General PNG2000A Manuel De L'utilisateur page 5

The following table explains the meaning of all
possible combinations of visual and audible
indications.
Detected
condition
Ready to sense gas
High gas concentration:
above (50±10)% LEL
Low gas concentration:
between (20±5)% LEL
and (50±10)% LEL
Low battery charge:
<2.7VDC
Sensor fault
Change the batteries immediately upon hearing the
audible indication for Low Battery Charge in the
table. To avoid draining the batteries, reset the power
switch to OFF following each use.
All manuals and user guides at all-guides.com
Visual
indication
Green LED
flashes every
2 seconds
Red and yellow
LEDs on
Yellow LED on
None
Yellow LED on
Audible
indication
Two ascending
tones every
7 seconds
Five ascending
tones
twice/second
Two tones at
same pitch
twice/second
Three descending
tones every
30 to 75 seconds;
interval depends
on charge level
One tone every
1.5 seconds
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