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DESCRIPTION OF THE WORKING CYCLE
The welding control unit gun Working cycle carried out by means of the START 1 input is different from the multifunction
gun working cycle carried out by means of START 2 input. The Working cycle is determined by the user through the
adjustment of the different programming parameters, different for both gun and multifunction gun. These parameters
indicate the operating times and the current regulations characterising the working cycles whenever performed
consecutively. The following drawings show the execution order of the programmed functions for the two different working
cycles.
The symbols refer to the programming parameters described in the following paragraph.
Due to safety reasons, the microprocessor does not start the welding cycle when the cycle start signal is
enabled during the welder connection; in this case disable the control device and activate it again. Any micro-
interrupts or excessive voltage drop blocks the control rather than altering the operation; turn the machine off
for 1" and then turn it on again.
DESCRIPTION OF PARAMETERS
All the following parameters indicating a period of time are expressed in mains cycles, also called periods. The main
frequency defines the duration of a cycle:
Mains frequency of 50 Hz, 1 period = 20 ms
Mains frequency of 60 Hz, 1 period = 16,6 ms.
PARAMETERS CONCERNING THE GUN WORKING CYCLE (WHITE COLOUR
)
SQUEEZE
The SQUEEZE time is used with the pneumatic gun only. It is the time interval between the beginning of the electrodes
closing and the beginning of the welding cycle. The set value should be long enough to allow the electrodes to reach the
correct tightening force before the beginning of the welding cycle. Insufficient squeeze time causes the formation of
flashes between the electrodes and the metal at the beginning of the welding cycle; this inconvenience could lead to an
inconsistent quality level. Should the cycle start signal be disabled during the squeeze time, then the sequence is
interrupted.
When using a hand-operated gun, set this parameter to 01 to obtain the fastest working cycle.
SLOPE
The SLOPE parameter describes the time during which the programmed value of welding power is reached. The starting
value of this slope always corresponds to the minimum power, while the final value corresponds to the value of power
being programmed in parameter CURRENT. The slope speed is automatically calculated by the microprocessor
according to the programmed values.
WELDING TIME
The WELDING TIME parameter indicates the current flow duration. It will be carried out with the same value of power
indicated in parameter CURRENT. When the pulse operation is on, this parameter signals the duration of each pulse and
it could reach a maximum value of 25 periods.
CURRENT
The value expressed in CURRENT indicates the welding operating power.
COLD TIME
The COLD TIME parameter is used in the pulse operation and indicates the time elapsing between one welding pulse
and the next one.
IMPULSE NUMBER
The IMPULSE NUMBER parameter indicates the number of impulse used for the welding process. When the parameter
is set to 0, the pulse operation is shut off. The duration of each impulse corresponds to the time set in the WELDING
TIME parameter