Troubleshooting and Maintenance of KUKA KR C4 Compact Control Cabinet

Daily maintenance and periodic inspections

The maintenance work of KR C4 compact should be carried out on a periodic basis. Check the output of the relays used by CCU_SR every 6 months to ensure they are functioning properly. The specific methods include: pressing the local emergency stop button and checking the local emergency stop output; Set the mode to automatic or automatic external, turn on operator safety, and check the operator safety confirmation output; Release the enable switch in T1 or T2 mode and check the peripheral connection output. If there is no error message, it indicates that the relay output is normal.

Emergency stop equipment, enable switches, and external enable devices should undergo functional testing every 12 months. When testing the enable switch, move the robotic arm in test mode while fully pressing and holding a certain enable switch for 3 seconds. The robotic arm should stop and no enable device error should be displayed. If a certain enable switch fails the test, the smartPAD needs to be replaced and retested. The protective grille and fan should be cleaned every 12 months according to the installation conditions and pollution level. Before cleaning, it is necessary to turn off the power, hang the tag, and wait for at least 5 minutes for the intermediate circuit to discharge. KPP_SR, KSP_SR, motor connections, and intermediate circuit cables in the intermediate circuit may still carry a voltage of 50 V to 300 V within 5 minutes after power failure, and the waiting time must be strictly observed. Do not use compressed air, spray water, or allow cleaning agents to enter electrical components during cleaning.

The motherboard battery, control box fan, and drive box fan need to be replaced every 5 years. The battery replacement cycle also depends on the storage temperature: when the storage temperature is not higher than+20 ° C, it should be charged every 9 months; +Charge every 6 months from 20 ° C to+30 ° C; +Charge every 3 months from 30 ° C to+40 ° C. If the battery is depleted for a long time, it may be completely damaged. After maintenance is completed, a visual inspection should be conducted to confirm that fuses, contacts, plugs, and boards are securely installed, cables are undamaged, PE equipotential connections are reliable, and system components are not worn or damaged.

LED diagnosis and common fault handling

The LED display on CCU_SR is the first-hand information for fault diagnosis. PHY4 and SW-P0 are green, constantly on or flashing indicates normal, and off indicates a fault. Usually, the CCU_SR module needs to be replaced. The RUNSION EtherCAT Safety node LED is green, constantly on indicates normal operation, off indicates initialization, 2.5 Hz flashing indicates Pre Op, single signal indicates Safe Op, and 10 Hz flashing indicates firmware update boot. L/A KSB and L/A KCB are green/orange, with green constantly on indicating normal physical connection, orange indicating 1 Gbit, flashing indicating data traffic, and off indicating unplugged network cable or connection failure. PWR/3.3V, PWR/2.5V, and PWR/1.2V are green power indicators. Before turning off, check the F17-3 and F308 fuses first; If powered externally through X308, it is also necessary to check the external 24V voltage. Check F17-3 when PWRS/3.3V is turned off; If the PWR/3.3V is on and the PWRS/3.3V is off, it may be necessary to replace the CCU_SR.

STAS2 and STAS1 are orange security node indicator lights. Extinguish indicates no power supply, check F17-3; If PWR/3.3V is on, consider replacing CCU_SR. A 1 Hz flicker indicates normal operation, while a 10 Hz flicker indicates the guidance phase. If the fault code flashes, check the X309, X310, and X312 cables and try disconnecting them before restarting the controller. FSoE green indicates the status of EtherCAT security protocol, off indicates inactive, constant light indicates running, and flashing indicates internal fault code. 27V, PS1, and PS2 are green power indicators, corresponding to main power, short-term battery backup, and medium battery backup, respectively. When the 27V is turned off, check the X1 incoming line, rated at 27.1 V; when the PS1 is turned off, check whether the X1 incoming line or drive bus is in BusPowerOff state; Check if X1 or controller is in Sleep state when PS2 is turned off.

In terms of fuses, F301 is powered by a 24V battery free backup option, 10 A; F15 is a power unit fan, 2 A; F308 is an external power supply, 7.5 A. If the fuse is blown, it must be replaced with a fuse of the same specification after troubleshooting. Common faults also include: no display after power on, checking equipment switches, power connections, and fuses; After the safety door is opened, it cannot automatically recover. Check the operator's safety confirmation button and safety configuration; The enable switch is invalid. Check if the external enable terminal of X11 is short circuited or if there is a smartPAD enable switch; Communication interruption, check X21 data cable, X66 Ethernet security interface, and grounding.

Key component replacement process

When replacing internal components of KR C4 compact, the basic procedures of power-off, hanging, waiting for 5 minutes, and ESD protection must be followed. The control box cover is fixed with screws, and when opened, it can access the motherboard, battery RAM、 Hard drive CCU_SR、 Network card, power supply, fan, etc. The drive box and control box are fixed by connecting plates and handle brackets. When disassembling, it is necessary to first remove the screws of the rear connecting plate and the upper screws of the left and right handle brackets, and then lift the control box and flip it backwards.