How is DP level measurement configured for a closed pressurized tank?

For closed tank DP level measurement, the high-pressure port connects to tank bottom (process pressure + hydrostatic head), and low-pressure port connects to tank top (process pressure only). The differential equals hydrostatic head (h x density x g), independent of process pressure. For elevated or suppressed ranges, configure transmitter LRV/URV accordingly. Wet leg (filled reference leg) or electronic remote seals maintain consistent low-side reference in applications with condensable vapors.