Equipotential Bonding; Operating Guidelines - Weller WMD 3 Manual De Uso

English
purpose, unscrew the filter cover, extract the dirty filter and
insert a new original Weller filter cartridge. Check for correct
seating of the cover seal, insert the compression spring and
screw the filter cover back on with a light pressure.
For operation with the desoldering tip:
The de-soldering head, heating element and sensor together
constitute a unit, and this enables a high degree of efficien-
cy to be achieved. Any damage to the coated surface will
cause corrosion.
Therefore, the de-soldering bit should be parked only in the
original WELLER holder. The de-soldering head should be cle-
aned regularly. This operation includes emptying the flux
container, replacing the glass tube filter and checking the
seals. If the glass cylinder sealing faces are sealing satisfac-
torily, then full suction power will be obtained. Dirty filters will
affect the air flow-rate of the pump. Consequently, the main
filter for 'VACUUM' and 'AIR' should be inspected regularly
and replaced if necessary. For this purpose, unscrew the fil-
ter cover, take out the dirty filter and insert a new original
WELLER filter cartridge. Ensure correct seating of the cover
seal, insert the compression spring and screw the filter cover
back on again with a slight pressure. The `VACUUM' filter cle-
ans the extracted air of flux vapours and should therefore be
inspected more frequently.
Warning: The vacuum pump will be damaged if operated
without a filter.
Different suction nozzles solve a lot of desoldering pro-
blems. The appropriate tool for changing the suction
nozzles is integrated in the cleaning tool (005 13 500 99).
A brief rotary movement (approx. 45°) is all it takes to
quickly change the suction nozzles. When inserting and
locking the suction nozzle, press lightly against the hea-
ter.
Change and clean the suction nozzle only when it is
warm. Use the cleaning tool to clean the suction nozzle
bore and suction tube.
Illustration (cleaning tool, cleaning procedure and repla-
cement of suction nozzles), see page 83
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4. Equipotential bonding

The various circuit elements of the 3,5 mm jack bush make
4 variations possible:
Hard-grounded:
Equipotential bonding:
Potential free:
Soft-grounded:
5. Operating guideline
For operation with the hot gas pencil:
The hot air supply is free of static charge and can be set to
as much as 10 litres/minute. The hot gas pencil is equipped
with a non-return valve which protects the hot gas pencil
from damage in the event it being inadvertently connected to
the `VAC' nipple. Nozzles are screwed into the heating unit.
To change nozzles over, use the SW8 internal hexagon key
and lock with a `C' spanner.
Caution: Max. thread depth is 5 mm. A longer thread will
cause damage to the heating element.
For operation with a desoldering tip:
The utilisation of additional solder wire is important in the
desoldering procedure. This will ensure good tinning of the
suction nozzle and improved flow characteristics in the old
solder. Care should be taken that the suction nozzle is per-
pendicular to the plane of the circuit board in order to obtain
the best suction performance. All of the solder must be fully
liquid. During the desoldering procedure, it is important to
move the connection pin of the component in a circular
motion in the bore. If the solder has not been completely
removed after the first suction procedure, the soldering point
should be re-tinned before a further attempt at de-soldering
is made. The correct choice of suction nozzle size is impor-
tant. A rule of thumb is that the internal diameter of the suc-
tion nozzle should be consistent with the diameter of the hole
in the board.
Pump overrun when using the vacuum function
When desoldering, the vacuum function can be set to conti-
nue running (1 sec.). The factory setting does not active this
over-run.
Switching on the pump overrun
Switch off the unit. Press the „up" and „down" buttons when
switching the unit back on, until the self-test is finished. A „-
1-" will appear on the display. Release the buttons.
No plug (delivery form)
With plug, equalizer at
center contact (impedance
0 ohms)
With plug
With plug and soldered
resistance. Grounding with
set resistance value.