2 DG-1 SATEL
fixing screw hole.
pins for enabling/disabling sound signaling (jumper installed – signaling enabled; jumper
removed – signaling disabled).
Detecting dangerous gas concentrations
The detector will alarm when it senses a dangerous gas concentration. For information about
the gas concentrations that trigger an alarm, please refer to Table 1. The alarm is signaled by
sound and by LED indicator (repeating sequence: sound/LED ON for 1 second followed by
1-second pause, etc.). When the alarm is being signaled, the alarm output is active (relay
contacts are open). The detector will stop alarming when the gas concentration drops below
the dangerous level. The gas sensor reaction to a decrease in the dangerous gas
concentration is delayed, hence the alarm signaling can stop even a few minutes after
the gas concentration has dropped below the alarm level.
DG-1 CO DG-1 LPG DG-1 ME DG-1 TCM
Gas
concentration to
trigger alarm
50 ppm for 75 minutes
100 ppm for 25 minutes
300 ppm for 1 minute
20% lower explosive limit 6000 ppm CHCl
3
Gas
concentration to
trigger prealarm
- 10% lower explosive limit -
Table 1.
The DG-1 LPG and DG-1 ME detectors signal prealarm. For information about the gas
concentrations that trigger a prealarm, please refer to Table 1. Prealarm is signaled by sound
and by LED indicator (repeating sequence: sound/LED ON for 0.25 second followed by
1-second pause, etc.). Prealarm does not affect the state of alarm output. The detector keeps
signaling prealarm as long as the methane/propane-butane concentration remains above the
10% and below the 20% lower explosive limit.
Supervision of gas sensor and supply voltage
The detector will report trouble in the event of sensor defect (not applicable to DG-1 CO) or
when the supply voltage drops below 9 V (±5%) for longer than 2 seconds. Troubles are
signaled by sound and by LED indicator (repeating sequence: sound/LED ON for 0.25
second followed by a 0.25 second pause, etc.). When the alarm is being signaled, the alarm
output is active (relay contacts are open).
3. Installation and commissioning
Disconnect power before making any electrical connections.
The DG-1 digital gas detectors are designed for indoor installation.
Considering specific character of the gases to be detected, the DG-1 TCM and
DG-1 LPG detectors should be mounted in low position, just above the floor,
the DG-1 ME detector in high position, just under the ceiling, and DG-1 CO
detector at a height of about 1.5 meter.
1. Open the detector enclosure (Fig. 2).
