Oil-on-Water
Monitor
Model OF-10 |
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This instrument is installed 0.5m above the water level. It automatically detects oil
films using light from an LED source and is able to provide early detection of oil leakage. This instrument is
particularly suitable for monitoring
water in breeding, purification and food processing plants. In cases where explosion protection is required, the alternative
SODL series is available..
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Due to its reflectance based measurement principle, this analyser is capable of detecting virtually all types of oil.
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High luminance, long life LED light source.
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Electrically pulse modulated light source, immune to the effects of external light (measurement is possible even under direct sun light).
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Non-contact monitoring.
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Small, compact and light weight design for ease of installation and maintenance.
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"Undetectable" signal when reflected light is so weak that oil film cannot be detected.
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Peak
hold circuit eliminates interference effects of
non-oil solids floating on the water surface as
they pass across the monitored surface (e.g. domestic
refuse). If solids become trapped on the monitored
surface, the instrument will generate an "undetectable"
alarm.
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In addition to oil film detection signal, an output is available for connection to a recorder to record oil-film generation.
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Sensor
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Transmitter
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Specifications
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| Product
Name: |
Oil-on-water alarm.
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| Model
No.: |
OF-10.
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| Measurement
Object: |
Floating oil film on water surface.
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| Measurement
Method: |
Reflectance measurement of near infra-red
rays.
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| Ambient
Temperature: |
-5~50 C.
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| Humidity:
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85%RH or less.
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| Sample
Temperature: |
No freezing, no steam generation (for samples
which generate vapours, please contact DKK-TOA
for advice).
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| Analogue
Outputs: |
4~20mA DC (max. load 600 Ohm) isolated output
or 1-5v (option).
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| Alarm
Contacts: |
Oil film present, undetectable conditions, outputs
< 125V AC 0.2A or < 30V DC 1 A (resistive
loads)
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| Power
Requirements: |
100v AC ±10% or 110v AC ±10% (optional), 50/60Hz.
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| Power
Consumption: |
Approx. 5 VA.
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| Construction:
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Rainproof (equivalent to IP65).
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| Materials
of Construction: |
ABS resin and corrosion resistance cast aluminum
(transmitter). Corrosion resistant aluminum
(sensor).
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| Weight:
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Approx 4kg (transmitter) Approx 2kg (sensor).
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| Paint
Colour: |
Silver/yellow (transmitter) Silver (sensor).
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| Installation
options: |
50A pole mounting for transmitter (optional)
dedicated hanging arm for sensor (optional).
Special custom installation assemblies available
(such as floating system), contact us with details
of your application.
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| Distance
From Water Surface: |
0.5m (±0.2m).
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| Response
Time: |
Approx 20 seconds (from oil presence to alarm
generation). |
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Principle
of Operation
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The
reflectance of an oil film is greater than that of water
(when an oil film is present on water, it has a "glistening"
effect). From this property the presence of oil can
be detected by applying a light beam of constant intensity
to the water surface and then measuring the intensity
of the reflected light.
Pulse modulated light from an LED is passed through
a collimate lens and falls onto the water surface to
be monitored. The reflected light from the water surface
is measured by the light receiver via a condenser lens.
The light receiver converts the light to an electric
signal which is amplified before passing through a narrow
band pass filter which removes the effects of external
light interferences. Only the signal component passes
to the peak hold circuit where the peak value of reflected
light is held for a fixed period. When the peak value
exceeds a preset value, the oil on water alarm is activated
and a contact switching output signal is generated.
When the reflected light drops for a period longer than
two minutes, an "undetectable" alarm is generated. The
undetectable alarm indicates instrument malfunction
or the presence of floating solids on the water surface.
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System
Overview
Special
Applications
Special
Float Application of OF-10
Close up view of sensor
Sensor
mounting arrangement in float
View
of complete float assembly
(ready for delivery to client, in our factory)
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