New Cosmos Electric KS-7D, Instruction Manual

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14. Glossary
Term Definition
Clean air or
normal air Standard atmosphere which contains 20.9 to 21.0% oxygen in dry condition or
atmosphere without target gas or interference gases.
Gas detector Device used to detect the presence of a target gas and to give its concentration in
the form of an electrical signal.
Diffusion type Sampling method using convective diffusion while placing a gas detector at a
detection point.
Target gas Specific gas to be detected, concentration displayed, and used to trigger alarms.
Detection range A range of target gas concentrations that can be displayed and trigger alarms.
Service range A range of target gas concentrations the detector is able to indicate, which are
usually outside the Detection Range and used only as reference.
Alarm set value Preset gas concentration level at which an alarm is triggered.
Alarm accuracy Difference between the alarm set value and gas concentration value at which an
alarm is actually triggered, or percentage of the difference compared to the alarm
set value.
Alarm delay Time required for an alarm to trigger after the detector is exposed to a gas
concentration level, higher or lower than the alarm set value.
Operating
temperature and
humidity ranges Ambient temperature and humidity ranges in which the gas detection and alarm
system can operate normally.
Maintenance and
inspection Tasks performed to ensure that equipment operates normally and correctly.
Self-resetting Gas alarm clearance method. When the gas concentration falls below (or above
when the alarm set value is the lower limit) the gas alarm set value after an alarm
has been signaled, relevant alarm lights, gas alarm icon and alarm relay contacts
will automatically return to their normal positions/statuses.
Manual-resetting Gas alarm clearance method. Even if the gas concentration falls below (or above
when the alarm set value is the lower limit) the gas alarm set value after an alarm
has been signaled, relevant alarm lights, gas alarm icon, and alarm relay contacts
will not automatically return to their normal positions/statuses. Manual operation
is only possible when the gas concentration is below (or above) the gas alarm set
value.
Hazardous area An area in which an explosive atmosphere is present, or may be expected to be
present, in quantities such as to require special precautions for the construction,
installation and use of electrical apparatus.
Explosive
atmosphere Mixture of air and flammable substances in the form of dust or vapor which are
within their explosive limits.
Sequentially-flash There are several LEDs inside the status indicator. In the event of a gas alarm,
one LED lights at a time and the lit LED moves from left to right.