I dropped a wire to ground while wiring a thermometer/clock into our WS31. I had to pull every fuse in the box one-at-a-time to find the I blew. It turned out to be one of these large "J case" fuses. Since, when did you have to give up the price of a burger & fries to buy a fuse?! Sheesh
**NEW** Littlefuse Jcase 20 amp Cartridge Fuse Rated 32 volts pkg 2 | eBay