Page 43 - NG-1 100, NG-1 250, NG-1 500 - Wall-Mounted Nitrogen Generator System Installation Manual

Commissioning
COMMISSIONING PROCEDURE
Safety Warning
Commissioning of nitrogen generator is to be performed by qualified personnel. Prior to any system commissioning on the nitrogen generator, ensure that the nitrogen generator is isolated from all system risers. Failure to do so can result in system damage and/or personal injury.
Nitrogen Generator Pressure Settings
Prior to setting the cut-in and cut-out pressures of the nitrogen generator, identify the following sprinkler system pressures:
1. Sprinkler system operating pressure/Air Maintenance Device (AMD) pressure.
NOTE: When the nitrogen generator is connected to multiple dry pipe and preaction systems,
the fire sprinkler systems must operate at the same supervisory gas pressure.
2. Sprinkler system low air alarm pressure.
3. Sprinkler system trip pressure.
Once the sprinkler system pressures have been identified, determine the cut-in and cut-out pressures of the nitrogen generator.
1. The nitrogen generator cut-in pressure is to be 3-5 psig (.2-.3 bar) below the operating/AMD pressure of the sprinkler system(s).
2. The nitrogen generator cut-in pressure needs to be 3-5 psig (.2-.3 bar) above the low air alarm pressure of the sprinkler system(s).
3. The nitrogen generator cut-out pressure is preset from the factory at 85 psig (5.9 bar) which should be adequate for most applications. Should a higher cut-out pressure be needed, adjust the cut-out pressure using the cut-out pressure adjustment procedure.
Sprinkler System Air Maintenance Device (AMD) Pressure
The proper operation of the nitrogen generator and the dry pipe nitrogen inerting (DPNI) process is dependent on the sprinkler system’s air maintenance device (AMD) pressure setting. Sprinkler system AMD pressure settings less than 3 psig (.2 bar) above the nitrogen generator cut-in pressure or greater than 5 psig (.3 bar) above the nitrogen generator cut-in pressure will have an adverse effect on the service life of the nitrogen generator.
Verify the AMD pressure setting using the Air Maintenance Device (AMD) Pressure Adjustment Procedure in the Maintenance Section of this manual.
TFP1273 Page 42 of 80