Vartech's DC electronic load range covers two models on the same 600 W platform - the EL-600 and EL-600+ - differing only in maximum current. Both are fully programmable, covering the same four core operating modes and test features, which makes the buying decision unusually simple: work out your required current, then pick accordingly.
Four Modes, One Platform
Both units operate in Constant Current (CC), Constant Voltage (CV), Constant Resistance (CR) and Constant Power (CP) modes, spanning 9 basic mode variants (CCL, CCH, CVL, CVH, CRL, CRM, CRH, CPV, CPC) selected via a 4.3-inch backlit LCD with rotary dial and keypad. CC mode is the default choice for most power supply and charger testing (a fixed current draw regardless of voltage); CV mode is useful for simulating a fixed-voltage load; CR mode simulates a resistive load whose current varies with applied voltage; CP mode holds constant power draw as voltage changes. Rated accuracy is tight on both models - CC accuracy of ≤±(0.1% + 0.1% FS) and CV accuracy of ≤±(0.05% + 0.02% FS).
EL-600 or EL-600+ - Current Is the Only Difference
Both models share the identical 600 W, 150 V maximum platform, identical mode set, identical List mode, and identical protections. The EL-600 tops out at 60 A; the EL-600+ extends to 120 A. Since 600 W is the shared power ceiling on both, the higher current rating on the EL-600+ only becomes relevant at lower test voltages (where higher current is needed to reach the same power) - if your test load consistently operates at a voltage where 60 A already comfortably covers your required power draw, the standard EL-600 covers it with no compromise. Step up to the EL-600+ only when your actual test current requirement exceeds 60 A.
Work backward from your test current, not the wattage rating
Battery Discharge Testing
Both models include a dedicated Battery Discharge Capacity test - up to 3000 Ah, with discharge time programmable from 1 second to 100 hours. This is a distinct capability from simple CC/CV/CR/CP loading: rather than just sinking current, the instrument logs the discharge profile against time, letting you verify a battery's actual capacity against its rated Ah figure. Combined with List mode (programmable step sequences with 10 ms to 99999 s step time), this supports realistic, automated duty-cycle testing rather than a single static load point.
Protection and PC Interface
Both units carry a full protection set - OCP, OVP, OPP, OTP and reverse voltage protection - along with a dedicated Short Circuit test mode for verifying a power source's short-circuit behaviour. An RS232C interface allows PC control for automated or remote test sequences, useful when the load is part of a larger automated production or R&D test setup rather than a standalone bench instrument.
Quick Reference by Use Case
- Power supply / adapter / charger testing up to 60 A: EL-600.
- Higher-current battery pack or power supply testing (up to 120 A): EL-600+.
- Battery capacity verification against rated Ah: either model's Battery Discharge Capacity test.
- Automated / PC-controlled test sequences: List mode plus RS232C interface on either model.
CIE Instruments is an authorised distributor for the full Vartech DC electronic load range. See our general guide on DC electronic loads, or contact us to match a model to your voltage, current and test requirements.