Weller WMD 3 Betriebsanleitung Seite 34

5-second stages for other tools. Approx. 4 seconds after the last input, the display will auto-
matically switch to the actual value for the set channel.
Timer function re-set
Every channel has a timer. The timers can be set and reset independently. Select the desi-
red channel with the "1-2-3" key and confirm with the keys "UP", "DOWN" or "TIMER". The
programmed setpoint will be displayed for a short time, and the display will then return to
the actual value.
Timer function switch-off
The desired channel is selected by means of the `1-2-3' key, then the `TIMER' key is pres-
sed. Set the value to "000" with the "DOWN" key. The timer function is now deactivated.
Key switch
If the key-operated switch is in the locked position, all input functions are blocked.
Therefore, only inquiries are possible in this position.
Reset function
This function is used to return the control unit to the basic setting. It is necessary to switch
off the unit, wait approx. 10 seconds, then hold down the keys "TIMER" and "1-2-3" while
switching on the unit until the self-test is concluded and "FSE" (Factory Setting) appears
on the display.
All temperature settings should now be at 350˚C, the timer function should be switched off
and the air supply set to 50%.
Temperature offset
The temperature control of the WMD 3 is harmonised to the average value of the available
range of solder tips. Tolerance is ±9°C for soldering and de-soldering bits. For hot-air tools,
tolerance is ±30˚C. Individual channels can be re-calibrated for special applications.
For this purpose, the temperature offset (difference between the measuring instrument dis-
play and the control unit display) is ascertained by means of the corresponding measure-
ment peaks and an external temperature measuring instrument. The adjustment function
can be activated by simultaneously pressing the `TIMER' and `1-2-3' keys, which is indica-
ted by flashing of the `C' symbol. The temperature offset can be corrected within the range
± 40˚C by simultaneously pressing the `UP' or `DOWN' key. If no modifications are made,
the display will automatically change to the actual value after the keys are released.
Warning: For the purpose of cooling the unit, the pump motor is equipped with a fan.
Adequate air circulation should therefore be ensured.
Maintenance
For operation with the hot gas pencil:
The air flow-rate of the pump is affected by dirty filters. Consequently the main filters for
`VACUUM' and `AIR' should be regularly inspected and replaced as required. For this pur-
pose, 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 ena-
bles a high degree of efficiency 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 cleaned regularly. This operation includes emptying the flux con-
tainer, replacing the glass tube filter and checking the seals. If the glass cylinder sealing
faces are sealing satisfactorily, 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 cleans 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.
Various types of de-soldering operation can be fulfilled by the range of suction nozzles.
Suction nozzles can be easily changed over, and the fitting tool is integrated in the cleaning
tool. Suction nozzles should be replaced only in the hot state.
Illustration (cleaning tool, cleaning procedure and replacement of suction nozzles),
see page 77
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