Table of Contents
Advertisement
3-46 When the center tap of an Auto-Series combin¬
ation is grounded, coordinated positive and nega¬
tive voltages result.
This technique is commonly
referred to as "rubber-banding" and an external ref¬
erence source may be employed if desired.
Any
change in the internal or external reference source
(e.g. drift, ripple) will cause an equal percentage
change in the outputs of both the master and slave
supplies.
This feature can be of considerable use
in analogue computer and other applications, where
the load requires a positive and a negative power
supply and is less susceptible to an output voltage
change occuring simultaneously in both supplies
than to a change in either supply alone.
3-47
PARALLEL OPERATION
3-48
Normal Parallel Connections (Figure 3-10).
Two or more 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.
The output CURRENT
controls of each power supply can be separately
set.
The output voltage controls of one power sup¬
ply should be set to the desired output voltage; the
other power supply should be set for a slightly
larger output voltage.
The supply set to the lower
output voltage will act as a constant voltage source;
the supply set to the higher output will act as a
constant current source, dropping its output voltage
until it equals that of the other supply.
The con¬
stant voltage source will deliver only that fraction
of its total rated output current which is necessary
to fulfill the total current demand.
Figure 3-10.
Normal Parallel
3-49
AUTO-PARALLEL OPERATION (Figure 3-11)
3-50
Two or more power supplies can be connect¬
ed in an Auto-Parallel arrangement to obtain an
output current greater than that available from one
supply.
Auto-Parallel operation permits equal cur¬
rent sharing under all load conditions, and allows
complete control of the output current from one
master power supply.
The output current of each
slave will be approximately equal to the master's
output current regardless of the load conditions.
Because the output current controls of each slave
are operative, they should be set to maximum to
prevent the slave reverting to constant current op¬
eration; this could occur if the master output cur¬
rent setting exceeded the slave's.
3-51
Additional slave supplies may be added in
parallel with the master/slave combination.
All
the connections between the master and slave #1
are duplicated between slave #1 and the added
MASTER
MASTER
Figure 3-11.
Auto-Parallel Operation,
Two Units and Three Units
3
Advertisement
Table of Contents
