SPECS EBE-1, Руководство пользователя

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Chapter
5
Maintenance
5.1 Replacing the filament
WARNING:
Take care with old filaments. They are very brittle having recrystalised during use.
The broken ends are very sharp
Replacing the filament is particularly simple due the filament assembly, which allows
the filament to be removed from the evaporator as part of the filament assembly and
replaced in a more convenient working location.
To remove the filament assembly:
(1) Unscrew the M2 grub screws which retain the copper current leads
(2) Remove the two/four M2 slotted screws which retain the Macor filament holder.
(3) Lift up the Macor filament holder, taking care to feed the filament out through the
slot in the copper block and at the same time pulling the copper current leads out of
the end of the filament rods.
(4) The filament wire itself is Ø 0.25 mm tungsten wire, which can be bought by the
reel from suppliers such as Advent or Goodfellow.
(5) Undo the 2-off M2 grub srews in the end of the filament rods, which secure the fila-
ment wire and remove the old filament.
(6) Insert a new filament and tighten the grub screws. Avoid twisting the filament as
far as possible. Trim the excess leads as close as possible to the filament rods using
good quality side-cutters. Shape the filament as necessary into a symmetrical ring. The
ring (diameter should be ~13 mm).
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