Tank Automation & Monitoring Guide

Spectra has a few different available options for automated tank operation and monitoring, described below.

The Tank Full Float Switch is our most widely utilized option and is included with each Connect system. The float switch is installed at the top of the tank and will turn off the system when the tank is full and then automatically starts a freshwater flush. Depending on the install, often times the float will need to be unclipped and flipped over 180 degrees to function correctly.  Tank Full Float Switch Orientation Guide

The Tank Low Float Switch works in a similar manner. This switch is installed towards the bottom of the tank (typically about 1/3 of the way up from the bottom) and when enabled will start the system and make water once the water level drops below that of the float switch. Spectra STRONGLY ADVISES against leaving this switch enabled when away from your boat, since an unsupervised leak could be a potentially catastrophic situation for the vessel.

The Tank Level Sensor is a great tool to let you know roughly how much water you have available in your tank with a quick glance. This convenience eliminates some of the guess work so that you always know how much available freshwater you have. An important distinction to note is that this does not start or stop the system and is for informational purposes. This sensor works based on the weight of the water in the tank.



  • Tank full float switch (EL‐SWT‐LV TANK FULL SWITCH TOP MOUNT)
    1. This is installed at the top of the tank. Once the float closes the circuit for 2 minutes the tank finishes running and does a freshwater flush.
      1. On PCB the circuit connects to the TANK 1 pins
      2. At bus bar pictured below the circuit is between the green and orange pins
    2. Note: this float may need to be flipped 180 degrees on its rod to work properly. Simply remove the clip and the float flipped upside down
    3. Potential issues:
      1. If the float switch loses contact for just a split second the tank will continue to fill until there is a minute with contact.
      2. If the ship is on one heel for one minute and the tank is not completely full, yet the switch is closed, the system will start a flush.   


  • Tank low float switch (EL‐SWT‐SMLV SIDE MOUNTED FLOAT SWITCH)
    1. This is installed towards the bottom of the tank (we suggest 1/3 from the bottom). When the water level drops below the switch the circuit opens and the system makes water until the tank it full.
      1. On the PCB the connect to the TANK 2 terminals.
    2. Spectra STRONGLY ADVISES against leaving this switch enabled when away from your boat. 


    1. These are strictly for monitoring the level in your tank, they do not cause the system to start or stop.
    2. This is a pressure sensor that feels the weight of the fresh water in the tank. When it is calibrated the operator enters in how many feet or inches the waterline is above the sensor.
    3. If the bottom of the tank is not accessible people have had success installing these sensors. At the line connecting to the inlet of the ship’s pressurized freshwater pump.
      1. On PCB these connect to the pins 5V, TANK1, GND and 5V, TANK2, GND
      2. On the bus bar pictured below the red, white, and black wires are used.


Tank High Switch is enabled by default, and should be disabled in the settings menu if not being used. The Tank Low Switch and Tank Level Sensors must be enabled in the settings after they are installed.