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APPENDIX A: TECHNICAL SPECIFICATIONS
875DP/500DP/500HV DUAL PULSE
RESISTANCE WELDING
POWER SUPPLIES
A-18
990-290
Charge (Process) Inhibit
Shorting Pin 9 to Pin 11 will close the charge (process) inhibit line and prevent recharging of the
capacitor bank. The charge inhibit line is used during remote schedule selection to prevent the
capacitors from recharging to a higher energy schedule when loading a lower energy schedule. This
saves the time required to discharge the capacitors unnecessarily. The charge inhibit line must be closed
immediately after the power supply fires and before the 60 millisecond commutation pulse has ended.
The line must then be opened before the next schedule can be executed. Charge inhibit can also be used
instead of [RUN] to remotely clear any error stop alarm. Short Pin 9 to Pin 11 momentarily and
immediately open the short to clear the alarm.
Remote Weld Schedule Selection
Refer to figure A-6. To use this feature, connect the seven control lines from a user supplied, normally
open contact (open collector or TTL logic levels can also be used) to mating CONTROL SIGNALS
connector Pins 1, 2, 3, and 4. Connecting any one of these inputs to Pin 11 will cause the power supply
to load the weld schedule defined by the corresponding pin combination, immediately after the initiation
switch closes. Weld schedules are selected according to the binary pattern shown in the table A-3.