Valco Cincinnati VC3500, User Manual

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VC3500/VC3700 Troubleshooting Manual
Valco Cincinnati Page 5
System Level Description
Input Power
PEM (Power Entry Module)
The PEM is a VDE/IEC approved module that performs several functions; voltage selection,
on-off control, over-current protection, and EMI filtering. The PEM accepts an IEC320
approved line cord to provide the VC3500 either 230 VAC or 115 VAC.
Voltage selection is accomplished by removing the fuse drawer and replacing it so that the
correct voltage is displayed in the fuse door window. The fuse drawer places the primary
windings of transformers XF1, XF2, and XF3 in series when in the 230vac setting, and in
parallel when in the 115vac setting. The double pole fuse drawer accepts either 5x20 mm
IEC fuses, or 1/4 x 1 1/4 inch UL fuses. For line-to-neutral operation, use the shorting clip
(jumper) and one fuse. The shorting clip must be on the left side of the fuse drawer (when
rotated to read the correct voltage). For line-to-line operation, use two fuses.
For operation from a single phase power main, a single fuse should be installed on the 'hot'
side of the line only and a shorting jumper should be installed on the 'neutral' side. For
operation from a three-phase power main, dual fuses should be installed.
The PEM provides on-off control through a double pole switch.
Finally, a filter is utilized to prevent line noise from interfering with the operation of the
VC3500, and to prevent high frequency signals generated within the VC3500 from appearing
on the power lines.
XF1 (Transformer 1) A41-175-24
The primary winding of Transformer 1 is connected to the PEM and so will have either 230
VAC or 115 VAC applied to its primary terminals. The secondary voltage of 12 VAC (dual
secondary windings in parallel) is delivered to J2 of the Valve Driver Boards where it is
converted to a variable 5 to 12 vdc for the
Valve Hold Voltage .
XF2 (Transformer 2) A41-80-36
The primary winding of Transformer 2 is connected to the PEM and so will have either 230
VAC or 115 VAC applied to its primary terminals. The secondary voltage of 36 VAC (dual
secondary windings in series) is delivered to J2 of the Valve Driver Boards where it is
converted to 56 vdc for the
Valve Peak Voltage .
XF3 (Transformer 3) A41-80-28
The primary winding of Transformer 3 is connected to the PEM and so will have either 230
VAC or 115 VAC applied to its primary terminals. The secondary voltage of 14 VAC (dual
independent windings) is delivered to J1 of the Power Supply board where it is converted to
several DC voltages for use throughout the system.