KUKA KR C5 micro debugging and troubleshooting

KUKA KR C5 micro debugging and troubleshooting

The KUKA KR C5 micro is a controller platform designed for small robots, compact workstations, and limited installation spaces. It is equipped with the KUKA iiQKA.OS operating system, supports up to 6 servo axes, weighs approximately 9.8 kg, has an IP20 protection level, and produces noise levels below 54 dB (A). Unlike large cabinet controllers, the KR C5 micro integrates the control box, drive box, safety logic, interface board, and cooling system into a flat or vertical housing, which can be placed independently, stacked, wall mounted, 19 inch rack mounted, or used as a panel mounted variant. For on-site engineers, the most important concerns are how to identify the control box and drive box, how to configure safety chains, how to wire, how to power on, how to replace modules, and where to start checking after an alarm. This article revolves around these practical issues.

System architecture: division of labor between control box and drive box

The KR C5 micro consists of a control unit and a power unit. The control unit, also known as the control box, contains a mini CSP, button battery, SSD hard drive, system board, IFBstd interface board, internal SSD storage, and fan. The system board is responsible for controlling the computer, including graphical interfaces, program creation and modification, path planning, sequence control, drive loop control, monitoring, safety equipment communication, and external device communication. The IFBstd interface board provides non secure digital I/O and is connected to the system board through a ribbon cable; The system board is connected to KSP through ICT plug and is powered by KSP. Mini CSP is a status display component that provides feedback on operating mode, operating status, errors, and sleep status through LED1 to LED4 and a soft power button.

The drive box, also known as the drive box, includes a fan, main filter, braking resistor, radiator, and KSP-300 drive controller. KSP-300 consists of FCU-300 and SCU-6-1S, responsible for generating intermediate circuit voltage and system voltage, controlling motors, controlling brakes, and checking intermediate circuit voltage in braking mode. It should be noted that the power unit of the drive box cannot be opened arbitrarily, otherwise it may cause serious injury or property damage.

The rated power supply of KR C5 micro is AC 1 × 200 V to 240 V, single-phase or two-phase, with an allowable deviation of ± 10%. The rated connection power is 1.30 kVA, the system impedance is not greater than 300 m Ω, the ground leakage current is not greater than 10 mA, the main power side fuse is 1 × 16 A slow melting C-type, the frequency is 50 to 60 Hz, and the maximum thermal output is 250 W. The equipment side fuse is 2 × 10 A slow melting C-type. The operating temperature is -5 ℃ to+45 ℃, and the storage and transportation temperature is -20 ℃ to+60 ℃. Humidity level 3K4, maximum temperature change of 1 K/min, no derating below 2000 m altitude, 5% derating every 1000 m from 2000 to 3000 m, pollution level 2. In terms of vibration, the continuous vibration during operation and transportation is 3 g, with a frequency of 10 to 2000 Hz; the impact operation is 10 g, with a half sine of 11 ms. If the mechanical stress is greater, anti vibration components must be installed.

Security Chain: STOP, CRR, and Security Interface

The safety features of KR C5 micro comply with Category 3 and Performance Level d of EN ISO 13849-1, while also meeting SIL 2 of EN 62061. The premise is that all safety related mechanical and electromechanical components undergo functional testing at start-up and at least once every 12 months, including emergency stop devices on smartPAD, external emergency stop devices, enable devices on smartPAD, enable devices on Commander, external enable devices, and safety outputs of discrete safety interfaces.

Safe stops are divided into STOP 0, STOP 1 (HRC), STOP 1 (path marking), and STOP 2. STOP 0 immediately cuts off the drive and applies the brake, and the robot stops in a path guided manner. STOP 1 (HRC) is used for human-machine collaboration, where the robot switches to soft control with enhanced damping to reduce external forces and stop. The robot will deviate from its path, cut off the drive and apply the brake after coming to a stop; The safety controller monitors the Cartesian speed and external shaft torque, and applies the brake and cuts off the drive no later than 1 second later. STOP 1 (path marking) maintains path braking, cuts off the drive and applies the brake when stationary, and applies the brake and cuts off the drive no later than 1.5 seconds later. STOP 2 does not cut off the drive, does not apply the brake, and maintains a braking ramp deceleration path.

CRR, also known as Controlled Robot Retraction, is an optional operating mode when the safety controller stops the robot due to the following reasons: the robot violates the axis specific or Cartesian monitoring space, the tool direction exceeds the allowable range, the robot violates collision detection or maximum TCP force monitoring, one or more axes are not mastering, one or more axis positions are not mastering confirmed, one or more joint torque sensor calibration is not confirmed, the maximum Cartesian speed is exceeded, and the axis maximum torque is exceeded (such as in compression situations). After switching to CRR mode, the robot can move again. If the reason for stopping no longer exists and there are no further stop requests within 4 seconds, the operation mode will automatically switch to T1. The speed limit in CRR mode is the same as T1: program validation maximum 250 mm/s, jog maximum 250 mm/s, manual guidance does not limit speed but is limited by the safety guidance speed monitoring in the safety configuration.