SST GT814, Руководство по конструкции

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814-8 September, 2015
MODEL GT814 NOVA-Sensor ELITE™ Toxic Gas Detector
ROUTINE OPERATION OF THE NOVA‑Sensor ELITE
The NOVA-Sensor ELITE is designed to provide protection of personnel and property from
gas leaks 24 hours a day, 7 days a week with no regular intervention required.
Protection Mode
This is the normal operating mode, and the NOVA-Sensor ELITE will be in this mode when
all conditions are normal. The lighted blue background on the display screen will be dimmed
to conserve power, but the digital display of the actual concentration of the target gas will be
readable, even if the detector is located outdoors in bright sunlight. The green POWER indi-
cator will be illuminated, and will occasionally blink as a confirmation that the microprocessor
is continuing to check the area for gas.
In protection mode, all relay contacts are in the normal, non-alarm and non-fault condition,
and the detector will transmit a 4.0 mA signal to any connected external equipment.
Activate the ▲MagPoint▲ on thetop side of the enclosure to:

Restore the screen illumination to full brightness

Display the gas concentration that will activate the LOW ALARM

Display the gas concentration that will activate the HIGH ALARM

The detector will then return to normal operation.
Low Gas Alarm Mode
When gas is starting to accumulate in the protected area, the following occur:

The present gas concentration is displayed (The screen will remain at half brightness
during this time)

The 4-20 mA signal to external equipment increases to report the present gas con-
centration

When gas concentration reaches the low alarm set point, the SCREEN FLASHES
and the red LOW ALARM indicator also flashes.

The low alarm relay is activated
!
A typical application might use this low alarm relay contact to activate an
exhaust fan to try to remove the leaking gas from this location.

If gas concentration goes down below the low alarm set point, the red alarm indicator
is extinguished and the screen stops flashing, but remains at full brightness until the
gas concentration returns to zero.
!
If the red alarm indicator and the screen do not stop flashing when the
gas concentration is below the low alarm set point, the detector has been
configured with a latching low alarm. In that case, you must activate the
▲MagPoint▲ on the top side of the detector to cancel the low alarm and
return the detector to the protection mode. The low alarm may also be can-
celed from a remote location if the reset function has been installed in your
detector..

At zero gas concentration, the screen returns to half brightness and the detector
returns to normal protection operation.