RelaDyne LubriMist IVT, Инструкция по установке и эксплуатации

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LubriMist ® Model IVT
Oil Mist Generating System
Installation and Operating Manual
Page 70
of 256
Mist Density Sensor
Operation
It is important to recognize that although any given output reading may correspond to a
quantitative oil/air ratio, the oil mist sensor does not make a quantitative mass measurement of
the amount of oil in the mist. The output signal range of 0-100% represents the ability of a light
beam to penetrate the oil mist as it passes between a light source and a light detector. A mist
density reading of ZERO indicates that no or very little mist is present; the light has easily
reached the detector. As the oil/air ratio increases, the oil mist particles block the light from the
detector causing a change in the mist density reading. When light can no longer penetrate
through the oil mist particles and reach the light sensor, the monitor reads 100%.
The mist density sensor detects and responds to changes in oil/air ratio. However, variations in oil
type, grade, viscosity, and regulated air supply pressure to the mist generating head all influence
the size of the mist particle created by the generator. This also affects the instrument reading.
Other factors that effect particle size distribution and the mist density reading are oil temperature,
air temperature and oil level.
Before making adjustments, the IVT Oil Mist Generator should be in service and operating
normally for a minimum of one hour prior to making sensitivity adjustments or changes in alarm
set points. This period allows the oil output to stabilize and the mist sensor internal surfaces to
become wetted with oil.
Since the mist sensor does not measure the absolute quantity of oil in the mist, it is
recommended that a “consumption test” be made if you are striving to achieve a specific oil/air
ratio. The manufacturer recommends that the air oil ratio be adjusted to achieve an oil/air ratio of
0.65 cubic inches of oil / hour / SCFM airflow. For information regarding calibration services,
contact Lubrications Systems Company.
Location Of The Mist Density Sensor
The mist density is located on top of the bulk oil reservoir. See the product description for the mist
density sensor.
Sensitivity Adjustments
The mist density monitor is equipped with a user selectable sensitivity adjustment. This feature
allows the instrument to adapt to a diverse range of lubricating oils and over a broad range of
oil/air ratios. To access the sensitivity adjustment feature, remove the screw-on cover to the
electrical enclosure of the sensor unit. Located adjacent to the wire terminals in the detector is a
series of electronic dipswitches. Separate switches are provided for 1) low 2) medium and 3) high
mist density settings. All units are shipped with the mid sensitivity switch (#2) in the “ON” position.
Note the switch #4 interrupts power to the LED light array and should always remain in the ON
position.
After the IVT Oil Mist Generator has been commissioned and is operational, select a sensitivity
setting to obtain a mist density reading of near 50%. Once the desired sensitivity setting has been
selected, the IVT controller monitors adjustments or changes in the mist density.