PEC Miniverter, Руководство пользователя

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For example, with a 100 amp @ 12 volt unit, the output voltage will be held constant -+ 0.12 volts
over a range of operation from 10 amp to 100 amp. The voltage will remain constant throughout
the operational cycle and will eliminate the costly burning or overplating which can result from
widely varying load voltages.
Protection of the converter from D.C. overloads is provided for by the automatic current limiting.
Any decrease in load resistance above the converter current rating will result in a decrease of output
voltage and the converter output current will be limited at its maximum rated current.
In some plating processes where a current interruption by a D.C. overload device can result in
costly stripping and replating, the current limiting feature automatically prevents the overload from
damaging the converter while maintaining continuous operation at reduced output voltage.
B. Automatic Average Current Density Control with Current Limiting
The need for average current density
control is due to the fact that the
current in a plating system does not
increase in direct proportion as the
plating area is increased, even
though the plating voltage is held
constant. It is necessary to increase
the voltage as work area is added in
order to maintain the proper average
current density.
The automatic average current
density control increases the
converter's output voltage as a
greater amount of bus current is
sensed. This is done by converting a
current signal to a proportional
voltage and adding it to the basic
operating voltage. A current limiting feature automatically prevents an overload from damaging
the converter while maintaining continuous operation at reduced voltage.
Figure 4 Current Density Control