Thermo Scientific LevelPRO, User Manual

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Product Overview
Function
Function
Source A Cesium (Cs-137) radioisotope source is used for most applications, and a Cobalt
(Co-60) source is available for applications requiring a higher energy source. The
radioisotope is bound in ceramic pellets and doubly encapsulated in a pair of sealed
stainless steel containers. The resulting source capsule is highly resistant to vibration
and mechanical shock.
The source capsule is further enclosed in the source head, a lead-filled, welded steel
housing. A shaped opening in the lead shielding directs the gamma radiation beam
through the process material towards the detector. Outside of the beam path, the
energy escaping the source head is very low and well within prescribed limits. Closing
the source shutter allows the beam to be turned off (the shutter blocks the radiation)
during installation or servicing of the detector. All source housings meet or exceed the
safety requirements of the U.S. Nuclear Regulatory Commission (NRC) and
Agreement State regulations. Refer to the gamma radiation safety guide (P/N 717904).
Detector-
Transmitter
The transmitter function in the LevelPRO system is incorporated into the detector
housing to create an integrated system, while in the LevelPRO-T system the
transmitter is a separate enclosure.
The LevelPRO measurement system uses a PVT scintillation detector to measure the
radiation reaching the detector from the source. The detector consists of a PVT
scintillator and a photomultiplier tube with the associated electronics. When gamma
radiation strikes the scintillation material, small flashes of light are emitted. As the level
of the process material increases, more gamma radiation is attenuated by the process
material, which allows fewer gamma rays to reach the detector and generates fewer
light pulses. The photomultiplier tube and associated detector electronics convert the
light pulses into electrical pulses that are processed by electronics in the detector of the
integrated unit or transmitter of the remote unit to determine the process material level
and related measurement values.
Communications &
Measurement
Display
Communication with the detector is via the RS485 and RS232 serial ports, USB, or
Ethernet from a PC running EZ Cal II software. Once the detector is set up, the
primary measurement (level) can be viewed on the display and on the EZ Cal II
software.
Display Background The display on the LevelPRO units provides measurement data to the user.
Figure 1-2.
Measurement Data Display
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2 LevelPRO User Manual Thermo Scientific