Troubleshooting
Voltage testing walk-through
Need to verify a low-voltage landscape lighting run is healthy, either at install commissioning or during a service call.
A repeatable five-point test that catches transformer issues, wire-nut failures, and voltage drop in one walk-through. 10 minutes per run.
Tools you will need
- Multimeter (AC volts)
- Headlamp
- Notebook or phone for logging
Steps
- 1
Test at the transformer (no load)
Disconnect the run. Probe the active tap. Acceptable: 12-15 V AC. Below 11.5 V means the transformer is under-supplied (utility issue) or failing internally.
- 2
Test at the transformer (under load)
Reconnect the run. Probe the same tap. Voltage should drop no more than 0.5 V under load. A larger drop means the transformer is undersized.
- 3
Test at the first fixture
Pull the lamp from the closest fixture on the run. Probe the socket. Should read within 0.5 V of the transformer secondary under load.
⚠ Match probe polarity if you're testing on a DC-converted system. - 4
Test at the last fixture
Same procedure at the farthest fixture on the run. Compare to step 3. Difference should be under 1 V on a properly-sized run.
- 5
Test at a mid-run fixture
Catches wire-nut failures and connector corrosion that wouldn't show at the endpoints. If voltage drops sharply at one mid-run fixture, that fixture's connection is failing.