When performing a loaded voltage output test, voltage should be about how much above open circuit voltage?

• A. 500 mV above open circuit voltage
• B. 50 mV below open circuit voltage
• C. Equal to open circuit voltage
• D. 1 V above open circuit voltage

Answer: (A)

When you test voltage under load, you’re checking how the source behaves when current is drawn from it. The open-circuit voltage is what you read with no load. Once a load is applied, there are resistances in the source, wiring, and connections that cause a voltage drop. To ensure the device at the test point still sees the correct voltage, the test procedure targets the source delivering about half a volt more than the open-circuit value. That small headroom compensates those drops so the loaded voltage stays within the intended range. A difference of around 0.5 V is large enough to cover typical wiring and contact losses but not so large as to risk over-voltage. Smaller differences wouldn’t reliably compensate for losses, an exact match to open-circuit wouldn’t account for the drop under load, and a full volt above would unnecessarily push the source beyond what’s needed.