Alexandre, thanks for the photo, I thought it might be in there. Bill & Bill, thanks for thinking it through with me.
The whole sordid story borders on the stupid, but we were anchoring at night in 25 knots in a crowded anchorage, with the wind opposite the current. We decided to set the anchor into the wind and I asked Peg to use the bowthruster to keep the bow from slewing around. Here's the stupid part: I didn't retract the bowthruster right away. We backed down on the anchor and immediately the current took us opposite to our set and the chain went under the boat.
We tried to raise the thruster when it appeared the chain was clear, and it would not raise (jack screw). I went below and there was nothing but a bit of "electric smell", something got hot, but it could have been the heavy use of the motor at the bascule bridge (the bridge tender insisted that we stay within 200 feet of the bridge or he wouldn't open it! He made us wait one 30 minute opening because in his opinion we were too far away.)
Out of concern for further damage during the night I disconnected one jack screw cable so I could lever the bow thruster to the up position. There isn't any visible damage to the tube.
I checked the breaker on the 24 volt panel but it was on, not tripped. The breakers in the fwd cabin port locker don't list the thruster, only "Boom; Mast; Windlass; Jib & Windlass", but I flipped them anyway and no joy.
I'll be diving at slack tide late this morning to check out the damage...if there is any (fingers crossed!). In the meantime I wanted to check out the fuse.
Thanks for the help everyone.