Universal Level Sensor, Bus

Bus manufactures (including City, Tour and Luxury buses) require feedback on the status of all the fluid level containers and reservoir tanks on their vehicles, but they struggle with the different style and types of sensors required to provide that feedback.

  • Is the coolant reservoir full enough to keep the engine cool in the heat of the summer? 
  • Does the power steering fluid reservoir have enough fluid to control the vehicle safely? 
  • Are the onboard water storage tanks full enough for the next trip?
  • Are the onboard dirty water tanks too full until the next maintenance event?
  • Is there enough brake fluid to stop the vehicle safely?
  • Is there enough engine oil to properly lubricate the engine?

With all these different applications with different fluids, the manufacturer needs to buy and stock several different styles of these liquid level sensors.  Many different part numbers, in lower volume, leads to increased costs and adds to warehousing more parts than needed.

Challenge:  Finding a single liquid level sensor, with no moving parts, that will reliably detect water, oil, essential fluids, coolant as well as fuel and will endure the environment of a bus.


Traditional liquid level sensors (that can detect all fluids) rely on a float that will physically move up and down.  The sensor is calibrated to the specific gravity of the fluid.  It will operate differently in oil as compared to water.   Also, these traditional float-style sensors have moving parts.  When they are mounted in a high vibration and shock, environment, like a city bus, the floats can become damaged and malfunction.

Gems Sensors’ new Universal Level Sensor (ULS-100)

Based on Gems new universal level sensing technology, the new ULS series does not rely on the specific gravity of the fluid to detect its presence or absence.  It will reliably detect most any fluid.  Along with its robust housing and wide operating temperature range, the new ULS is perfect for all these varying fluid applications like the ones found on a City, Touring or Luxury bus.

Universal Level Sensor Features & Benefits: 

  • Durable sealed design – IPX7 & IP6k9k
  • High pressure range
  • Developed for the most rugged aqueous, oil and hydrocarbon applications
  • Tolerates coolant coating – no false triggers due to old, dried on fluid
  • Wide temperature range
  • Small size – under 3˝ (75 mm) total length.



Adjacent products:

  • XM/XT-800:  liquid level continuous sensor, fluid storage tanks
  • XM/XT-700:  liquid level continuous sensor, fluid storage tanks
  • 3100/3200:  pressure sensor, hydraulic system
  • 1100:  pressure sensor, air compressor and engine oil pressure