EsiWelma
®
s.r.l.
- 1 -
E117.602_En
These instructions are to be kept with the detector
CAUTION
The installation of a gas leak detection system does not constitute a release from compliance with all regulations for
the installation and use of gas devices, for ventilation of premises and for combustion emission exhaust laid down in
the safety standards and the legal provisions in force.
Installation, periodic inspections or replacement of equipment must be carried out by qualified service technicians.
Reference standard EN50291
1.
General
When concentrations of carbon monoxide are reached that are dangerous for man in terms of the toxicity of the gas (see
Technical Specifications), ESN26.C detectors produce visual signals (by means of dedicated LEDs) and acoustic warnings (via
the built-in buzzer), and at the same time close the internal relay that controls the electrical signalling devices or activate the
solenoid valve to shut off the flow of gas.
Carbon monoxide is detected by means of an algorithm referred to as "integrated threshold" which takes into account both the
concentration of the gas and the time at which it is detected, in conformity to the requirements of European Standard EN50291.
An initial activation threshold, set at 50 ppm (= parts per million of concentration of the gas in air) starts a timer. If the
concentration continues for the time set on the timer, the alarm is launched within a time of 60 to 90 minutes. If the
concentration exceeds 100 ppm the alarm is activated within a period of 10 to 40 minutes, whereas at 300 ppm (or a higher
concentration) the alarm is immediate (within about ten seconds). For intermediate concentration values, the alarm will be
activated in proportionally intermediate times within the time range indicated above. Once the alarm condition ceases, or
below 50 ppm, for a time based on the speed of decent of the concentration, normal functioning of the detector is reinstated.
