In KUKA's cobot range, the cleaner the room, the bigger the robot you have to buy

KUKA now lists seven builds of its LBR iisy collaborative arm, and two of them are factory cleanroom versions rated up to ISO Class 3. Both sit at the top of the payload range: the 11 kg long-arm model and, since 2025, the 15 kg compact one. The 3, 6 and 8 kg arms have no cleanroom variant at all. That ordering runs against the work. Cleanroom duty is concentrated in semiconductor handling, optics, medical device assembly and laboratory automation, and those are places where benches are short, equipment is packed tightly and a small arm is usually the right tool. In this family a buyer who needs ISO Class 3 has no small option: the entry point is a 1300 mm arm rated for 11 kg. The same inversion shows at the other end of the range. The smallest LBR iisy, the 3 kg R760, is the only member rated IP30 — protection against solid bodies above 2.5 mm and no protection against water whatsoever. Every model from 6 kg upward is IP54. In the family table the row looks like any other, but the practical meaning is a hard boundary: the 3 kg arm belongs on an assembly bench, not in a machining cell with coolant mist, grinding dust or wash-down cleaning. So the least protected robot is the smallest, and the most protected is the largest, with nothing in between. The cleanroom versions also arrived late. The standard 11 and 15 kg models were announced in June 2022 and available from the end of that year; the 6 and 8 kg builds joined during 2023. The first cleanroom variant, the 11 R1300 CR, appears in the manufacturer's own product listing during 2024, and the 15 R930 CR only in 2025 — three years after the arm it is based on. KUKA publishes no announcement date for either, so those years are lower bounds rather than launch dates. One detail is worth keeping in the manufacturer's favour. KUKA quotes the ISO Class 3 rating without a speed or payload condition, because the CR is a separate catalogue number rather than a standard robot asked to slow down. That is the more expensive way to sell a cleanroom cobot and the one that survives reading the small print. All seven builds are now in the wujec.ai catalogue.