The PLZ-U Series Electronic Load Unit is a compact,
high-performance, multichannel electronic load unit that has
three operation modes: constant current, constant
resistance, and constant voltage.
The PLZ-U consists of a frame and load units. Load units are
inserted into the frame (control section) for operation. The
PLZ-30F and PLZ-50F Frames can accommodate up to 3 channels
and 5 channels of load units, respectively.
The current capacity or power capacity can be increased
through a parallel operation of load units. The load units
can be combined to produce a power capacity from 75 W to 750
W (when five PLZ150Us are installed into the PLZ-50F).
in addition to high-speed response and highly precise preset
resolution, various functions are provided including the
soft start function, variable slew rates, switching
function, ABC preset memories, four setup memories, and
Because the PLZ-U comes standard with GPIB and RS-232C
communication functions, it can easily be incorporated into
various test and inspection systems. The communication
functions are useful for testing batteries, DC/DC
converters, switching power supplies, and multi-output power
In addition to the advanced constant current, constant
resistance, and constant voltage functions, the PLZ-U Series
Electronic Load Unit offers wide variety of other features.
■ Compact and light
Compact and light weighing only approximately 11 kg and 17
kg for 3 channels and 5 channels, respectively.
■ High-speed response
In constant current mode, a current rise and fall slew rate
of 2.4 Α/μ8 (PLZ150U) is possible (converts to a rise and
fall time of 10 μβ). Simulations that closely resemble a
real load are possible by using the PLZ-U as a load for DC
power transient response tests and as a dummy load
M High precision and high resolution
Three ranges are built into the PLZ-U achieving both wide
dynamic range and high resolution. The PLZ-U provides
displays with up to 5 digits for voltage, current, and power
measurement functions as well as minimum preset resolutions
of 10 μΑ (PLZ70UA) and 20 μΑ (PLZ150U).
■ Variable slew rate
The current slew rate can be varied continuously in constant
current mode and constant resistance mode. This feature
allows the suppression of transient voltage drops due to the
wiring inductance that occurs when a load is switched and
transient voltages of constant voltage power supplies, etc.
■ Multi channels
Up to five and three channels can be installed into the
PLZ-50F and PLZ-30F, respectively. Each channel is isolated
and can be used independently or linked with each other.
Different units (PLZ150Us and PLZ70UAs) can be installed in
■ Low noise
High reliability and low noise have been achieved by the
adoption of a heat sensing variable speed fan and the
enhanced cooling structure.
■ Large capacity
Parallel operation is possible on up to five adjacent load
units of the same type.
Five PLZ70UAs installed in PLZ-50F operating in parallel
produce 375 W.
Five PLZ150Us installed in PLZ-50F operating in parallel
produce 750 W.
■ 0 V type
The PLZ70UA is a 0 V input operating voltage unit. This
feature is a must for single cell tests of fuel cells.
Moreover, the operating voltage of semiconductor devices is
decreasing more and more due to the reduction of the power
consumption and miniaturization of the semiconductor
process. The PLZ70UA can be used to evaluate the power
supplies for these types of applications.