Sensor Cable; Bx-Pdwf Sensor - Omntec OEL8000II Installation Manual

discriminate between water and hydrocarbons. An un-alarmed condition exists in
a dry environment where light is reflected back to the photo-sensor. The presence
of hydrocarbons will cause the optics sensor to initiate an alarm. The presence of
water will cause the conductance sensor to initiate an alarm.
♦ Float – Sensor containing a device whose specific gravity is compatible with the
liquid being monitored. It will float on the liquid and rise as the level increases.
Floats can be configured to be normally closed (un-alarmed) in a dry environment
and create an open circuit (alarmed) when liquid is present. They can also be
configured to be normally open (un-alarmed) in liquid and initiate an alarm when
the float drops creating a closed circuit.
♦ Temperature – Sensor containing a thermistor to measure temperature.
Temperature sensors can be configured to alarm at high and low temperatures.
They can also be programmed as relay activator sources. Two additional set
points can also be used for temperature control (thermostat) relay activator source.
♦ Vapor Sensor – Sensor containing an adsistor to sense the presence of
hydrocarbon vapor in a dry environment. The presence of hydrocarbon vapor
causes the adsistor to increase in resistance creating a vapor detected alarm.
Sensor can be configured as a relay activator source.
2.4.1
Select sensor cable with the following specifications:
♦ Must use #22 gauge shielded 4 conductor twisted with a drain, (Belden #9940 or
equivalent). Do not exceed 2,000 feet. You can use part number EC-4 (4-wire plus
drain)
♦ PVC jacketed UL-18830
2.4.2
The BX-PDWF (see Figure 2-5) detects liquids and is used in double-wall fiberglass
tanks with dry interstitial space. It combines optical and conductance sensing
enabling it to discriminate between water and hydrocarbons.
Installation Manual

Sensor Cable

BX-PDWF Sensor

OEL8000II
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