Electronic Loads

The flip side of a Power Supply: a load draws a programmed current (or constant power, resistance, voltage) so you can characterize a source under realistic conditions. Pair with Multimeters, Oscilloscopes for transient response, and Battery Testers for cell-level work. For verifying a board's power tree against the schematic see Circuit Simulation and PCB / EDA Suites.

Bench programmable DC loads

• ★ Rigol DL3021A / DL3031A — 200 W / 350 W single-channel DC loads with CC/CV/CR/CP modes, transient sequences, and full SCPI. ~$700–$1100. The default hobbyist bench DC load in 2026.
• Siglent SDL1020X / SDL1030X-E — Siglent's 200 W / 300 W answer to DL3021A; fast transients, dynamic mode, LXI/USB. Comparable bench-class.
• Itech IT8500 / IT8800 / IT8900 — wide range from 150 W single-channel to multi-kW racks; popular in EE labs. Used IT8511 are a common eBay find.
• Maynuo M9712 / M9711 — Chinese mid-tier; cheaper, capable, less polished GUI than Rigol/Siglent.
• Atten ATL-204D — basic DC load; not great, included for completeness.
• B&K Precision 8500 series — solid US-brand bench loads; often found in calibration shops.

Cheap / battery-focused loads

• ★ ZKE Tech EBC-A20 / EBC-A40L / EBD-A20H — ~$150–$400 USB-controlled battery testers / DC loads up to 40 A. The hobby standard for 18650 capacity testing. Closed Windows software (EBTester) plus FOSS Python lib ebsoftware.
• FNIRSI FNL-200 / KFB-300W — sub-$100 mini DC loads; OK for slow tests, not for transient work.
• Tomometer / TBC battery loads — Chinese marketplace battery testers; YMMV.

DIY / OSS

• re:load Pro (Arachnid Labs) — an open-hardware adjustable constant-current load (40 W); discontinued but designs are public.
• EEZ Bench Box has a load module on the roadmap — see OSS Bench Instruments.
• TEC-controlled MOSFET loads — many Hackaday / GitHub projects in the 50–200 W range.

High-power / specialty

• Itech IT-M3900 / IT8900 racks — kW-class regenerative loads (push power back to mains). Industrial.
• Chroma 63600 / 63800 series — multi-channel modular loads for production test.
• Magna-Power TSD — kW-class for solar / EV work.
• AC electronic loads (Itech IT7800, Chroma 63800) — for testing inverters / power supplies under non-DC conditions.

License / pricing notes

• Rigol / Siglent / Itech all speak SCPI — drive from pyvisa or lxi-tools (see Instrument Software). Vendor GUIs are free.
• ZKE EBC uses a USB-serial protocol; FOSS Python clients exist on GitHub.
• Datasheet limits matter: a "200 W" load is usually 200 W only within a derating envelope (current-limited above some voltage, voltage-limited below some current). Read the SOA chart before trusting headline numbers.
• Watch for dynamic mode bandwidth — a load that only does steady-state isn't useful for testing PSU transient response.

Pick this if…

• Default hobby bench DC load, 2026: Rigol DL3021A or Siglent SDL1020X.
• Battery capacity testing on a budget: ZKE EBC-A20.
• Used eBay bargain: Itech IT8511 or B&K 8500.
• kW-class production: Itech IT-M3900 or Chroma 63600.
• You only need <50 W and dirt cheap: FNIRSI FNL-200 or a re:load Pro clone.
• Want full FOSS control surface: Rigol DL3021A driven from pyvisa.