A press release for an industrial computer arrived a few days ago and it included an image of a metal box with four standard USB connectors on the front. Anyone who has accidentally tugged on a wire and unplugged a USB cable from a PC knows these connectors–and connections–won’t last long in industrial environs. I’ve also seen “Industrial-Grade USB Hubs” with standard PC USB sockets. Better cable connectors exist, but you’d never know it based on what some companies tout as “industrial-grade” or “rugged-grade” equipment.
Here’s an example of what a company calls an industrial-grade USB hub. Would you trust industrial equipment with standard USB connectors?
The people at Sealevel Systems created the SeaLATCH USB socket and plug to ensure a connection a loose cable cannot undo. The SeaLATCH socket attaches to a panel with screws–something many USB connectors do not do. In addition, it provides a threaded hole that accepts a thumbscrew on USB cable plugs that Sealevel also manufactures. The socket will also accept standard type-A USB plugs. See the image below:
The back of a SeaLATCH socket provides a standard 4-pin Molex connector so you can easily connect to a USB port on a motherboard or in embedded computers. Sealevel also provides the SeaLATCH sockets pre-mounted on PCI frames or adapters so you can fit them in PCs with PCI cards. For information, visit: http://www.sealevel.com/store/sl-pm-usb-panel-mount-adapter-with-sealatch-type-a-port.html.
The SeaLATCH doesn’t protect against moisture, dirt, or dust, though. If you need a connector and socket pair that does, you can find rugged and waterproof assemblies and cables at: http://www.usbfirewire.com/usb-rugged-waterproof-zinc.html. Amphenol also sells rugged USB connectors as well as hinged caps that protect unused rugged USB sockets. Here’s the link I found to the Amphenol products on the Mouser Web site: http://www.mouser.com/Search/Refine.aspx?Ne=254016&N=1323038+8648632+4294764080.
During a search for more rugged USB connector suppliers I found several that advertise “rugged” devices, some with a “high-retention option,” but either they don’t explain it or don’t show how it works. In my opinion, for industrial use, you can’t beat a USB connector that screws into something or locks together with a mating device. That goes for other types of connections, too. After all, we have had screw-together RS-232 connectors for a long, long time. –Jon Titus
Disclosure: Over the years I have worked with Tom O’Hanlan at Sealevel Systems but I have no financial interest in the company or its businesses.