pendant. All contactors, relays, and valve coils connected by users must be equipped with suitable suppression diodes, RC components, and VCR resistors are not applicable.

Cooling and installation conditions

The components of the control box and drive box are cooled by two fans using ambient air. Air enters from both sides and exits from the back. Do not install filter cotton upstream of the ventilation duct, otherwise it will cause temperature rise and shorten equipment life. The control cabinet can be installed in a 19 inch rack or used as a standalone device. The rack depth should be at least 700 mm. The controller is designed for horizontal installation or can be installed vertically. A 70 mm cooling air gap must always be maintained on both sides to prevent deformation of the casing. When installed vertically, the fan opening and ventilation duct must not face upwards.

The installation environment must avoid conductive dust and condensation. If there is conductive dust or condensation, it may cause the internal electrical connections to lose control. Environments with pollution levels of 3 or 4 require the installation of protective enclosures with a minimum protection level of IP54, depending on the environmental conditions. The operating environment temperature ranges from 5 ° C to 45 ° C, and the storage and transportation temperature ranges from -25 ° C to 40 ° C. Without a battery, the storage and transportation temperature can be extended to -25 ° C to 70 ° C. No derating is required below an altitude of 1000 meters, and a derating of 5%/1000 meters is required below 3000 meters. Transport vibration 0.37 g, continuous operation 0.1 g, frequency 4 to 120 Hz; impact transport 10 g, operation 2.5 g, half sine 11 ms. If mechanical stress is high, anti vibration components need to be installed. Charge the battery every 9 months when the storage temperature is not higher than+20 ° C, every 6 months when the temperature is between+20 ° C and+30 ° C, and every 3 months when the temperature is between+30 ° C and+40 ° C to prevent damage from deep discharge.

Security features and X11 interface

The safety features of KR C4 compact comply with EN ISO 13849-1 Category 3 and Performance Level d. Emergency stop devices and enabling devices must be tested at least once every 12 months. The safety functions include operation mode selection, operator safety, emergency stop device, enabling device, external safety operation stop, external safety stop 1, external safety stop 2, and T1 speed monitoring. In T1 mode, the default speed limit for the rotating axis is 30 °/s, the linear axis is 250 mm/s, and the Cartesian speed is 250 mm/s. The definition of safe stop includes STOP 0, STOP 1, and STOP 2. STOP 0: Immediately disconnect the drive and apply the brake; STOP 1 brakes in path holding mode and disconnects the drive after stopping; STOP 2 maintains drive and brake, braking in a path keeping manner.

X11 security interface is internally connected to CCU. The default pin assignments include: test outputs A and B, external emergency stop channels A and B, operator safety channels A and B, confirm operator safety, safety operation stop, safety stop 2, external enable 1 and 2, local emergency stop output, confirm output, and Peri enabled output. External enable 1 must be pressed when moving at T1 or T2, input closed; External enable 2 must not be in the panic position, input closed. If external enable 1 is not connected, short circuit 20/21 of channel A and 30/31 of channel B; Not connected to external enable 2, short circuit 22/23 of channel A and 32/33 of channel B. If smartPAD is connected, its enable switch performs AND logic with external enable.

During dynamic testing, the test output is alternately turned off, with a turn off pulse length t1 of 625 μ s and a range of 125 μ s to 2.375 ms. The time t2 between two turn off pulses on the same channel is 106 ms, and the offset t3 between two turn off pulses on the same channel is 53 ms. The input channel SIN_X_A must be powered by TA_S, and SIN_X_B must be powered by TA-B. The safety output is a dual channel floating relay output, and the power supply must come from a safety isolated PELV power supply. The wiring example can achieve SIL2 and Cat. 3. When wiring, input signals and test signals, output signals and test signals must be separated to prevent cross connections.

Ethernet Security Interface and Expansion Interface

The X66 Ethernet safety interface supports PROFIsafe or CIP Safety and is used to connect upper level safety PLCs. The input byte 0 contains reserved bits, external emergency stop, operator safety, confirmation, safety stop 1, and safety stop 2. Output byte 0 contains local emergency stop, drive enable, motion enable, enable signal, Peri enabled, AUT, T1 and T2 modes. It is recommended to preset the input to 1 to prevent unexpected activation of new security features after software updates, which may cause downtime. SafeOperation can be used through an Ethernet secure interface, with input bytes including mastering testing, slowing down, stopping secure operations, monitoring space, and tool selection; The output bytes include SO, RR, JF, VRED, SBH, and MR. X66 is an RJ45 interface, recommended for CAT 5e or above Ethernet cables, with a maximum wire diameter of AWG22. X65 is an EtherCAT interface used to connect external EtherCAT slaves and requires WorkVisual configuration. X69 is a KUKA service interface used to connect laptops for diagnosis, WorkVisual configuration, and updates. It is recommended to use CAT 5 or higher Ethernet cables.

Transportation, installation, and start-up debugging

Before transportation, the control cabinet casing must be closed, cables must not be connected, and a horizontal position must be maintained. Forklifts or pallet trucks can be used, and the control cabinet should be placed on the pallet. Avoid vibration and impact to prevent poor contact of PC card insertion. During installation, first check the control cabinet for any transportation damage, confirm that the fuses, contactors, and boards are securely installed, tighten all screws and clamp connections. The installation position should be easy to maintain, with cooling gaps left on both sides.

Connect PE equipotential: Use a 4 mm ² cable to connect the robotic arm and robot controller, and then connect the central PE row of the power supply cabinet to the PE connection point of the controller. Connect motor cable X20 to the drive box, data cable X21 to the control box, smartPAD to X19, and power supply to K1. Restore battery discharge protection connector X305 to CCU. Configure X11 security interface to ensure compliance with system security concepts. Before powering on, check the safety equipment to ensure that all safety functions are complete and effective. Start the control cabinet and check the machine data mastering、 Tool calibration, load data, and software limit switches. Functional testing includes local emergency stop, external emergency stop, enabling devices, operator safety, and other safety inputs and outputs. After modifying the security configuration, it is necessary to recheck.

Maintenance and common precautions

Maintenance and repair must be carried out by cutting off power, hanging tags, and waiting for the intermediate circuit to discharge. After the control cabinet is powered off, there may still be a voltage of 50 V to 780 V within 5 minutes, and it must be confirmed that there is no power. Comply with ESD regulations to prevent static electricity from damaging electronic components. The control cabinet must be connected to a power system with a grounded neutral point. RCCB recommendation: Use 300 mA for controllers before WK35/2017, and 30 mA for each controller after WK36/2017, with universal current sensitivity and selectivity. The smartPAD cable can be extended up to two times, with a total length of no more than 50 meters. The cable length difference between each channel of the RDC box should not exceed 10 meters. The battery should be charged regularly to avoid deep discharge. Do not use compressed air, spray water, or allow cleaning agents to enter electrical components during cleaning. Replacement parts must use original factory spare parts. The safe lifespan is 20 years, and the PFH value of KR C4 compact is less than 1 x 10 ^ -7.