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APPENDIX A: TECHNICAL SPECIFICATIONS
875DP/500DP/500HV DUAL PULSE
RESISTANCE WELDING POWER SUPPLIES
990-290
A-9
Weld Functions
Three weld functions can be selected: Basic, repeat and rollspot. The duration of the squeeze (system
option), cool (rollspot) and off time (repeat) periods can be set between 0 and 9.99 seconds
.
Head Type
The power supplies can be used with a manual, user actuated, or air actuated weld head. Air actuation
means that the power supply will provide a 24 or 115 VAC output which can be used to control an air valve
(solenoid) on an air actuated weld head. The power supplies can automatically detect the presence of a
Unitek Peco actuated weld head.
You can indicate the presence of a user-supplied non-Unitek Peco air head by jumpering Pin 4 to Pin 2 on
the VALVE DRIVER connector. If Pin 4 is not connected to Pin 2, the power supply assumes that a manual
head is being used. The power supply determines whether it is connected to an air or manual head
whenever it enters the RUN state. The options menu can be programmed to override the automatic selection
feature.
Squeeze Time
For air head operation, squeeze time is the delay from the footswitch closure until the start of the weld
period. For manual head operation, squeeze time is the delay from firing switch closure until the start of
the weld period. The delay can be set from 0.00 to 9.99 seconds.
Cool Time
Cool time is the time between welds. In the rollspot function, the electrodes are wheels. The cool time
and the rotational speed of the wheels determine the distance between welds. An air head will not open
until the footswitch is released. Cool time can be set between 0.00 and 9.99 seconds.
Hold Time
Hold time is the delay from the end of the weld pulse until the head valve opens. Hold time applies only
to an air head. The delay can be set from 0.00 to 9.99 seconds.