MPE DP SERIES II, Operating And Service Manual

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3.8 Parallel Operation
Two or more DP Series power supplies can be connected in parallel to obtain a total output
current greater than that available from one power supply. The total output current is the sum of
the output currents of the individual power supplies. Each power supply can be turned on or off
separately.
A parallel connection involves attaching the positive terminals of all supplies to be paralleled to
the positive point of the load and attaching the negative terminals to the negative point of the
load. The output current controls of each power supply can be separately set. The output
voltage control of one power supply (master) should be set to the desired output voltage; the
other power supply (slave) should be set for a slightly higher output voltage. The master will
act as a constant voltage source; the slave will act as a constant current source, dropping its
output voltage to equal that of the master.
3.9 Series Operation
Two or more power supplies, or master/slave modules, can be connected in series to obtain a
total output voltage greater than that available from one power supply. The total output voltage
is the sum of the output voltage of the individual power supplies. Each power supply can be
turned on or off separately. The master/slave modules turn on and off together when the slave’s
external control is enabled.
Caution: No plus or minus voltage should exceed 1000 Vdc with respect to
ground for models rated 1000 V less. No plus or minus voltage should exceed
4000 Vdc with respect to ground for models rated greater than 1000 V.
3.9.1 Series Operation - Direct
The simplest series connection involves attaching the negative terminal of the first supply, or
master/slave module, to the positive terminal of the second supply. An output shorting jumper is
provided for interconnecting the modules. The load is connected between the positive terminal
of the first supply and the negative terminal of the second supply. The output current controls of
each power supply are operative and the current limit is equal to the lowest control setting. If
any one output current control is set too low with respect to the total output current, the series
power supplies will automatically crossover to constant current operation and the output voltage
will drop.
3.9.2 Series Operation - Master/Slave
Master/slave series operation permits equal voltage sharing under all load conditions and allows
complete control of output voltage from one master power supply.
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