Magnetic Trap Suppression Tank Level Sensor

A fire suppressant storage device (20) comprising:

• a tank (22) having a first port (40), a second port (70), and an interior (32) for storing fire suppressant;
• a discharge assembly (46) mounted to the first port and comprising:
• a discharge valve (48);
• and
• a discharge conduit (50) at least partially within the interior and having:
• an interior;
• and
• an exterior;
• and
• a liquid level measurement assembly (400) mounted to the second port and comprising:
• a tube (100) at least partially within the interior and having:
• an interior sealed relative to the surrounding tank interior;
• and
• an exterior;
• a float (120) surrounding the tube;
• and
• a member (424) axially moveable within the tube interior,
• wherein:
• the liquid level measurement assembly comprises a longitudinal array of magnetic field sensors or magnetic switches (402) within the tube;
• the member has an aperture surrounding the array;
• and
• the member has one or more magnets positioned to magnetically cooperate with one or more of the sensors for determining a position of the member along the array and with the float to relatively axially trap the member to the float.