Figure 4-2 Dual-Gun Cv-12Slx Hvps Rear Panel - ferrotec Temescal CV-12SLX User Manual

4.2 HVPS Theory of Operation
Two AC line phases from the Inverter board feed the primary of step-down transformer T2. In
208 VAC units, T2 is wired with jumpers for a 1:1 ratio. In 400 VAC units, it is wired for a 2:1
ratio. T2 powers the AC input of PS1, the +24 VDC auxiliary power supply. The +24 VDC output
of PS1 connects back to the Inverter board and provides low-voltage power to the other board
assemblies in the power module.
4.2.2 Power Module Grounding
Grounding is provided through two threaded studs mounted on the unit's rear panel (see Figures
4-1 and 4-2). The grounding stud labeled GND must be connected to an earth ground for safety.
The other threaded grounding stud, labeled RF GND, provides a ground return for the HV output
and must be properly connected to provide a low-impedance ground (for instructions, see
section 2.5.1). Internally, ground wires are connected together by a ground block mounted to
the bottom panel.
4.2.3 Temperature Control
Temperature inputs come from two separate devices, thermostat S2 and IC sensor U1, which
are connected to the Inverter board. Thermostat S2 opens when the Inverter board's heat sink
rises above a preset temperature. U1 generates an analog voltage scaled to the temperature of
the heat sink near the Inverter board's IGBTs. Both sensors feed the over-temperature fault
circuitry. Cooling of internal components is provided by +24 VDC fan B1 mounted on the rear
panel. The fan draws air in through the front panel grille and exhausts it through the rear of the
unit. The fan features an integral jammed-rotor sensor, which is designed to sense when the fan
has stopped spinning and to trigger an over-temperature fault in that event.
CV-12SLX User Manual

Figure 4-2 Dual-Gun CV-12SLX HVPS Rear Panel

4-2
Section 4: Theory of Operation
0101-8292-0, Rev. C