Section 3: Power Supply Operation
3.7 Responding to Fault Conditions
0101-8242-0, Rev. C
3-11
CV-6SLX User Manual
3.6.4 Adjusting the Filament Bias Current and the Emission Current
Adjusting the Filament Bias Current
The bias current can be adjusted only by varying the FILAMENT CURRENT REQUEST signal,
which is supplied Pin 12 on the FPS front panel connector J101 (see Table 2-2).
NOTE
When the FIL BIAS SET SELECT signal (supplied via J101 Pin 5) is low, the Autobias circuit of the FPS
controls the bias current. When the FIL BIAS SET SELECT signal is high, the operator can control the
bias current from the control system’s user interface.
Adjusting the Emission Current
The emission current can be adjusted only by varying the EMISSION CURRENT REQUEST signal,
which is supplied via Pin 10 FPS rear panel connector J101 (see Table 2-2).
3.7 Responding to Fault Conditions
3.7.1 Responding to Latching Power Supply Faults
The following signals must be supplied, in the order given below, in order for the HV to be
switched back on after a latching Power Supply fault has occurred:
•
a RESET signal, supplied either by the user pressing the front panel HV OFF button or by
remote input, via Pins 10 and 11 on HVPS rear panel connector J4
•
an HV ON input, supplied via HVPS J4 Pins 8 and 9.
The remote HV ON signal can be supplied either from an EBC (see section 3.5) or from a PLC-
based system controller. In many cases, it will be necessary to trace and correct the cause of a
latching fault before the HV can be switched back on. Then the RESET and HV ON signals must
be supplied, as described above. Note that the gun is not automatically switched off when
latching Power Supply (i.e., HVPS faults occur) and that FPS faults that cause the gun to be
switched off do not cause the HV to be switched off. Section 3.7.2 describes this user-response
sequence with respect to a specific latched-fault condition.
For detailed functional descriptions of the front panel LEDs that indicate latching faults, see
section 5.2.3. For diagrams illustrating the troubleshooting logic that apply to a various fault
conditions, see section 5.3. For detailed troubleshooting procedures, see section 5.4.
3.7.2 Special Note Regarding Arc-Related Fault Conditions
During normal operation, the
ART/OUT OF REGULATION
LED on the power module front
panel will flash intermittently as arcs occur. The flashing will increase in frequency as arcs
increase in frequency. Each time it does so, the
HV OUT OF REGULATION
LED will also turn
amber for two seconds. For an illustration of this Subthreshold arcing state, see Figure 3-11.
