Page 28 - NG-1 1150, NG-1 1500, NG-1 2000, NG-1 3000 - Stand-Alone Nitrogen Generator System Installation Manual

TYCO Nitrogen Generator Pressure Cycling for Dry Pipe and Preaction Fire Sprinkler Systems
OPERATING NOTES:
1. The nitrogen generator produces nitrogen increasing the pressure in the nitrogen supply line which increases the pressure in the fire sprinkler system.
2. When the pressure in the fire sprinkler system reaches the pressure setting of the Air Maintenance Device (AMD), the AMD closes (no longer needing supervisory gas).
3. The nitrogen generator continues to produce nitrogen increasing the pressure in the nitrogen supply line until the cut-out pressure is reached and the nitrogen generator shuts off.
4. When the pressure in the fire sprinkler system decreases (inerting process or normal operation) below the pressure of the AMD, the AMD opens (needing supervisory gas).
5. The pressure in the nitrogen supply line equalizes with the pressure in the fire sprinkler system.
6. When the pressure in the nitrogen supply line and the fire sprinkler system decreases to the cut-in pressure of the nitrogen generator,
the nitrogen generator turns on.
7. The nitrogen generator produces nitrogen increasing the pressure in the nitrogen supply line and the fire sprinkler system, repeating
the nitrogen filling cycle.
8. The nitrogen inerting "fill & purge" process requires a 3-5 psig (.2-.3 bar) range between the cut-in pressure of the nitrogen generator
and the pressure of the AMD to nitrogen inert the fire sprinkler system within 14days.
GRAPH NOTE:
The pressures reflected in the graph are representative of the operating pressures in a typical dry pipe or preaction fire sprinkler system. Actual operating pressures may vary.
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