PEC MACC, Руководство пользователя, Страница: 17 / 26

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For example, the output of a 1000 Amp @ 12 Volt converter will be held constant -+10 Amp from
1.2 Volts to 12 Volts. The voltage limit control is designed to reduce load burning due to
overvoltage and prevent power interruption to the load. Any increase in load resistance will result
in a decrease of output current and the converter will be limited at its rated voltage output.
This automatic current control can be used in operations such as hard chrome where thickness must
be accurately controlled. It can eliminate costly grinding and stripping operations. An automatic
current control can be used in any type of operation where variations in solution, temperature,
thickness and contact area will adversely affect the work being done.
3.3 Converter Operation
3.3.1 Turn-On Procedure
1. Make sure all open panels are closed before the converter is energized.
2. Close the main disconnect (customer).
3. Turn the "output adjust" knob completely counterclockwise.
4. Switch the "control on-off" switch to the "off" position.
5. Press the "start" button to energize the converter.
6. See Section 3.3.2 , 3.3.3 , or 3.3.4 for particular operation required by the application.
3.3.2 Automatic Voltage with Current Limit Operation Adjustment Procedure
All converters are shipped in the voltage mode of control unless otherwise specified at time of
order.
A. The "current density adjust" pot must be turned completely counterclockwise for automatic
voltage operation. This pot is located on the front panel of integral control units or inside the
remote cabinet for remote control units. To adjust, remove the locknut and turn the pot with a
screwdriver completely counterclockwise, then replace and tighten the locknut.
B. The "limit adjust" pot should be turned completely clockwise. At this setting the converter
current output will be limited at its full rated value. If a lower current limit point is desired, then
turn the pot counterclockwise to the desired setting. For example, setting the pot at midpoint
will limit the current to approximately half the rated output current. This pot is located on the
front panel of integral control units, or inside the remote cabinet for remote control units. To
adjust, remove the locknut, turn the pot to desired setting with a screwdriver, then replace and
tighten the locknut.
C. Turn the "output adjust" knob completely counterclockwise.
D. Energize the converter as outlined in Section 3.3.1 .
E. Switch the "control on-off" to the "on" position.
F. Adjust the "output adjust" knob to the desired voltage level. The converter will hold the desired
voltage level constant for varying load conditions.
NOTE : Desired voltage level setting must be between 10% to 100% of the full
rated output voltage of the converter.