Gems Non-Contact Radar Level Sensor in Commercial Marine

The commercial marine market encompasses all the non-military ships.  This includes tugboats, ferry boats, cruise ships, and tanker ships to name a few.  If you’ve ever been on a ship or a large boat, you realize they have all the same systems that a house or even small town would have.  They have a propulsion system, an electrical power generation system, a potable water system, sewer system, and HVAC system.  All these life supporting systems are vital for the ship to operate correctly, including many additional systems that improve the safety and functionality of the ship.   

Many of these systems require accurate and consistent level sensing measurement.  Some of the tanks on commercial marine are listed below with their function.  

  • Ballast Level:   Ballast tanks help maintain proper lower center of gravity providing a smoother ride for the crew and passengers.   
  • Fire suppression:  Fire suppression systems like AFFF (aqueous film forming foam) system is used to smother the fire and limit oxygen from fueling the flames.  
  • Bilge Tanks:  The bilges will be the lowest level of ships and they are beneath the main engines and other voids.  Any spilled or leaking liquids like oil, fuel, and water can accumulate their and will need to be emptied routinely.   
  • Lubricating Oil Tanks:  Oil tanks including hydraulic oil, gear oil, or engine oil is stored in tanks and it’s important to keep accurate level measurements as these are vital to efficient propulsion and power systems.  
  • Fuel Tanks:  Many large ships will operate on diesel fuel which will feed both the main propulsion engines and the electrical generators.  Ensuring proper diesel fuel level is critical to not run out and be left stranded with no power or propulsion.  
  • Water Tanks:  Ships will typically have Reverse Osmosis systems that convert sea water into fresh drinking water.  The potable water is stored in tanks for domestic use like drinking, cooking, and showering.   
  • Sewage and Wastewater:  Ships need their own waste system that will hold the waste until the ship is back in port or it can be pumped overboard if they are the allowable distance away from land.   

As these tanks are used within their individual systems it’s important to monitor the level of each as they all serve an important function.  In addition, another important reason for accurate level measurement is the need to prevent overfilling the tanks.  Since this is a commercial marine application, any overfilling can cause the fluids to spill overboard, which for most of these liquids will be harmful to the environment and can result in fines and or prosecution.   

Challenge:  Finding a cost-effective, easily configurable non-contact level sensor that can handle diverse sensing range, and not be affected by the hydrocarbon vapors within oil and fuel tanks.   

 

 

Solution:  Gems Non-Contact Radar Level Sensor 

 

The Gems radar level sensor is a non-contact continuous level transmitter Radar technology works by sending out short microwave signals toward the liquid via the sensor.  The microwave signal then hits the liquid surface and bounces back toward the sensor.  The sensor utilizes the time-of-flight principle which uses the known speed of the microwave, and the time it took for the signal to return, divided by two (since it had to travel down to the liquid and then back up to the sensor) to determine the distance between the liquid level and the sensor.  Since most level is based on the height of the liquid, not the height of the non-liquid (air), the air height is subtracted from the total tank depth to determine the liquid level!   

Gems non-contact radar sensor is a great fit in the commercial marine market for several reasons.  With an Ingress Protection rating of 68, it can be installed in high moisture environments with no risk of moisture intrusion.  It is constructed of PVDF which is resistant to corrosion and is not affected from harmful UV light exposure.  With a 2” NPT mounting it has a standard mounting that will be compatible with most tanks found on commercial ships.    

A key benefit of Gems non-contact radar sensor is its ability to be configured to any tank ranging from 1 foot up to 49 feet.  This allows the ship to procure one type of level sensor and use it on all the different style tanks and tank depths they have onboard.  Previously with a float and stem-based level sensor, you would need a specific sensor for each tank depth and liquid type.  In addition, many ships have little head room above the tanks, so it can be difficult to fit a large stem and float-based sensor into the tank.  Submersible pressure sensors are another option, but you need to worry about chemical compatibility of the cable and sensor head.  These also require calibration adjustments between different oil specific gravities.  Gems’ non-contact radar level sensor does not need adjustment when used with different medias and its non-contact design eliminates the need to worry about chemical compatibility.  With a maximum process temperature rating of 80 degrees Celsius and full vacuum to 43 PSI rating, it can withstand extreme applications.   

 

Below are additional benefits of Gems Non-Contact Radar Level Sensor:    

  • Comes standard with Bluetooth configuration/setup.  This saves sourcing and inventory costs as it reduces inventory management from multiple specific transmitters for each different tank depth down to one! 
  • Compact design which helps reduce expensive shipping costs and transit times.    
  • Non-contact design means no media ever comes in contact with the Radar sensor.  This eliminates the need to worry about material compatibility between the media and sensor components. 
  • The non-contact design is by default a no moving parts solution, which eliminates the potential for any mechanical failures from a float or probe-based sensor.   
  • Radar through the air technology is a very accurate sensing technology and can detect liquid level within 5mm, with no effect on its accuracy based on changes in temperature or pressure.   
  • Radar technology is not affected by condensation or dust in the air like ultra-sonic based sensors.   

 

The above characteristics make Gems’ radar sensor an ideal solution to work in commercial marine.  With standard outputs including 4-20mA, and Modbusit is compatible with almost any type of controller or display.  Gems radar sensor also has built-in Bluetooth capability for simple configuration.  During setup it has the ability to sense obstructions within the beam angle and ignore them.  This increases the potential installation areas as there is no need to work around tank obstructions like pipes or other sensors.  This helps save countless installation man hours and eliminates the need to make costly tank modifications.       

Gems Radar Level Sensor is an excellent match for the Commercial Marine Industry.        

 

Additional Sensors: 

  • XT-800 medium float level transmitter 
  • XT-36490/66400 large float level transmitter 
  • LS-270 single point level switch with slosh shield