OPW Nano Control and Measurement System

Product information

SiteSentinel® Nano™ is a control and measurement system developed by OPW to:

  • measure a volume of liquids in the tank via a magnetostrictive probe,
  • control the tank inter-shell space, e.g. by means of e.g. slotted, optical or vapour sensors

In addition, the control may cover reporting on leaks:

  • in tank sumps,
  • under fuel dispensers,
  • in piezometers around the tank field,
  • in space between double-walled fuel pipelines

The system is used at the following premises:

  • petrol stations,
  • boiler rooms,
  • small storage facilities for petroleum products
  • and where it is necessary to monitor tanks and other equipment.

It allows to collect and process information on the volume of fuel in the tank, temperature levels of stored liquids, measurement of the amount of water at the tank bottom,

OPW Nano Control and Measurement System

924B-series magnetostrictive measuring probe

  • 924B-series probes are intended to measure the height of tank filling,
  • ensures operation in dynamic conditions
  • run measurements on a wide range of liquids, including LPG and AdBlue.
OPW Nano Control and Measurement System

Leak tightness monitoring sensors

The sensor is designed to detect liquids and leaks in cooperation with the OPW system.

Depending on the type, construction and function we distinguish:

  • Slotted sensor
  • Liquid fuel level sensor
  • Sump sensor
  • Optical liquid sensor
  • Vapor sensor

SiteSentinel® Nano™

  • Accurate real-time measurement of the level of medium in the tank (1st accuracy class probe),
  • Equipped with a large colour LCD touch screen and user-friendly graphical interface
  • Provides control over up to 12 probes and 24 sensors (up to 4 probes and/or 16 sensors can be connected to the same barrier)
  • A schedule of automatic reports at daily, weekly, monthly or annual frequency can be programmed.
  • A set of the generated reports include: Current Tank Status, History of Supplies, Ongoing Events, History of Events, Tank Leakage Tests
  • Mobile access (GSM network, Internet) enables remote station management and service (inventory monitoring, supplies, emergencies, leaks, training sessions, setups)
  • Its NANO controller, as standard, is equipped with TCP/IP communication options. In practical terms, it means that the system can be accessed (to a varying extent) locally from a PC, a personnel/driver’s mobile phone or remotely from a PC, a mobile phone. Sensitive information on leaks, alarms, supplies can be sent by SMS/e-mail.

924B-series probe

  • It guarantees full stock monitoring and leak tightness control over single and double-walled tanks.
  • Such probes (924B meters) are made of 100% stainless steel, which ensures their compatibility with a wide range of conventional and unconventional fuels and other liquids.
  • In fuel tanks, 924B probes – apart from fuel level – also measure water level, temperature and density.
  • The probe manufacturer (OPW FMS) is given the status of an accredited measuring laboratory and all its calibration certificates issued are recognised by Central Office of Measures (pol. Główny Urząd Miar, GUM) and other national metrological institutions. Thus, when buying CGH tanks, customers always find their legalisation easier and cheaper.
  • These probes, characterised by the 1st Class of accuracy, can detect leaks within single- and double-walled tanks with an accuracy of 0.378 litre/h

The “multidrop" option is available, which lets the console to connect several probes and sensors via one cable.

Technical details


  • Alarm signalling: audible, visual, possible external signalling (relay),
  • The design of its intrinsically safe inner barrier enables several units to be connected to the same EX channel.
  • This system runs with a static or dynamic (DHCP) IP address in the network.

Liquid quantity probe:

  • Technology: Magnetostrictive, with float indicators
  • Material: stainless steel
  • Working place: Zone Ex, Category: Class 1, Division 1, Group D
  • Temperature measurement: 5 independent thermistors along the entire gauge
  • Temperature working range: -40ºC ~ +60º C
  • Maximum cable length:
    300 m for Belden 88760 cable
    150 m for Belden 88761 cable
  • Maximum probe length: 605 cm

Leak tightness monitoring sensor:

  • Operating temperature range: -20°C ~ +50°C (4°F ~ 122°F)
  • If there is a break within the connection cable, an alarm will be triggered in the system.
  • Wiring: gas- and oil-resistant cable
  • Dimensions depend on the selected sensor model.