FPS-10000, FPS-16500, and FPS-22500 Operation & Alarms – South-Tek Systems

Applies to: South-Tek Systems N2-BLAST® FPS-10000, FPS-16500 and FPS-22500 fire protection nitrogen generators.
Filter kits and the filter change procedure are in Preventive Maintenance.

How these generators behave in normal service, how to read the touchscreen, what each alarm means and what reaches the fire alarm panel, and how to trace a leak.

Normal operation

The generator cycles automatically on nitrogen storage tank pressure. It runs and produces nitrogen into the tank; at the cut-out pressure — 100 PSIG on these models — it finishes its cycle and drops into Standby; when the tank falls to the cut-in pressure it resumes. That cycling is normal — the machine only runs to replace the nitrogen the sprinkler system has actually used. A generator that never reaches Standby cannot keep up — suspect a leak or a feed-air problem.

The cut-in and cut-out pressures are factory set; contact South-Tek before changing either, and confirm your unit's values against its factory settings label.

Reading the touchscreen

The operation screen shows the whole system, not just the generator. Each piece of equipment carries a status icon — a check mark when it is working correctly, a warning symbol when it has an issue. Animated blips travel along the pipe paths to show gas moving: blue for air, green for nitrogen. Grey piping with no animation means no gas is moving on that path. The active alarm is named in the status bar in the upper right corner, and after the first alarm screen appears the display times out back to the operation screen. The red bell icon silences an alarm's buzzer for the set mute time; it does not clear the alarm.

Hold the Start/Stop button for about 1 second to change state. The indicator shows Hold for that second, then changes between Off and Running. The dashboard shows tank pressure on a large gauge, an hour meter for total run hours, and nitrogen leakage averages in SCFH for the last measurement, the current day and the current month.

Alarms — what each one means

Alarm	What it means and what to do	Reaches the panel
Bypass	The generator has handed the sprinkler system over to the air compressor — either during the 30-minute fill test, or because the generator is not keeping up. While the system is on bypass the riser is on compressed air and corrosion protection is suspended. It returns to nitrogen on its own when demand falls. If it stays in bypass, treat it as a generator fault and investigate.	Its own bypass alarm relay
BlastOff®	A possible leak, or nitrogen being overdrawn. The status bar flashes BlastOff. Inspect and test the system for leaks and component failures. Once the cause is resolved, power cycle the generator to clear the alarm — a power cycle stops nitrogen production, so it is an impairment: notify the building owner or their impairment coordinator and the alarm monitoring company, tag the system, and before you leave confirm the unit is back in Run or Standby, the panel clear and the riser at the supervisory pressure you recorded. Do not power cycle repeatedly without finding the cause.	Common alarm
Nitrogen pressure	Tank pressure has fallen below its alarm point. Check for leaks and confirm the feed air supply is available and at pressure.	Common alarm
Purity oxygen sensor only	Oxygen content has risen past the alarm point. Usually excessive demand, a system leak, or a separation problem. Confirm there are no active leaks and that supervisory pressure is stable; contact South-Tek if purity does not recover.	Common alarm, where the oxygen sensor is fitted
Compressor or dryer issue	A warning symbol appears on the affected equipment. Check it for power, line leaks and other equipment failures.	Common alarm
Filter	Raised after 1 year or 1,000 run hours, whichever comes first. The status bar flashes Change Filters. It is a maintenance reminder — the generator keeps running. Once the filters are changed, reset it: Alarms → Filter Alarm → Active → Change Filters, then hold the reset button to acknowledge.	No — controller only

▲ Attention — an alarm switched off at the controller reads healthy at the panel The Alarm Settings screens can turn the nitrogen pressure alarm, BlastOff®, the compressor and dryer contacts, and the automatic bypass system itself on or off, and can mute the buzzers. A condition switched off there is not annunciated anywhere — the panel keeps reading healthy for as long as it stays off. Check that every condition the site relies on is switched On before you leave, and record what was enabled. Switching off the Automatic Bypass System disables the changeover itself, and switching off the BlastOff® System disables leak detection itself — not just their alarms. With bypass off, the sprinkler system loses its supplemental air supply during a fill test.

