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APPENDIX A: TECHNICAL SPECIFICATIONS
875DP/500DP/500HV DUAL PULSE
RESISTANCE WELDING POWER SUPPLIES
990-290
A-11
Footswitch Weld Abort Off
With FOOTSWITCH WELD ABORT OFF selected, the welding sequence is initiated by a single,
momentary, closure of the initiation switch. Opening the initiation switch during the welding sequence
will
not
terminate the welding sequence.
The initiation switch must open and re-close in order to start the next sequence. FOOTSWITCH WELD
ABORT OFF is used in automated process control systems where operator intervention is not an issue.
Firing Switch Type
The power supply can use as an input signal either a:
x
Single pole, single throw switch
x
Double pole, double throw (3-wire) switch, or an
x
Optical switch.
The input signal will indicate when the weld head has applied the proper force to the workpiece. Weld
heads with single pole firing switches should be connected to the MECHANICAL FIRING SWITCH
connector. A 3-wire switch or optical firing switch, either of which should be connected to the OPTICAL
FIRING SWITCH connector, eliminates switch bounce (which causes false triggering), and should be used
when the welding speed exceeds 1.5 welds per second.
Firing Circuit
The firing circuit requires external contact closure or low logic level for firing. Internal filtering
prevents premature firing due to radio frequency interference. The power supply will automatically
detect that the system is using a 3-wire switch whenever it enters the RUN state if Pin 1 is shorted to
Pin 2.
Switch Debounce Time
Single pole mechanical firing switch contacts 'bounce' when they close. The switch debounce time
feature allows you to specify that the firing switch must remain closed for 0, 10, 20 or 30 milliseconds
before the weld period can be initiated. The power supply will automatically set the switch debounce
time to 0.0 milliseconds whenever a 3-wire or optical switch is selected.
Mechanical Firing Switch Cable
This cable is 5 feet long. It is a Type 2/C, 600 volt cable containing two shielded, twisted 22 AWG
conductors of high-flex stranded wire. The firing switch connector is a 2-pin Amphenol 80-MC2FI