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Magna-Power Electronics
Programmable DC Power Supplies
Technology and Feature Overview
Innovative and Scalable
Magna-Power Electronics programmable DC power supplies
combine the best of DC power processing with microprocessor embedded control. A combination of high and medium
frequency power processing technologies improves response,
shrinks package size, and reduces cost. All Magna-Power
Electronics DC power supplies are current-fed and are more
tolerant to abusive loads than conventional switching power
supplies. This technology allows the power supply to operate
under short-circuit conditions, open-circuit conditions and
everything in between.
The programmable DC power supplies offer both master/
slave parallel and series operation. This enables two or more
power supplies to be placed in parallel for increased output
current or in series for increased output voltage, within the
unit’s isolation limits. With master/slave operation, power
supplies operate at near equal voltage and current. The process of master/slaving power supplies is plug & play with the
use of Magna-Power Electronics UID47 option, which can be
added at any time. 
All supplies can operate as a voltage source or current
source depending on the control settings and load conditions.
If the power supply is operating as a voltage source and
the load increases to a point beyond the current command
setting, the power supply automatically crosses over to current mode control and operates as a current source at that
setting.

Designed for Safety
Magna-Power Electronics programmable DC power supplies have extensive diagnostic functions—all of which,
when activated, take command to shut down the system.
Diagnostic functions include phase loss, excessive thermal
conditions, over voltage trip, over current trip, fuse clearing,
and program line. Program line monitors externally applied
analog set point signals to insure they are within the specified range. Upon a diagnostic fault condition, main power
is disconnected and the diagnostic condition is latched into
memory. Pressing the clear key clears the memory. All diagnostic functions can be monitored through the rear connector and software. Furthermore, control functions can also be
set through the rear connector to allow simultaneous control
of one or more power supplies.
The power supplies have three levels of over voltage/current
protection: shutdown of controlling insulated gate bipolar
transistors (IGBTs), disconnect of main power and input
fuses. After an over voltage/current trip condition, the supply fault must be cleared.
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Isolated External I/O for Automation
Using the rear isolated 37-pin I/O connector, the programmable power supplies can be completely controlled and
monitored using external signals. The voltage, current, over
voltage and over current set points are set by applying a
0-10V analog signal. Each diagnostic condition is given a
designated pin, which reads +5V when high. Reference +5V
and +10V signals are provided, eliminating the need for
external voltage signals and allowing the use of dry contacts.
Also, the power supply features a normally closed external
interlock, which when enabled, allows the power supply to
be tied in with other emergency stop equipment. All these
pins are isolated to earth-ground as standard—no additional
isolation equipment or options necessary.

Fully Programmable
The Magna-Power Electronics programmable DC power
supplies can be programmed and monitored using three possible sources:

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Stepless front panel programming knobs
External analog/digital signals
Computer interface through included software, LabVIEW, or other programming environemnt
The power supply can be programmed to have its control
functions accessible from the front panel, rear connector,
RS232 (standard), LXI TCP/IP Ethernet (+LXI), IEEE
488 GPIB (+GPIB), USB Edgeport (+USB), or RS485DSS
(+RS485) communications. The included IVI driver enables
programming in a variety of software environments, including: Visual C++, Visual C#, Visual Basic .NET, Visual
Basic 6.0, LabVIEW, LabWindows/CVI, MATLAB, Measure
Foundry, and Agilent VEE Pro. Basic programming requirements are satisfied by the instrument’s supported Standard
Commands for Programmable Instruments (SCPI). Sensing can be established at the output terminal of the power
supply or through a rear remote sense terminals for sensing
at the load. Even calibration has been simplified with front
panel access to digital calibration potentiometers.

Attention to Power Quality
All Magna-Power Electronics power supplies contain circuitry to work harmoniously with other power equipment.
Step-start contactors are used to keep inrush current below
full scale operating current. Filter components lower current
harmonic content emanating from the power supply and increase power factor to levels beyond 90%. Every power supply is tested at 90% to 125% nominal line to insure satisfactory operation even under the worst line voltage conditions.

Electronic Output Stage
The novel electronic output stage (XR/TS/MS Series) utilizes
near constant power loading under all conditions via an
electronic bleed resistance. This electronic bleeder means
stability under all operating conditions and faster fall times,
without affecting the overall system efficiency.
Magna-Power Electronics • Programmable DC Power Supplies