PortaSens
III
Portable Gas Leak Detector, Model D16
Operation and Maintenance Manual
Rev-A Feb 2018
- 25 -
The following descriptions apply to the default settings.
Danger Alarm
Toxic gas sensors
: Danger is normally a “high-high” alarm, set
approximately 2-3 times higher than the Warning level, and becomes active
at, or above, this level.
Oxygen sensors
: Alarm is normally a “low-low” alarm, and its level is set
to 16% O
2,
and the alarm becomes active at, or below, this level.
Warning Alarm
Toxic gas sensors
: Warning is normally a “high” (rising) alarm and its
level is set to the TLV (threshold limit value) of the gas. The alarm becomes
active when the gas concentration reading is
at or above
this level.
Oxygen sensors:
Warning is normally a “low” (falling) alarm and its level
is set to 19.5%. The alarm becomes active when the gas concentration
reading is
at or below
this level.
Caution Alarm
Toxic gas sensors:
Caution is normally a low (falling) alarm, and its level
is set to -10% of the full scale range. This is intended to indicate
excessive
negative sensor drift, a condition which should be corrected by zeroing. The
alarm becomes active when the gas concentration reading is
at or below
this
level for 2 seconds.
Oxygen sensors
: Caution is normally a high (rising) alarm and the level is
set to 23% O
2
. It is intended to indicate an uncommon condition that should
be corrected, if it persists. Note that it is normal for an O
2
sensor to produce
a high reading when left, “off bias” (unpowered), for more than a few
minutes.