Utilizing a multimeter provides a reliable method for checking the polarity of solar energy systems. If you connect the positive and negative terminals incorrectly, you'll face reduced efficiency, potential equipment damage, or even safety hazards. Observe polarity indications on the wiring, 4. First, you must turn off the power going into your DC circuit breaker box. But fear not – today we'll turn you into a solar Sherlock, complete with multimeter magnifying glass and MC4 connector clue Ever tried assembling a DIY solar array only to realize your. The article explains how to determine the positive and negative terminals of a solar panel, crucial for proper installation to avoid energy wastage.