VICI 450 Dynacalibrator - Manual (Page 5)

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Introduction
General Description
VICI Metronics Dynacalibrators ® use Dynacal ® permeation devices to generate
the precise gas concentrations necessary for calibrating air pollution analyzers,
monitors, and other instruments that measure gas concentrations in the parts-
per-million range and lower.
Dynacalibrators are available in four models, each with a large variety of
optional features to fit a wide range of calibration require ments. All critical
factors, such as permeation rates, gas flow rates, and permeation chamber
temperatures are calibrated against standards traceable to the National Institute
of Standards and Technologies.
Model 450 specifications are listed on page 7.
Dynacal Permeation Devices
Metronics Dynacal permeation devices are the simplest and most reliable
method for supplying a source of trace quantities of various gases. They can
ac commodate virtually any requirement for generat ing low concentrations of
gases. Permeation rates from thousands of ng/min down to fractional parts of a
ng/min are possible. The devices can be supplied filled with any one of hundreds
of different compounds, both organic and in organic.
How to Use This Manual
This manual provides installa tion, operation, and maintenance information for
all configurations of the Model 450. The identification tag on the rear panel of
every Dynacalibrator is stamped with the unit’s complete model number, which
reflects the exact unit configuration. A chart on the last page of the manual
explains the model num bers.
Basic Design
The Model 450 contains two cali brated gas regulating systems – the carrier
system and the dilution system. The fixed flow carrier gas system includes
a permeation chamber containing the permeation device. The temperature
of the chamber, which controls the permeation rate of the calibration gas
from the permeation device, is set and monitored at the front panel. The
carrier stream is pumped through the chamber to pick up the calibration gas
and is then fed on to a mixing tee. The chamber temperature is adjusted
from 30°C (or 2°C above ambient, whichever is higher) to 110°C.
The dilution gas stream is pumped through an adjustable valve and a flowmeter
to the mixing tee. Front panel access to the valve and flowmeter permits the
user to accurately set the dilution stream flow rate to the mixing tee, thereby set-
ting the concentration of calibration gas at the outlet port of the calibrator.