Troubleshooting; The Power Source Does Not Start, Lamp (6) Off - Cebora SPOT 3500 Service Manual

CEBORA S.p.A.

3.3 - Troubleshooting.

ANY INTERNAL INSPECTIONS OR REPAIRS MUST BE CARRIED OUT BY QUALIFIED
BEFORE REMOVING THE PROTECTIVE GUARDS AND ACCESSING INTERNAL
PARTS, DISCONNECT THE POWER SOURCE FROM THE MAINS.
Items in boldface describe problems that may occur on the machine (symptoms).
Operations preceded by this symbol refer to situations the operator must determine (causes).
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♦ Operations preceded by this symbol refer to actions the operator must perform in order to
solve the problems (solutions).

3.3.1 - The power source does not start, lamp (6) off.

MAINS SUITABILITY TEST.
No voltage for mains protection.
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♦ Eliminate any short-circuits on the connections between power cable, switch (5),
transformer (26) and static switch (14).
♦ Check the wiring between terminals 8 - 9, 11 - 12 of CN4 on the control board
(27) and static switch (14).
♦ Make sure that the static switch (14) is not short-circuited. Replace if necessary.
♦ Make sure the windings of the transformer (26) are isolated from one another and
from earth. If insulation leaks, replace the transformer (26).
♦ Make sure that the static switch (14) is properly engaged. For this test, insert the
oscilloscope (with memory if possible) on the power source output terminals, set
the power source to automatic mode, switch lever (11) to the left, and press the
gun start button while holding it free in the air (open circuit operation). In this
condition, the static switch (14) must be engaged simultaneously with the peak of
the sine curve of the mains voltage (fig. 5.2.1), thus approximately 90° - 100°
before it crosses 0. If necessary, set the trimmer RV2 on the control board (27).
More accurate adjustment is possible by measuring the current at the primary
circuit of the transformer (26), using a TA and oscilloscope, and adjusting the
trimmer RV2 until the first current peak is as high as subsequent peaks. For this
test, we recommend making several attempts, moving the trimmer RV2 each time
to seek out the ideal position.
♦ Replace control board (27).
♦ Mains not suitable to power the power source (ex.: insufficient installed power).
3.302.047
WARNINGS
PERSONNEL.
NOTE
Correct?
NO
YES
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21/12/00