Delta Elektronika SM6K: Bidirectional 6 kW DC Power with a New Firmware Update

Delta Elektronika’s programmable SM6K Series DC power supplies operate as both precision voltage and current sources and regenerative electronic loads. They deliver 6 kW of power, feature an extended constant-power operating range, and offer flexible interfaces for laboratory, development, and automated test systems. A new firmware update is also available for the series. Please contact us for more information about the update or to discuss the right configuration for your application.

One unit for source and sink operation

In source mode, the SM6K supplies regulated DC voltage and current to the device under test. In sink mode, it absorbs energy and feeds it back into the AC grid. This reduces the heat generated compared with conventional dissipative electronic loads. According to the manufacturer, efficiency at full load is 95% in source mode and 92% in sink mode.

The constant-power output characteristic allows voltage and current to adapt flexibly within the unit’s operating range. This enables a single unit to support a range of test requirements. The SM6K Series is designed for continuous full-load operation and includes overload and short-circuit protection.

Models and output ranges

The series comprises four models, each rated at 6 kW:

• SM40-CP-450: 0–40 V, up to ±450 A
• SM75-CP-250: 0–75 V, up to ±250 A
• SM330-CP-55: 0–330 V, up to ±55 A
• SM1000-CP-18: 0–1000 V, up to ±18 A

The range covers applications requiring high current as well as test tasks requiring higher DC voltages.

Control, interfaces, and system integration

The SM6K can be programmed via its front panel, integrated web interface, or Ethernet using SCPI. Optional plug-in interface modules are available for connecting the unit to test benches and automation systems.

Options include:

• Analog programming and monitoring
• Digital I/O and isolated contacts
• Serial interfaces such as RS232, RS485, RS422, and USB
• Anybus interfaces for various fieldbuses
• Master/Slave operation for parallel operation and, depending on the model, series operation

The front panel features a large display and digital encoders for adjusting voltage and current. Sequencer and arbitrary waveform capabilities support programmed sequences and dynamic test profiles. Temperature-controlled fans help keep operating noise low.

Technical specifications

• Nominal input voltage: 380–480 V AC, three-phase, 50–60 Hz
• Power factor correction (PFC): up to 0.99 at full load
• Efficiency at full load: 95% in source mode, 92% in sink mode
• Output ripple and spikes: from 1.5 mV RMS / 12 mV peak-to-peak
• Regulation deviation: from 1 mV for a 0–100% load step
• Recovery time: from 100 µs for a 50–100% load step
• Programming speed: from 0.6 ms for 10–90%
• Output voltage and current stability: 35 ppm and 40 ppm, respectively
• MTBF: 500,000 hours
• Permissible ambient operating temperature: −20 to +50 °C

These are manufacturer specifications. The selected model and configuration should be taken into account when evaluating the values for a specific application.

Dimensions and standards

The units are designed for 19-inch rack mounting and occupy 2U of rack space. They are 586 mm deep and weigh 16 kg.

The SM6K Series meets the stated emission and immunity requirements of EN 61326-1 and the safety requirements of EN 61010-1. Input and output isolation is rated at 3750 V RMS for one minute; the protection rating is IP20.