VISATRON VN 215/87plus operates in a similar same way like type VN 116/87plus when it comes to a High Oil Mist alarm tripping, however, it is able to additionally indicate the suction point with the highest opacity and thus the compartment in which the overheating damage has occurred. Unlike the other types, the VN 215/87 has a single-suction-tube system, each compartment being connected by a seperate tube to valve box designed for 10 suction lines.
Measuring principal is similar to that of type VN 116/87plus. Normally, the compound opacity of the oil mist from all compartments will continuously be measured. If the seen opacity exceeds the damage check starting threshold, a damage check will be executed. lf the differential alarm level is exceeded, an alarm causing the automatic stop of the machine or a speed reduction will immediately be tripped, even if search run is not yet terminated.
By closing the valves of certain compartment groups according to an iteration procedure and by an opacity comparsion, the single-suction line can finally be determined which supplys oil mist from the compartment in which the overheating damage has occurred. For damage indication on the detector, the position of the valve which is still left open is used for indicating the damaged compartment.
In order to meet the high mechanical and electrical demands and to take account of the limited space on the engine, all VISATRON oil mist detectors are designed as packaged untits by using aluminium cast, with the wear-resistant air jet jump, the vibration-isolated base plate for the metal-clad measuring unit with plug and socket connection as well as the electrical and pneumatical connections being erected on a solid cast iron plate.
The suction tubes on left and right side are connected to the valve box by two moulded rubber flanges having no threads. The use of the particulary advantageous siphon assembly likewise allows a connection of the tubes to the siphon blocks without any threads.
All subassemblies including the valve box are provided with plug and socket connections and can, if necessary, be exchanged without the tubes at the engine needed to be dismantled.
Nor-Shipping / Norway June 04 - 07, 2013 http://messe.no/en/nor-shipping/