WRx 시리즈
Utilizing Magna-Power's patented Active Resistance Technology (US Patent 9,429,629) in combination with the company’s internally manufactured microchannel water-cooled heatsinks, the WRx Series addresses high power DC applications where exhaust heat control is essential. The WRx Series greatly increases power density compared air-cooled alternatives. An integrated solenoid controls the flow of water to avoid condensation. Full power can be achieved using conventional water, with water inlet temperatures up to 25°C.
Magna-Power's Active Resistance Technology utilizes a switched binary matrix of resistances and MOSFET network, combined with Magna-Power's new MagnaLINK™ distributed DSP architecture, the WRx Series delivers the same features and performance as traditional electronic loads, at a fraction of the price. In addition to the 16-bit precision voltage, current, resistance, and power control modes, the WRx Series also provides a rheostat control mode, allowing direct control of the product's internal resistance network.





MagnaLINK™ Distributed Digital Control
Magna-Power’s MagnaLINK™ technology provides distributed Texas Instrument DSP control across power processing stages inside the MagnaLOAD DC electronic load. This technology follows a significant internal development cycle from Magna-Power to provide a unified digital control platform across its electronic loads and power supplies, featuring fully digital control loops, adjustable control gains, programmable slew rates, digital master-slaving, and many new advanced control technologies.
All ARx Series MagnaLOADs come with the following interfaces:
- Front panel knob, keypad, and menu system
- 25-pin configurable external user I/O, including a high-speed analog input
- Front and rear USB and rear RS-485 or optional Ethernet and IEEE-4888 GPIB
When in standby or diagnostic fault, the DC input bus is disconnected via a switching device.
Finally, with a dedicated +5V interlock input pin and included +5V reference on all models, external emergency stop systems can be easily integrated using an external contact.
Six Flexible Operating Modes
To accommodate a variety of DC sources, all ARx Series MagnaLOADs come with many configurable control modes, including:
- Voltage Mode
- Current Mode
- Power Mode
- Resistance Mode
- Shunt Regulator Mode
- Rheostat
Preference for DC regulation is given to the parameter in the selected mode within the programmed set-points. Using the MagnaLOAD's set-points and trip settings, the product can configured to either trip with a fault when a limit is exceeded or to cross-over into a different regulation state.
Shunt Regulator Mode turns the MagnaLOAD into a high-speed smart braking resistor, engaging the DC input only when a specified voltage and exceeded by a user-defined percentage, while limiting the shunt current to a programmed set-point.
Configurable External User I/O
Beyond the front panel and computer controls, all MagnaLOADs come standard with a 25-pin D-Sub connector designated as the External User I/O. This connector provides:
- 8 Digital Outputs
- 4 Digital Inputs
- 4 Analog Outputs
- 4 Analog Inputs
All the analog-digital I/O ports are configurable, allowing the user to select which parameters they want to control and monitor. This configurable I/O scheme reduces complexity, eases PLC integrationand allows control parameters from various interfaces simultaneously.
The MagnaLOAD's configurable analog inputs provide 0-10V programming from PLCs and external D/A converters.

MagnaWEB Software Interface
Magna-Power's next generation software interface, MagnaWEB, provides intuitive and user-friendly web-browser based controls for programming and measurement read-back of the MagnaLOAD's activity. Virtually all of the MagnaLOAD's available functions can be controlled and monitored from the MagnaWEB software over any of product's installed communication interfaces.
MagnaWEB uses a server-client software model to provide access to the MagnaLOAD from nearly any device and operating system. Install and run the MagnaWEB software locally on Windows then, using a web browser, access the server connected to the MagnaLOAD from a variety of devices including other desktops, tablets or smart-phones.
Active Resistance Technology: A New Era for Electronic Loads
The ARx Series utilizes Active Resistance Technology to deliver performance consistent with conventional electronic loads, but at a fraction of the price and with the ability to directly switch passive resistors on-the-fly.
In Magna-Power's Active Resistive Technology, switched resistors are placed in series with MOSFETs. High-performance DSPs simulatenously control both dissipation elements in harmony. Assuming the power across the shunt resistor is insignificant, the power dissipated in load resistor R1 is IL x VR1 and the power dissipated in MOSFET Q1 is IL x VQ1. The resistors can be operated at higher temperatures than the MOSFETs, simplifying cooling requirements of the passive elements. Keeping VQ1 small and VR1 large lowers system costs in comparison with purely semiconductor electronic loads. Adjusting the value of resistor R1 is accomplished with a binary switching matrix. Finally, keeping the resistor switching increments small and over a wide range maintains the smallest voltages across the linear modules and over the widest operating range.
The advantage of resistive loads are reliability and cost per watt for dissipating power, while the advantage of MOSFET loads is speed of performance and the ability to dissipate power over a wide operating range. Active Resistive Technology blends switched resistance with MOSFETs to significantly lower the product's cost, add new control modes, while still delivering 16-bit precision and high-accuracy performance
Front Panel - Standard
Front Panel - Blank Panel (+BP) Option
STOP: Disables the DC input bus
BACK: Moves back one level in the menu
ENTER: Selects the highlighted menu item
CLEAR: Removes the product from a faulted state
LOCK: Locks the front panel, with password protection available
Model Ordering Guide
Model Ordering Guide
There are 3 different models in the WRx Series spanning power levels: 12.5 kW.
Use the following ordering guide and models chart to define the best model for your application.
WRx Series Models
There are 3 different models in the WRx Series spanning power levels: 12.5 kW. To determine the appropriate model:
- Select the desired Max Voltage (Vdc) from the left-most column.
- Select the desired Max Current (Adc) from the same row that contains your desired Max Voltage.
