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APPENDIX A: TECHNICAL SPECIFICATIONS
875DP/500DP/500HV DUAL PULSE
RESISTANCE WELDING
POWER SUPPLIES
A-2
990-290
Table A-1. Pulse Characteristics
Model
Pulse Transformer
Connections
Capacitor
Bank
Rise
Time
Pulse
Length
Pulse Height
SHORT (Parallel)
1.7 ms
6.8 ms
9.5 V – 10.5V
MEDIUM
6000
ȝ
F
2.2 ms
7.8 ms
8.5 V – 9.4 V
500DP
LONG (Series)
2.7 ms
9.2 ms
7.3 V – 8.0 V
SHORT (Parallel)
1.7 ms
6.8 ms
19.0 V – 20.9 V
MEDIUM
6000
ȝ
F
2.2 ms
7.8 ms
17.0 V – 18.7 V
500HV
LONG (Series)
2.7 ms
9.2 ms
14.6 V – 16.1 V
SHORT (Parallel)
2.0 ms
9.1 ms
11.5 V – 12.7 V
MEDIUM
10500
ȝ
F
2.7 ms
10.2 ms
10.2 V – 11.2 V
875DP
LONG (Series)
3.7 ms
16.5 ms
7.8 V – 8.6 V
Weld Fire Lockout
Output of the error amplifier inhibits the firing circuit during the charge and turndown intervals. This
helps prevent poor welds caused by firing the power supply before the capacitor bank is properly
charged or discharged
Line Voltage Regulation
Maintains voltage on the capacitor bank within ± 0.25% of setting for a ± 13% change from the nominal
rated line voltage.
Turndown Circuit
When voltage from the error amplifier exceeds that required to turn off the charging circuit, a resistor is
connected across the capacitor bank, discharging the bank to the required level. The turndown circuit
deadband is approximately 0.6% of full scale voltage.
Line Failure Turndown
When input power is interrupted, a turndown resistor is automatically connected, discharging the
capacitor bank.