The compensation function of secondary current is used to
facilitate the welding process of oxidised sheets and rods. The
pieces oxidation blocks the current flow during the first welding
phase, thus limiting, in a different way depending from the welding
process, the real time of current flow. The compensation function
controls the welding current by means of a coil located inside the
secondary circuit. Until the welding current does not exceed a pre-
set limit, the welding time is automatically extended up to a limit of
99 cycles. In this way it is possible to carry out welding processes
with an always constant real time of current flow.
If, after having reached the 99 welding periods limit, the current
limit is not exceeded, the control unit will indicate that the welding
process has not been correctly carried out by displaying the E4
error, and will block the welder functioning. To restore the
functioning, press a push-button. The current limit is adjusted, by
means of an internal trimmer, by the welder manufacturer. The
standard value is usually about 1500=2000 A. By means of JP2
jumper, located on the card, is possible to disable this function:
COMPENSATION FUNCTION OF SECONDARY CURRENT
This function allows to obtain the best machine line current
balance. Simultaneously press push-buttons
and
for
about one second to carry out the adjustment. The CURRENT
COMPENSATION JUMPER
JP2
ON OPEN
OFF CLOSED
AUTORETAIN JUMPER
JP1
ON CLOSED
OFF OPEN
function lamp flashes and the display shows the actual set value.
As usual, the adjustment is carried out by pressing push-
buttons and . The value can be set from 35 up to 99.
When the programming is over, press or . As this
adjustment is carried out by the welder manufacturer, the user
does not need to modify this value.
AUTORETAIN FUNCTION
As usual, when the current flow starts, the welding control unit
ends the welding cycle even if the cycle start control is disabled.
This function is called autoretain function. In TE 90 it can be
disabled to use the control unit for manual-operated welders. In
this case, if the cycle start signal is disabled during the machine
cycle, the control unit will immediately stop the welding current
flow and disconnects the solenoid valve. In both cases the control
unit immediately stops the cycle and opens again the electrodes
whenever the cycle start signal is disabled during the squeeze
phase. The autoretain function selection is carried out through
jumper JP1 located on the card:
DELAY FUNCTION OF FIRST PHASE SHIFT
While using electric-operated welders this function should always
be enabled in order to prevent any welding cycle from having a
welding time other than the set one.
CONTROL PANEL PILOT LIGHTS
It signals that the mains voltage is on.
It signals that the main cycle start control is on.
It signals that the additional cycle start control is on.
It signals that the block control with pressure only is on. This input is activated by the first stage of a
foot control or by other devices that should hinder the welding process (such as for example, flow
switches, pressure switches or the interlocking system of another welder).
It signals that the control unit is generating the control impulses for SCR.
It signals that the solenoid valve is on.
ERROR LIST
MESSAGE
CAUSE
CURE
The value of one of the stored parameters exceeds
the preset limits. This could be caused by a loss of
data due to any interference or wrong functioning.
Press a push-button to cancel the error. Check all the
values set in the parameters and correct them if
necessary. Apply to the after-sale service if the trouble
occurs frequently.
The welding time is set to a value higher than 25 and
pulses operating mode is activated. This parameter
cannot be higher than 25 in the pulse mode operation.
Press a push-button to cancel the error. Set the
welding time to a value lower or equal to 25 cycles.
Pulses operating mode is activated and the total
welding time (welding time x impulse number) is
higher than the limit of 150 cycles. Do not exceed this
value so as not to overheat the machine.
Press a push-button to cancel the error. Decrease the
welding time or the impulse number so that their
product is lower than 150 cycles.
The compensation function is enabled and the control
unit has extended the welding time up to the
maximum limit of 99 periods. The set welding time has
not been carried out with a welding current higher than
the limit.
Press a push-button to cancel the error. Before restart
the welding process check the welding conditions. If
the pieces are too oxidized they must be cleaned.
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