Principles Of Operation - Thermo Scientific Locator Series Operation Manual And Parts List

A L N
CCESSORY IQUID

Principles of Operation

The innovative LIQUID NITROGEN LEVEL MONITOR
from THERMOLYNE utilizes ultrasonic sound waves to
sense the level of liquid nitrogen inside a or LOCATOR
Plus cryogenic storage vessel. A microprocessor control
provides continuous indication of the liquid nitrogen level
inside the LOCATOR or LOCATOR Plus. Audible and
visual alarms also provide an early warning of low level
conditions.
ULTRASONIC sound waves sense the level of liquid
nitrogen inside the LOCATOR or LOCATOR Plus vessel.
By using ultrasonic sound waves to sense the level of liq-
uid nitrogen, no physical probe is required to sense the
level of liquid nitrogen. Conventional devices use probes
which must be in physical contact with the liquid. This
physical contact increases liquid nitrogen consumption.
There is NO increase in liquid nitrogen consumption by
using the THERMOLYNE LEVEL MONITOR.
Microprocessor Functions
5 segment LED indication of the liquid nitrogen level.
The LED display is graduated in 5 segments; Full, 3/4,
1/2, 1/4 and Empty, similar to a fuel gauge on an automo-
bile. The bright orange LED display provides quick and
reliable visual indication of the level of liquid nitrogen
inside the LOCATOR or LOCATOR Plus vessel.
Audible and Visual alarms
1. "LOW LEVEL" indicator light flashes on and off
when 2" of liquid nitrogen remains inside the
LOCATOR or LOCATOR Plus vessel. In this sit-
uation, the level of liquid nitrogen is low, and
you are alerted to re-fill the vessel as soon as
possible.
2. An AUDIBLE alarm will sound intermittently
when 1" of liquid nitrogen remains inside the
LOCATOR or LOCATOR Plus vessel. The "LOW
LEVEL" light described above will continue to
flash as well. In this situation, the liquid nitrogen
L M
ITROGEN EVEL ONITOR
O
PERATION
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