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Fuelmon 501- User Manual

Fuelmon 501 - User Manual


The Polar Monitoring Fuelmon 501 is a remote monitoring telemetry device for fuel tanks.

It was designed to give owners an accurate and reliable fuel monitoring system. It monitors the fuel level inside of the tank and converts it to a volume.

The Fuelmon 501 controller comes with the ability to view all the data via the web portal.

Remote Monitoring

The heart of the Fuelmon range is the ability to remotely monitor these tanks using the Polar Monitoring online portal.

Polar Monitoring provides the following facilities on its web-based portal:

  • Visualizations of collected data
  • Logging & history of data points
  • SMS & Email Alerts
  • Reports & CSV Downloads

The Polar Monitoring portal is located at:  https://portal.polarmonitoring.com


You will need a valid user account in order to make use of the online portal.

Ask your subscription administrator to create an account for you. Or if you are the subscription admin you can add additional users via the “Users” Tab.

You can give multiple number of users to access the device.


Should you require any assistance please feel free to contact us.

Email: info@polarmonitoring.com

Phone: +27 82 441 9917



Fuelmon 501 Installation

Physical Installation

Mount the unit at a convenient place close to the tank. The unit is IP65 water & dust resistant, so it can be mounted outdoors.

Keep in mind that the unit uses GSM connectivity, so it should not be mounted close to any large transformers or electrical machinery as this could affect the GSM signal.

The GSM antenna needs to be mounted externally from the enclosure and cannot be placed inside any metal container as this will prevent the devices from getting signal.

Make sure that the unit is mounted vertically, with the cable glands positioned at the bottom.

Electrical Installation

  • Open the front cover
  • The wiring connections are all done on the din rail mounted terminals on the inside (bottom) of the enclosure.
  • There are larger glands for the pressure transducer cables and power and smaller glands for the water sensing probe and GSM antenna


The electrical connections are shown below:

Group Name




Wire Colour

Power In

230V AC (6A)










Level Sensor Probe

4-20mA 2 wire (12V DC)



Green /Yellow


Negative (-)



Positive (+)


Water Detection Probe

12v Water detection probe





Negative (-)



Positive (+)





Image of terminals:

There are 3 steps to correctly wiring the unit:

  1. Connecting AC power to the unit
  2. Connecting the pump run sense (optional)
  3. Connecting the sensor probe


1.     Connecting AC power to the unit

This step involves connecting power to the Fuelmon unit. This will be used to power the Fuelmon unit and its internal electronics.

NB: Please note that Fuelmon 501 controller operates on single phase 230V AC power.

Connect terminal 1, 2 and 3 up to the corresponding mains power source.

If you are taking power from a 3 phase supply, you only need to connect neutral and one of the phases.


2.     Connecting the Water sensing probe

To detect if there is water in the tank one must wire in the water detection probe.

We do this by connecting terminal 7, 8 and 9 to the correct wires on the probe.

The probe itself must sit 2-5cm off the bottom of the tank and have its cable fixed at the top of the tank.



Connecting the pressure sensor probe

Installing the sensor into the well

The pressure transducer must be placed against the bottom of the tank to provide the most accurate readings.

Secure the sensor cable tightly at the top of the tank so that the sensors height does not change. Ensure that the weight of the sensor will not cause the cable to cut or fray against the wall/edge of the well.

Connecting the pressure sensor to the controller

Bring the sensor cable through the cable gland at the bottom of the enclosure.

Ensure that the breather tube is not exposed to the elements and that moisture and or dirt cannot get into the filter.

Connect the 3 wires in the correct order to terminals 4, 5 and 6.

Ensure that the shielding of the cable is connected to the dedicated Ground terminal for the sensor.




Product Specifications



Power Input Voltage

230V AC

Power usage

12W Max


330mm (Width)

330mm (Height)

190mm (Depth)

Weight – PVC Enclosure

3 Kg

Weight – Steel Enclosure

5 Kg

IP Rating

IP65 (water & dust)

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