Vibration resistant, waterproof enclosure - Page 1
Forum section: electronics / projects

author: EEBlackSheep
author_rank: Contributor
timestamp: October 20, 2019, 03:53:41 am
content: I am putting together an ECU for a dirt bike. Lots of vibration, lots of water, and from time to time, submersion. Sadly I am not an engineer (comp sci - dont shoot me!). I am looking for engineering guidelines for circuit assembly and enclosure design for vibration resistance and waterproofness (IP68?).thanks for any helpDC

author: e100
author_rank: Frequent Contributor
timestamp: October 20, 2019, 01:00:14 pm
content: Visit a scrap yard and find a wreck from which you can extract the ECU enclosure, wiring harness and connectors.As for components, just don't buy from Ebay or Aliexpress as they will either be fake or recycled from old gear.

author: EEBlackSheep
author_rank: Contributor
timestamp: October 20, 2019, 02:09:26 pm
content: Thanks for the tip, but I am looking for electronics engineering guidelines for IP68/Vibration resistance rather than salvaging an existing ECU enclosures. Existing ECU enclosures are too big for a dirt bike. I also want to understand the best practices for build IP68/vibration resistant designs.

author: Gyro
author_rank: Super Contributor
timestamp: October 20, 2019, 02:23:24 pm
content: You'll probably do as well as anything with this style of sealed Aluminium diecast enclosure (check the Technical datasheet on the page for more detail)...https://uk.farnell.com/rose/01-08-18-06/enclosure-aluminium-80x175x57mm/dp/4744081?st=diecast%20enclosureThey have an O-ring and lip seal, with all mounting and lid fixing screws outside the seal. They're rated IP66 but with additional sealant you could probably make it up to IP68. Some thread lock on the fixing screws would get you the vibration resistance.

author: Kasper
author_rank: Frequent Contributor
timestamp: October 20, 2019, 03:57:59 pm
content: Digikey and probably other electronic component vendors have lots of enclosures. And you can filter for enclosures with IP-68.https://www.digikey.ca/products/en/boxes-enclosures-racks/boxes/594?k=&pkeyword=&sv=0&pv707=360152&sf=1&FV=-8%7C594&quantity=&ColumnSort=0&page=1&stock=1&pageSize=25Conformal coating or potting the electronics can help too. I once bought a 'new' brake light for my dual sport from a reputable store. It died first ride so I took it apart and it looked corroded and had multiple broken solder joints. I think it was an old repaired unit. Took pictures and got refund then fixed some solder joints and conformal coated the PCB and it lasted atleast until the bike was stolen acouple years later.

author: mzzj
author_rank: Super Contributor
timestamp: October 20, 2019, 04:08:17 pm
content: Quote from: Gyro on October 20, 2019, 02:23:24 pmMaking the enclosure vibration proof is easy. Lot harder to make the insides also vibration proof, especially on something like dirt bike that vibrates and rattles like crazy.

author: DBecker
author_rank: Frequent Contributor
timestamp: October 20, 2019, 04:15:53 pm
content: Check out the hardware discussions at rusefi.com.What size ECU are you planning? How many pins on the connector? Do you want a cast aluminum case, or a plastic top with stamped bottom?

author: Dr_Neoo
author_rank: Contributor
timestamp: November 01, 2019, 12:41:50 am
content: Deutsch sell some small waterproof enclosures with integrated connectors:https://www.te.com/usa-en/products/connectors/automotive-connectors/intersection/deutsch-pcb-enclosures-and-headers.html?tab=pgp-storyTo make your design vibration resistant try to use low mass components. Also try to use frequent fastening points from the pcb to the chassis to avoid flexing. Dampening can be a possibility but simulating or calculating what is needed is not trivial.