Hamilton VisiFerm Optical DO

Hamilton VisiFerm Optical DO

Hamilton is the first company to offer a self-contained oxygen measurement in the popular 12 mm format similar to standard process and pH electrodes and classical sterilizable oxygen sensors. VISIFERM DO optical sensors demonstrate a number of substantial advantages because of a symbiosis of sensor and measurement amplifier- an intelligent sensor.

Features and Benefits
  • suitable for steam sterilization, autoclavation and CIP
  • flow independant; self diagnostics
  • electrolyte-free so no leakages occur
  • no polarization time required
  • easily replacable sensor cap containing the sensing element
  • replacement sensor caps available
  • digital and analog (4-20 mA) signal output
  • ECS-mode available (Clark cell simulation)
  • connector heads: VP 6 and Arc (VP 8)
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Optical oxygen measurement

Combined in the VISIFERM™ sensor shaft are: high-temperature resistant optical electronics, microprocessor, 4 to 20 mA analog output, digital RS 485 interface with ModBus protocol, and ECS interface. The Electro-Chemical Sensor (ECS) interface allows VISIFERM™ DO to be connected to existing classical measurement amplifiers designed for sterilizable oxygen sensors, such as the HAMILTON OXYFERM™. Use of the 4 to 20 mA analog output or the digital RS 485 interface (both integrated into the 12 mm shaft) makes an external measurement amplifier unnecessary, allowing measurement signals to be fed directly into a process control system.

Clear favorite in comparison

HAMILTON has successfully manufactured steam-sterilizable, autoclavable, CIP-compatible sensors for pH, oxidation/reduction, conductivity, and oxygen measurement for many years. These classical oxygen sensors are based, as is common in the industry, on Clark Cell technology, in which oxygen diffuses through a membrane and is reduced electrochemically on a precious metal. The electrons involved in this process generate a very small current (nanoamperes) which is converted to an oxygen measurement signal by a measurement amplifier. Sensors such as these have served well for decades, but have their limitations.

VISIFERM™ DO optical sensors demonstrate a number of substantial advantages. This is because users of the VISIFERM™ DO receive more than just a sensor based on a new measurement principle. VISIFERM™ DO is a symbiosis of sensor and measurement amplifier—an intelligent sensor.

Application fields

VISIFERM™ DO sensors have been evaluated in a variety of applications:


VISIFERM™ DO sensors are developed to be steam sterilized and autoclaved without difficulty. CIP cleaning is also tolerated very well. These properties, along with the standard design form of a classical 12 mm sensor with PG 13.5 thread, make VISIFERM™ DO superior for use in fermenters and similar demanding applications.


VISIFERM™ DO is already being used to monitor carbon dioxide recovery, and is finding further application in the wort tank. Installations in the area of beer and beverage bottle filling are still in various test runs.

Cooling water cycles

Found in power plants and other applications for trace measurements Gas monitoring applications depend on the composition of specific samples.