Troubleshooting guide

7
DESCRIPTIONSECTION 2
Figure 2-1. Volt-Ampere Curves
 THE V
REF
DESIGNATION SHOWN ON THE TYPICAL V/A CURVES (ABOVE) CORRESPONDS
TO AN ABSOLUTE VOLTAGE REFERENCE SIGNAL (0 TO 10 VOLT RANGE) FROM THE CNC
(CUTTING) CONTROL THAT ESTABLISHES THE PRECISE OUTPUT ARC CURRENT OF THE POWER
SOURCE. THESE CURVES ARE DERIVED FROM THE FORMULA I
ARC
= 50 V
REF
2.5 Power Source Connections
A. For operation of two ESP-400 Power Sources in parallel, there is one master power source and one slave power
source. The master power source utilizes the standard transformer configuration, and the slave power source
utilizes an alternate configuration for 180° phase shift (see Figure 2-2).
The master power source is the one utilizing the 19-conductor cable from the front of the flow control and is also
the one to which the pilot arc wire is connected. The slave power source utilizes the 19-conductor cable, P/N 33940,
connected to the designated receptacle at the back of the flow control.
In addition to reconnecting the main transformer and considerations of connecting the flow control and pilot arc wire,
the slave unit is different from the master unit in the following ways:
1. The boost bridge fuses must be removed from the slave power source. The boost bridge is located on the base
under the main bridge. Access to the fuses is made from the left side with the left side panel removed. (Left
side is viewed while standing in front of the power source looking at the meters.)
2. The black wire connecting the negative of C21 to the positive of C22 must be removed from the positive of C22
in the slave power source. The wire should be looped by attaching both ends to the negative of C21. This will
eliminate the concern of the loose end shorting to other conductors. (C21 and C22 are the two large capacitors
located on the base near the input power strain relief. (See Figure 5-2.)