Level Instruments

Level instruments split into two families that answer different questions. A point-level switch answers yes-or-no at one height, is the tank full, is it empty, is it above the alarm point, and trips a contact accordingly. A continuous level instrument instead tracks the level across the full range of the tank and outputs a proportional signal, so the control system always knows exactly how full the vessel is, not just whether it's crossed a line.

NLS sources both families across several technologies. Float switches and vibrating fork switches cover point-level duty, the float rises and falls with liquid level to trip a reed switch, while the vibrating fork stops oscillating when submerged, a simple and reliable principle for high or low alarm points. For continuous measurement, ultrasonic level instruments send a sound pulse down to the surface and time its return, a non-contact method suited to most liquids, while radar (including guided wave radar) uses a microwave pulse instead, which holds up better than ultrasonic in the presence of vapor, foam, or turbulence. Where a level switch functions as part of a safety instrumented system, particularly overfill protection on an atmospheric storage tank, IEC 61508 is the general functional-safety reference for the SIL rating of that loop, and API 2350 sets the industry practice for overfill prevention on atmospheric petroleum storage tanks.

On Saudi projects, level instruments show up on water storage and fire water tank level control, fuel and chemical storage tank monitoring, process vessel level for batching and blending operations, and hospital and utility water tank high/low alarms where an unattended tank still needs to be protected against overflow or running dry.

NLS quotes level instruments against the tank or vessel type, level range, mounting (top-entry, side-entry), output signal, and any SIL requirement, and returns a priced quote in USD. Standard float and vibrating fork switches in common process connections typically source fastest; radar transmitters and SIL-certified safety instruments are more often built to order and carry a manufacturer-confirmed lead time.