UPGRADED VENTILATION CRATES FOR LHC RACKS S Brachet
UPGRADED VENTILATION CRATES FOR LHC RACKS S. Brachet, A. Gaddi, H. Sabba CERN – Experimental Physics Depart. MOTOR-VENTILATOR ZIEHL-ABEGG SELF-LOCKING CONNECTOR CRATE WITH SHIELDED MOTORS FRONT PANEL MONITORING CARD & SMOKE DETECTOR 7 th Common ATLAS CMS Electronics Workshop for LHC Upgrades Poster Session Magnetic field tolerant up to 1400 Gauss: Plastic blades / Shielded motors Easily replaceable motor-ventilator units. Plug-and-play design. Backward compatible monitoring board & DSS interfaces. Standard supply at CERN Store. ACES 2020 – Electronics Workshop for LHC Upgrades
Historical Background • The turbine crates for LHC electronics racks have been developed between years 2000 and 2006 to provide a reliable ventilation system, essentially for those racks located in the LHC Experimental Caverns, where a significant magnetic stray field is present. • The base-lines of these units are plastic-blades fans and massive iron shields around fans motors and sensitive PCBs. • The crates, due to the heavy shielding, are uncomfortable to install/remove from the top of the rack, causing serious safety issues, specifically in case of racks with difficult access, as it is often the case on the detectors structures. Andrea Gaddi, CERN EP Department 2
Project Development • At CMS a project was launched to investigate either the possibility to reduce the mass of the shielding iron or to extract the fan units (the only component requiring periodical maintenance and/or repair) without being obliged to remove the full crate from the rack. • Unfortunately all the different alloy tested to replace iron as basematerial for the shield didn’t give any significant advantage in terms of weight, thus all the effort was concentrated towards a new design of the crate allowing for an easy extraction of the fans from the crate. Andrea Gaddi, CERN EP Department 3
Solutions Retained • A first prototype was built modifying an existing crate and, after intensive testing under magnetic stray field, it has been retained as base-line for the design of a new crate-chassis. Andrea Gaddi, CERN EP Department 4
Solutions Retained • The new chassis includes longitudinal rails that allow the insertion and centering of the fan units inside the crate, including a self-locking electrical plug on the back. • Thus fans can be inserted/extracted by simply removing the crate front panel, without any additional complex and heavy handling. MOTOR-VENTILATOR ZIEHL-ABEGG SELF-LOCKING CONNECTOR FRONT PANEL CRATE WITH SHIELDED MOTORS MONITORING CARD & SMOKE DETECTOR Andrea Gaddi, CERN EP Department 5
Logistics & Procurement • The last objective of the project has been to include the new crates into the CERN Store supply chain. • The process is now complete and the new chassis are available on edh with their own scem codes. Andrea Gaddi, CERN EP Department 6
- Slides: 6