Quick answer: With output disabled, establish the DUT voltage and current limits, verify polarity and wiring, configure supported protections, then enable output while monitoring the load. The instrument’s manual takes precedence over a generic sequence.
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Before connecting the DUT
Identify the DUT’s permitted voltage, current, polarity and startup conditions. Check the supply input configuration, protective earth, ventilation and output ratings. Use connections suitable for the current and voltage; connector style alone does not establish a safe rating.
Prepare settings with output disabled
- Set a voltage appropriate for the DUT and a current ceiling suited to startup and normal operation.
- Configure OVP, OCP or other functions only if the model provides them, using its documented limits and reset behaviour.
- Verify polarity and connections while output is disabled.
- Use the model’s prescribed procedure to check settings; do not intentionally short arbitrary supply terminals to set current.
Enable output and observe
Watch the output voltage, current and CV/CC state. In CV mode the DUT draws current below the ceiling. In CC mode the supply reduces voltage to hold the selected limit. Unexpected voltage collapse, unusual temperature or a protection indication requires diagnosis before raising the limit.
Loads that need extra checks
Batteries, motors, inductive loads and equipment containing another power source can return energy to the supply. Confirm external-voltage, reverse-current and transient requirements from the exact documentation. A bench source is not automatically a battery charger, electronic load or universal laptop adapter.
Finish the test
Disable output and follow the manufacturer’s discharge procedure before removing connections. Record settings and observations if the test must be reproducible. Inspect the exterior and leads safely; use qualified service for internal faults.
Common questions
Does the current setting force that current? In CV operation it sets a ceiling; load behaviour determines current. In CC operation the supply adjusts voltage to hold the current.
Can one supply power different devices? Only when its range, control, connector, polarity and external-energy behaviour fit each device. Verify those requirements for every connection.
Practical checks
| Check | What to verify |
|---|---|
| Before wiring | Check mains input, ratings, ventilation and the DUT requirements. |
| Before output ON | Verify voltage/current limits, polarity and supported protections. |
| During operation | Observe CV/CC state and abnormal voltage, current or temperature. |
| Disconnecting | Disable output and follow the documented discharge procedure. |
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