(ET) Interesting, that's what eats E15 relays....

[Chris Zach <cz alembic crystel com>]

Interesting evening. I put a hand-wired fuse holder in for the control 
fuse, fired up the tractor, and it still works normally. Which is good.

However since it was dark I noticed a little flash from under the dash. 
Opened the front panel so I could watch the relays and went from forward 
3 to zero. Nothing. Then I went into reverse. Nothing, FR relay clicked. 
Then I went into reverse, nothing. Then I went back into neutral and 
moved the lever over.

*bang* flash in the relay box. And it suddenly hit me:

What is happening is that in going from forward to reverse even when not 
going *into* reverse is that the FR relay is changing state. And if 
there is a residual current in the field from the armature spinning down 
it's going to flash the relay when it happens.

I'll look into this more tomorrow, but I am wondering if the problem is 
not just going from forward to reverse while the motor is spinning, but 
going from forward or reverse to neutral *and moving the lever in the 
left/right direction* that causes an arc.

If so that's going to be more complicated to fix. But it would explain 
why these relays fuse themselves with such aplomb, it's human nature to 
get yourself ready to go in the direction you want to go.

Interesting.

C