ABOUT CALIBRATION
Every gas monitoring system needs to be calibrated [except
the Delphian infrared
Determinator does not require span calibration (zero point adjustments
are required infrequently)]. Each gas monitoring channel is calibrated
separately.
HOW OFTEN DOES A GAS MONITORING SYSTEM NEED TO BE CALIBRATED?
Although some companies calibrate their systems only twice a year, we
recommend that the system calibration (for all sensors except infrared) be
checked at least every 90 days. Checking it every 30 days would be
considerably safer. Our system can detect many fail conditions, but
not every fail condition. For instance, if a sensor has become
poisoned or access
to it has been
blocked, it may lose some or all of its sensitivity. Calibration is
the only way to detect this condition. In addition, as sensors age, they
begin to lose their calibration more quickly. Sensors older than one year
need more frequent calibration to maintain their accuracy and to prevent
false alarms. Calibration is also necessary whenever a sensor is replaced.
Initial Calibration:
An initial calibration can be made within 30 minutes after system power is
applied to the sensor. However, to achieve accuracy, a second calibration
should be made no sooner than 24 hours after systems power is applied.
WHAT IS REQUIRED FOR
CALIBRATION?
Calibration gases : Zero air and Span Gas
Calibration gas regulator & sensor connector assembly
and
for the
Fuel Guard
and SafeCAL a magnetic
Calibrator
for the Sage Series III a walkie talkie
for the Remote Calibration System, a remote calibration meter
for a Micro Controller System without Remote Calibration - a
TWO TYPES OF CALIBRATION:
FLOW and STATIC
A calibration system must be chosen for each gas to be
monitored. Some gases can be calibrated by a flow method;others are
considered too dangerous to use this method and a static system is
provided for them. There is only one choice per gas. |
FLOW
CALIBRATION KITS for
Combustible
Gases
The kits which supply gas by flowing it over the sensor are of two
types.
Type A includes everything (a sensor gas connector
with tubing, a pressure and flow regulator assembly, a calibration
adapter, and a calibration screwdriver), except the gas
bottle, needed to calibrate a sensor and comes in a
carrying case which can hold one or two bottles of cal. gas.
Type B does not include the carrying case. In each
instance, A or B, the appropriate gas must be ordered with the Kit.
These gases are offered in 3.6 cubic foot canisters.
Which gas to choose for combustible gas calibration |
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STATIC
CALIBRATION KITS for
Toxic Cases
Static calibration systems come in one kit form, Type C,
which includes a Calibration Chamber, a gas calibration gauge and
valve assembly, a calibration screwdriver, and a calibration
adapter. You must select the gas to be used separately. These gas
canisters are 36 liters and provide approximately 400 calibrations.
If there is a background gas, a canister of
zero air
and a calibration kit should be selected so that a true zero
calibration can occur. This is especially important for toxic gases
such as hydrogen sulfide where a large background can exist without
the calibrator’s knowledge. |
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Sensor
Technology |
Glossary
of Gas Detection Terms
Copyright ©2023 Delphian Corporation, 220 Pegasus Avenue, Northvale, N.J., U.S.A.
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