Honeywell Midas, User Manual

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Midas
®
Gas Detector
B8-
General Notes:
1
Midas ® detectors are not ETL approved for monitoring in or sampling from classified
areas above %25 LEL.
2
End-of-line particulate filter (780248) MUST be removed when pyrolyzer unit is
calibrated/bump tested with recommended gases other than target gases.
3
The pyrolyzer unit requires a longer warmup time and a humidifier must be added
in the sample line when a dry calibration gas is applied to the detector directly from a
target gas cylinder:
NF
3
30 min
C
4
F
6
60 min
CH
3
F
CH
2
F
2
C
R134a
5
F
8
4
Recommended to keep the sample lines as short as possible where the RH condition
at the sample point is high (above %50 RH); there will be some sample loss due to
absorption onto the sample line.
5
When calibrating or bump testing NF
3
sensor cartridges with Cl
2
or HF, the charcoal
Freon filter (0027-1830) MUST be removed for calibration/bump testing then reinstalled
for monitoring.
6
Freon filter 0027-1830 is required for this application.
7
The most common failure in catalytic sensors is performance degradation caused by
exposure to certain poisons’ (referred to as Catalytic Poisons). It is therefore essential that
any catalytic based gas monitoring system should checked regularly via bump tested (or
re-calibrated), more importantly after any gas release notification when there is a potential
poisoning based gases may be present. For further details contact Honeywell Analytics
(please ensure all gases that are potentially present in the area of detection are available
prior to contacting)
8
MIDAS-E-LEL cartridge carries the standard 2 year warranty but can be calibrated to
extend its life to 5 years. For the 2 year cartridges, Honeywell Analytics allows for a period
of up to 6 months after the manufactured date for cartridge installation and then 2 years
of use. If, for example, the cartridge is installed within the first 6 months, the expiration
date will be 2 years after the installation date. If, however, the cartridge is installed more
than 6 months after the manufactured date, it will expire 2.5 years after the manufactured
date. Contact your local Honeywell Analytics Service Representative for more information.
9
An ozone generator can be used instead of 1 ppm NO
2
.
10
Contact the local Honeywell Analytics service representative for more information.
Bump Testing Notes:
1. Use a concentration of 2 ppm.
IMPORTANT: this should only be done once to avoid the danger of poisoning the sensor.
2. The ambient Oxygen level is typically %20.9 by volume. If there is a serious
problem with an Oxygen sensor, the reading will not be %20.9. The flow rate is
regulated by the Midas
®
unit.
CO
2
test gases must be in a balance of air, not Nitrogen.
As an alternative, the actual target gas can always be used instead of a cross-sensitive
gas.
Higher concentrations than the recommended ones can be used if necessary, but extra
time may be needed for the reading to recover to zero.
IMPORTANT: Do not exceed the recommended concentrations or application times
where Hydrogen Sulfide is used to test Silane. Doing this can damage the cell.