VICI 120 Dynacalibrator - Manual (Page 3)


Introduction
Unpacking
Every Dynacalibrator ® is completely calibrated, tested, inspected, and
carefully packed prior to shipment from the VICI Metronics Inc. plant. Upon
receipt of your unit, inspect the packages for visible evidence of damage to
the shipment or its containers. Damaged shipments must remain with the
original packaging for freight company inspection
Check the packing list to make sure that the number of cartons received
tallies with the packing list. The shipment should include the following:
• Dyncalibrator Model 120
• manual
• power cord
• forceps
• permeation device holder
• power inverter for operation from a 12-volt source
Permeation devices, if ordered, will ship separately. The permeation device
shipping tubes, complete with the charcoal and desiccant packets, should
be kept for storing the devices when they are not in service. If a device will
not be used for at least a week and its total useful life is less than a year,
leave it packaged and place it in cold storage to prolong its useful lifetime.
General Description
The Dynacalibrator Model 120 is a completely portable instrument for gen-
erating precise ppm or ppb concentrations of chemical compounds in a gas
stream, using permeation devices as the trace gas source. It is designed
for use as a reference for the calibration of instruments in the field of gas
chromatography, verifying the accuracy of analytical data generated from air
pollution monitoring, industrial hygiene surveys, odor survey programs, and
tracer studies, and in other instruments that measure gas concentrations.
Since the Model 120 can be operated by its rechargeable lead-acid battery,
by the 12 volt power inverter, or by any 110 VAC power source (220 VAC
optional), it is suitable for field or laboratory use. The battery will power the
instrument for up to 24 hours of continuous use (at lower temperatures) and
can be fully charged in 12 hours.
The Model 120 contains an insulated, constant temperature permeation
chamber which holds one or more permeation devices or one diffusion vial.
(A schematic is shown in
Figure 1, on the next page.) The chamber tem-
perature, which controls the permeation or diffusion rate of the trace gas, is
set and maintained by the digital temperature controller located on the front
panel.
An internal pump generates an air stream which travels through an activat-
ed charcoal scrubber to create “zero” air for dilution. The flow of this dilution
stream is regulated by the flow control knob and indicated by the dilution
flowmeter. As the air enters the permeation chamber, it picks up and mixes
with the permeant trace gas. The output mode control valve selects the exit
route for the resulting mixture: (1) the span outlet alone, (2) the overflow
vent alone, or (3) both the span outlet and the overflow vent. Calibration
gas exiting the overflow vent is scrubbed via an external scrubber before
being recycled into the environment.