Controller functions

Logs and graphs. SMART-Trak® carries sensor graphing, a sensor data log, a system performance log, an equipment status log, an N2 leakage log and a bypass log. Every unit trends tank pressure; optional sensors add air and nitrogen flow, dew point and inlet temperature. Data exports to micro-SD — press Eject and wait for the safe-to-remove status before pulling the card.
System settings. N2 pressure settings, sensor calibration and bypass settings. Sensor calibration is a two-point linear calibration and the raw figures are specific to your machine — do not copy them from another unit.
Maintenance menu. Valve controls, alarm contact testing and filter status. Alarm Contacts toggles each contact and the audible individually, which is how the panel mapping is proved — see Fire Alarm & BMS Wiring for FPS Generator Dry Contacts.
Product information. Serial number, build date, commission date, software version and total run time — have the serial number from this screen when you open a ticket.
Passcode. Some screens are behind a user password. The passcode on these models is 6557. Factory Settings is password protected for South-Tek technicians only.

⚠ Warning — Valve Controls and forced contacts are impairments Toggling valves or forcing alarm contacts drives the monitoring inputs and interrupts nitrogen supervision — both are fire protection impairments. Before you use either: record the riser's supervisory pressure, notify the building owner or their impairment coordinator and the alarm monitoring company, have the affected points put on test, and tag the system under the site's impairment program. Toggling valves individually needs the unit in Stopped mode with the nitrogen outlet valve closed first, and every valve on that screen returned to Off before you restart. Before you leave: every toggle back to normal, the outlet valve reopened slowly, the unit in Run or Standby, the panel clear, the riser back at the supervisory pressure you recorded, the points off test and the tag cleared.

Leak checking

Leaks make the generator run excessively, shorten its life, wear the compressor and raise BlastOff® alarms. Spray soapy water on connections and watch for bubbling — bubbling means gas is escaping. Where a leak is suspected, isolate the area, disconnect electricity and relieve pressure in the affected section before working on it, then repair or replace with approved parts.

⚠ Warning — this test isolates the riser from nitrogen make-up Closing the nitrogen outlet valve, or relieving pressure in any section, stops nitrogen make-up to the sprinkler system: the test below and any leak repair are fire protection impairments. Notify the building owner or their impairment coordinator and the alarm monitoring company, have the affected points put on test, and tag the system under the site's impairment program before you start. Record the riser's supervisory pressure first — read it at the riser's own gauge or at the panel, not from the generator's tank gauge, which sits upstream of the closed valve. It is what proves at the end that you put the riser back where you found it. Keep the window to the length of the test. Before you leave: reopen the nitrogen outlet valve slowly, confirm the unit returns to Run or Standby, confirm the panel is clear, confirm the riser is back at the pressure you recorded, take the points off test and clear the tag.

To find out whether the loss is inside the generator or out in the sprinkler system:

With the unit powered on, close the nitrogen outlet ball valve — handle across the valve body — and note the storage tank pressure.
Let the generator keep running. It should reach Standby within 10 minutes.
Once it is in Standby, wait 5 minutes. Still in Standby — the generator and its tank are holding, so the leak is downstream of the generator. Back to Running — the leak is inside the generator or the nitrogen storage tank.

When to get support

Contact South-Tek if the generator will not reach Standby, returns to Running without demand, stays in bypass, raises recurring BlastOff® or equipment alarms, or if you suspect a leak inside the cabinet.

Manual download

FPS-10000, FPS-16500, and FPS-22500 O&M Manual

Need help? South-Tek Systems Service — Phone: (910) 415-1880 · Open a support ticket at support@southteksystems911.zendesk.com or through the Help Center.