The MDL4U Series is a multi-channel modularprogrammable electronic load system. Sevendifferent modules of programmable DC loadsranging in power from 200 W to 600 Wprovide users the flexibility to test a wide rangeof power sources from multi-output DCpower supplies to batteries, fuel cells, andphotovoltaic arrays. The mainframe consists of a controller and fouropen slots that can be populated with anycombination of modules up to 2400 W (up to4800 W with mainframe extension). Thehigh-performance electronic load modules ofthe MDL4U Series are capable of operating inconstant current (CC), constant voltage (CV),constant resistance (CR), and constant power(CW). Easily edit the load’s parameters such as voltage,current, slew rate, and width via the front panel.Increase productivity by saving your testparameters into any one of the 101 memoryareas for quick system recall. Additionally, theMDL4U Series provides 16-bit resolution as wellas numerous protection modes and a power-onsystem self-test to ensure the reliability of yourtesting.For remote communication, the MDL4U Seriesprovides LAN, USB (USBTMC-compliant),RS232, and GPIB standard interfaces thatsupport SCPI command protocol.

High performance architecture
Equipped with a high-performance microprocessorin every mainframe and module, the MDL4U Seriesprogrammable DC electronic load utilizes aparallel architecture that provides highmeasurement speed. Additionally, a simultaneousload on/off operation can be performed throughthe front panel, analog control terminal, or remoteSCPI command. This configuration allows thesystem to control modules synchronously andincreases productivity in testing.

Powerful communication interfaces
The MDL4U Series mainframe offers all the latestoptions to the user for remote communication.Connect via GPIB, Ethernet, USB, or RS232 tocarry out data communication through SCPI andUSBTMC standard communication protocols tocontrol all your electronic load modules from aPC.

Modular design

With the removable module design, you can choosesuitable load modules to modify the systemaccording to your requirements. This designallows for multiple channels and is ideal fortesting several units, especially power supplieswith multiple outputs. At the same time, all loadmodules can be configured to work independently.All load modules, including the high power 500 Wand 600 W modules can fit in one slot. Unlikecompetitor models that require two slots for highpower modules, the MDL4U Series offers a one-slotform factor for all modules..

Adjustable slew rate

In constant current mode, users can control therate or slope of the change in current in atransient response test. Set the slew rate to asslow as 0.0001 A/μs or as fast as 2.5 A/μsdepending on the module and selected currentrange.

Transient operation

Transient operation enables the module toperiodically switch between two load levels.A power supply’s regulation and transientcharacteristic can be evaluated by monitoringthe supply’s output voltage under varyingcombinations of load levels, duty cycle, and slewrate. The MDL4U Series can simulate theseconditions up to 25 kHz

Low Voltage Operation

The MDL4U Series can operate at low voltages for applications such as fuel cell and solar cell testing

List mode

Not limited to just switching between two levels,list mode lets you generate more complexsequences of input changes with several differentlevels. Up to 7 groups of list files can be savedin the mainframe. Each list can contain up to 84steps with a minimum width time of 20 μs perstep.

Automatic test mode
The MDL4U Series can execute multiple testsequences across all channels. Sequences can becascaded, and each step can be programmedwith upper and lower limit values. When appliedin automatic production testing, you can easilyjudge whether the test parameters of yourdevices are within the specification limits andadjust your process according to the GO/NGverdict.