Elecraft KPA500 Fuse Installation - Manual (Page 2)

 Install the proper fuses in the block. Use 12A fuses for 115V and 6A fuses for 230V. Use normal
(fast-blow) size 3AG fuses. Both 12A and 6A fuses are supplied in marked envelopes. Note that the
fuse block has a spring contact that presses one end of the fuse outward where it will rest against an
electrical contact when the fuse block is reinstalled in the holder.
 Replace the fuse block so that the correct mains voltage appears in the window in the cover. When
replacing the fuse block in the holder squeeze the fuses against the spring contact so they will slide
into the holder.
 Be sure the fuse block is fully seated in the holder as shown below before trying to close the door.
You may feel a lot of resistance just before it is fully seated as the fuses reach the contacts inside the
holder. That is normal.