- Construct your model number according to the model ordering guide.
Model | Maximum Power | Maximum Voltage | Maximum Current | Package Type | Minimum Voltage |
---|---|---|---|---|---|
WRx12.5-200-130/UI | 12.5 kW | 200 Vdc | 130 Adc | Rack-mount | 2.5 Vdc |
WRx12.5-500-52/UI | 12.5 kW | 500 Vdc | 52 Adc | Rack-mount | 3.0 Vdc |
WRx12.5-1000-26/UI | 12.5 kW | 1000 Vdc | 26 Adc | Rack-mount | 5.0 Vdc |
Specifications
The following specifications are subject to change without notice. Unless otherwise noted, all specifications measured at the product's maximum ratings.
Specification | Value |
---|---|
AC Input Voltage
1Φ, 2-wire + ground |
85 to 265 Vac (UI: Universal Input) |
AC Input Frequency | 50-60 Hz |
AC Input Isolation | ±1500 Vac, maximum input voltage to ground |
Specification | Value |
---|---|
Front Panel Programming | Aluminum rotary knob with encoder, keypad, or up-down arrow for single bit control |
Computer Interfaces
Standard |
USB Host (Front): Type B USB Host (Rear): Type B RS485 (Rear): RJ-45 MagnaLINK™: RJ-25 x 2 |
Computer Interfaces
Optional |
LXI TCP/IP Ethernet (Rear): RJ-45 GPIB (Rear): IEEE-488 |
External User I/O Port
Analog and Digital Programming |
25-pin D-sub DB-25, female Referenced to Earth ground; isolated from the DC input See User Manual for pin layout |
Specification | Value |
---|---|
Resolution
All Modes |
16-bit, 0.0015% |
Accuracy
Programming and Measurement |
Voltage: ±0.1% of full scale voltage rating Current: ±0.2% of full scale current rating Power: ±0.3% of full scale power rating Resistance: ±0.3% of full scale resistance rating |
Rise/Fall Time
Maximum |
Voltage Mode: 100 ms, 10% to 90% full scale voltage rating Current Mode: 2 ms, 10% to 90% full scale current rating Power Mode: 100 ms, 10% to 90% full scale power rating Resistance Mode: 40 ms, 10% to 90% full scale resistance rating |
Trip Settings Range |
Over Voltage: 10% to 110% of full scale voltage rating Under Voltage: 0% to 110% of full scale voltage rating Over Current: 10% to 110% of full scale current rating Over Power: 10% to 110% of full scale power rating |
Specification | Value |
---|---|
Digital I/O |
Digital Input Voltage: 5V Digital Input Impedance: 10 kΩ Digital Monitoring Voltage: 5V, 32 mA capacity Digital Reference Voltage: 5V, 20 mA capacity |
Analog I/O |
Analog Sampling Rate: 2 kHz Analog Programming Voltage: 0-10 V Analog Programming Resolution: 12-bit, 0.025% Analog Monitoring Voltage: 0-10 V, 3 mA capacity Analog Monitoring Impedance: 0.005 Ω Analog Monitoring Accuracy: 0.05% of full scale Analog Reference Voltage: 10 V, 20 mA capacity |
Specification | Value |
---|---|
Racking Standard
12.5 kW Models |
EIA-310 |
Rear Support Rails
12.5 kW Models |
Included |
Size and Weight
12.5 kW Models |
4U 7” H x 24” W x 19” D (17.8 x 60.9 x 48.2 cm) 165 lbs (74.8 kg) |
Specification | Value |
---|---|
Ambient Operating Temperature | 0°C to 50°C |
Storage Temperature | -25°C to +85°C |
Humidity | Relative humidity up to 95% non-condensing |
Air Flow | Front air inlet, rear exhaust |
Specification | Value |
---|---|
Water Connection Provided | 12.5 kW Models: 1/2” NPT male inlet and outlet |
Maximum Inlet Temperature | 25°C |
Maximum Inlet Pressure | 80 PSI |
Minimum Flow Rate | 12.5 kW Models: 1.5 GPM |
Specification | Value |
---|---|
EMC | Complies with European EMC Directive for test and measurement products |
Safety | Complies with EN61010-1 |
CE Mark | Yes |
RoHS Compliant | Yes |
Options and Accessories
The following are options and accessories developed specifically for Magna-Power's WRx Series
Accessories
External accessories and integration services are available for Magna-Power products
Integrated Options
Standard integrated options are available for Magna-Power products, allowing the product's performance and communication interfaces to be tailors to the specific application.
EtherCAT
Option Code: +ECAT
Availability:
EtherCAT communication protocol and dual RJ-45 interface for high-performance communication in factory automation, motion control, and robotics
EtherNet/IP
Option Code: +EIP
Availability:
EtherNet/IP communication protocol and dual RJ-45 interface with EIS profile for industrial automation, commonly used in Allen Bradley, Schneider Electric, and Omron PLCs
IEEE-488 GPIB
Option Code: +GPIB
Availability:
IEEE-488 General Purpose Interface Bus (GPIB) communication interface providing full command support and compatibility with other GPIB devices
LXI TCP/IP Ethernet
Option Code: +LXI
Availability:
TCP/IP Ethernet communication protocol and single RJ-45 interface, certified to the LXI Class C standard, for socket communications using conventional computer networks
Modbus-TCP
Option Code: +MTCP
Availability:
Modbus-TCP communication protocol and dual RJ-45 interface with full command set support as Modbus commands
PROFINET
Option Code: +PROF
Availability:
PROFINET communication protocol and dual RJ-45 interface for industrial automation, commonly used in Siemens PLCs
Downloads
The following downloads are for the WRx 시리즈: