Visatron VN301Plus

Oil mist detector for Visatron VN301 plus 2 and 4 stroke engines

Function overview:
The day- to-day mission of Schaller & Engine Protection Partner is to detect potentially harmful operating conditions in which hazardous oil mist is released as a result of bearing damage. In extreme cases, these oil mists which consist of tiny oil particles have a tendency to cause an explosion in the crankcase of the engine- Schaller oil mist detection systems represent the last reliable safeguard against such accident.

In order to respond to today’s market demands, we at Schaller & Engine Protection Partner have to put considerable thought into how we could make our product even safer and simpler.

For Schaller & Engine Protection Partner, “safety first” is not just an empty phrase or marketing slogan, it has been part and parcel of our corporate culture and practiced every day for more than 60 years. The VN301plus is based on 50 years experience in oil mist detection.

The VN301plus system consist of a central unit which up to 20 sensors (master slave version) can be connected. Each sensor monitors one crankcase compartment independently and is an standalone unit. When a sensor is replaced, the surrounding sensors ensure that the crankcase is monitors under safe conditions.

Our hybrid cable solution offers flexible installation options and, as always , offers the benefits of our technology which is based on the Venturi principle. And what’s more, there are no wear parts or time- consuming repairs. We use fresh air to keep our sensors completely clear of dirt. This reduces maintenance overheads significantly and rules out false alarms.

The no-frills display of our central unit means you quickly gain an overview of the system status. Our products are geared towards Industry 4.0 due to our CAN and Modbus interface options.

All of our Know-how and many decades of experience has gone into making this product which means we can confidently say, ONE engine; ONE VN301plus- FOR LIFE…

The sensor

The sensor consist of 3 parts

  • Engine wall screw fitting

  • Sensor

  • Hybrid cable

Flexibility, simplicity and reliability – this is how we control your operating cost more effectively! The engine wall screw fitting allows the sensor to be mounted on the engine and also the intake and return of the crankcase atmosphere.

The engine wall screw fitting with is flexible intake funnel is mounted from the outside. Its form prevents splash oil from being drawn in and a false alarm being triggered. We can offer you s suitable engine wall screw fitting to match the engine wall thickness.

Thanks to the rugged compact design of our sensor, it can easily be mounted on every engine. Our VN301plus can be attached to diesel/gas and dual- fuel engines- UNIVERSAL SOLUTION!.

Schaller has developed a sensor based on the Venturi principle that reduces spare parts and maintenance. It has been redesigned in order to also to achieve a significant reduction in air consumption. Keeping you operating cost under control.

The sensor is connected to the central unit using our hybrid cable. The cable supplies compressed air and power to the sensor and facilitates exchange of data with the central unit.   This means that our products can communicate with Modbus or CAN Bus.

Our hybrid line allows fast installation, adapts to every engine configuration and , due to its structure , protects the cable from damage due to external factors.


Easy installation of all types of engines!


The new designed hybrid cable supplying compressed, power and signals!

The central unit of the VN301plus system has the following functions:

  • Disturbing power supply to the sensors
  • Providing the operator with necessary information on system status
  • Programming and adjustment

The central unit is designs to withstand extreme conditions such as vibrations or high temperature at the engine. All important information is available at a glance.  Up to 10 sensor can be connected to the central unit , and up to 20 as master slave version.

Our new software makes it possible to calibrate the sensors so they are always perfectly adjusted to the engine operating conditions. Our tried and tested “floating zero algorithm” adapts to the opacity in the crankcase arising from the operation conditions and therefore prevents false alarms.

The Remote Indicator II can be connected as an option.

The central unit can communicate with modern control systems via ModBus or CAN bus. All data in the system is stored in the central unit for analysis.



TypeSensor VN301plus
Communication sensor- central unitRS485
DisplayGreen: Ready / Red: Alarm
InstallationG ¾ M27 x 1,5
HousingPPA + GF, halogen- free
Air pressure2,5 bar
WeightSensor: 850 g- Engine wall screw fitting: 350 g.
Operating temperature5- 70 degrees Celsius
Max. length of hybrid cable30 m
Atex classification (VN301plus)II -/2G Ex OP IS IIB T4-/ GB


Central unit 
TypeCentral unit VN301plus
Communication interfaceCANopen/ MODBUS (RE485)
Inatallation4 x M10
DisplayOil concentration- Alarm localization- Pressure setting-
System status & Installation
Voltage18- 32 VDC
CurrentMax. 3A.
Air pressureMax. 12 bar
Air pressure connection, pressure regulatorG ¼
Weight7.00 kg.
Vibration+/- 1,6 mm displacement or 4 G (5-100 Hz)
Operating temperature+5- + 70 degrees Celsius
Number of sensors10- 20 in master slave configuration
Relay output2 x Oil Mist Alarm- 1 x Ready- 1 x Pre-alarm
StorageEvents: 8000
Air humidityMax. 95%
Communication cable to sensorSchaller hybrid cable