In Resistive Load Operation, The Output Voltage Is Not Regular - Cebora SPOT 3500 Service Manual

CEBORA S.p.A.

3.3.4 - In resistive load operation, the output voltage is not regular.

For the following tests use a resistive load capable of circulating a current greater than 100
Aac, for example 0.02 ohm, and capable of supporting the consequent current, considering that
the rated open-circuit output voltage is approximately 7 Vac.
OUTPUT VOLTAGE TEST ON RESISTIVE LOAD.
Type of Switch
operation lever (1)
position
manual Right
manual Right
automatic, Left
pulse train
automatic, Left
single stroke
automatic Left
MANUAL MODE TEST.
Switch (1) in manual mode (lever to the right), power source output terminals = voltage
q
values and waveforms as in the table, with start button pressed.
Holding down the start button, turn the potentiometer (3) and make sure the line of the output
q
voltage waveform changes in a linear, non-abrupt fashion, between the minimum and
maximum values of fig. 5.2.2 and 5.2.3.
♦ Check the wiring between connector CN4 on the control board (27) and static
switch (14).
♦ Check the wiring between the switch (1) and connector CN3, control board (27):
CN3, terminals 1 and 2 = 0 ohm (contact closed), terminals 3 and 4 = > kohm
(contact open) = manual mode.
If incorrect, check the status of the switch (1) and replace if defective.
♦ Check the connections between the secondary transformer circuit (26) and output
terminals of the power source. If you find loose or burnt connections, clean
thoroughly and tighten, or replace any damaged terminals or components.
♦ Replace static switch (14).
♦ Replace control board (27).
AUTOMATIC PULSE TRAIN OPERATING MODE TEST.
Switch (1) in automatic mode (lever to the left), switch (11) in pulse train mode (lever
q
down), power source output terminals = waveform as in fig. 5.2.4, with start button pressed.
Holding down the start button, turn the potentiometer (2) and make sure the pulse packet
q
length changes to the maximum duration of 1 second per packet (the pause between the pulse
packets remains constant, 400 msec.).
3.302.047
NOTE
Switch Potentiometer
lever (11) (2) position
position
- -
- -
down at minimum
up at maximum
- at minimum
Correct?
YES
NO
Potentiometer Output
(3) position voltage
Vac
at minimum 2
at maximum 7
- -
- -
- -
12
Waveform
fig. 5.2.2
fig. 5.2.3
fig. 5.2.4
fig. 5.2.5
fig. 5.2.6
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