Confirm these site and utility requirements before the unit is mounted. The FPS-500 and FPS-900 are compact, wall-mounted systems with a built-in oil-free air compressor, so site preparation is simpler than the larger FPS models that use an external feed compressor — there is no separate air-supply or three-phase power to plan for. Meeting the conditions below helps the system reach and hold purity and avoids preventable startup problems.
Requirements at a glance
| Requirement | FPS-500 & FPS-900 |
|---|---|
| Environment | Indoor, nonhazardous, well-ventilated; 40–100°F (4–38°C) |
| Electrical | 110–120 VAC, 60 Hz, 1-ph — 3.3 A on the FPS-500, 3.5 A on the FPS-900, with total draw bounded at under 8 A. A high-voltage option is available (220 VAC on the FPS-500, 240 VAC on the FPS-900; the panel Design Data lists it at 50 Hz, 1.4 A). The unit's own protection is a 15 A breaker; size the branch circuit to the nameplate and local code |
| Air supply | Built-in oil-free compressor — no external feed air required |
| Nitrogen connection | 1/2" NPT female. Nitrogen supply pressure is up to 70 PSI at the outlet — confirm the system's required supervisory pressure is within that before piping |
| Drain | Two 1/4" OD push-to-connect couplings at the bottom right — one for each filter auto-drain. Run 1/4" OD tube from each, individually, to a floor sink or site drain |
| Clearance | 36" minimum at the front (control panel, connections, front cover) and 6" minimum on the sides. The left side is the ventilation face and carries the valve handles; the drains exit at the bottom right |
| Mounting | Upright on a weight-bearing wall or rack (optional floor-mount kit) |
| Cabinet size and weight | 12-3/4" W × 12" D × 27" H, about 84 lb |
| Nitrogen storage tank | A separate wall-mounted vessel — 15" diameter × 50" tall, allow 55" for manifold clearance. It is not inside the cabinet. Plan wall space and structure for it |
Installation environment
Install the unit indoors in a nonhazardous location. Keep the ambient temperature between 40°F and 100°F (4°C to 38°C) and the area dry. Do not install near a heat source or where steam or water is present. Leave working room around the generator and any associated equipment for routine maintenance and troubleshooting. The unit runs at under 60 dB, and ear protection is required while the equipment is running — factor that into rooms next to occupied space.
If the unit arrives before the room is ready, store it upright — preferably in its shipping box — in a dry, climate-controlled room at 60°F to 80°F, keep gas lines capped and dry so moisture cannot enter at hook-up, and never stack anything on top of it.
Electrical requirements
- Standard power is 110–120 VAC, 60 Hz, single phase — the FPS-500 draws 3.3 A and the FPS-900 draws 3.5 A. Total draw is bounded at under 8 A. A high-voltage option is available — 220 VAC on the FPS-500 and 240 VAC on the FPS-900, listed on the panel Design Data at 50 Hz and 1.4 A; the FPS-900 manual notes that wiring changes apply on that build. The unit is built for one voltage and it is not field-selectable — confirm the built voltage on the nameplate before rough-in.
- The unit's own over-current protection is a 15 A circuit breaker on the cabinet, which is also its On/Off switch. Size the branch circuit and disconnect to the unit nameplate and local code.
- Land the incoming power on the unit's field terminal strip (L1, L2, and ground) — not directly onto the internal power supply. Provide a branch-circuit disconnecting means per local code; the unit's 15 A breaker is its own protection and main power switch, not a substitute for the branch-circuit disconnect.
- Incoming power lands on the field terminal strip behind the 15 A breaker, entering through the 1/2" trade-size conduit hole. Hard-wired terminal-strip connection is the factory standard on both models and no line cord is supplied. If a cord-and-plug variant was ordered, confirm that in writing with South-Tek before rough-in.
- The control panel carries UL 508A open-type industrial control panel certification; electrical schematics are available on request.
Air supply
The FPS-500 and FPS-900 include a built-in oil-free air compressor that supplies the nitrogen generator. No external air source is required. These units are not intended for quick fills — install a separate, suitable air compressor for any other air needs.
Gas and drain connections
All N2-BLAST FPS models are factory-equipped with 1/2" NPT female connections. Double-check every connection location before powering the unit or opening any valve. Both filters have an auto-drain, and the two lines exit through 1/4" OD push-to-connect couplings on the cabinet's bottom right side. Connect each to a safe location — the nearest floor sink or site drain. The figure and legend below are the FPS-500 panel. The FPS-900 legend has 11 items: item 7 is the 1/2" NPT air-bypass ball valve (top), item 8 the red N2-out bypass indicator light, item 9 the UL 508A open ICP label, item 10 the torque-specification label, and item 11 the serial number label. It lists no second 1/2" NPT 3-way ball valve — confirm the valve and connection count on the physical unit and on the job's installation layout drawing before piping.
| # | Component | Function |
|---|---|---|
| 1 | Circuit breaker switch, 15 A | System main power supply |
| 2 | 1/2" trade-size conduit hole | Power supply entry |
| 3 | Audible electric buzzer | Audible alarm |
| 4 | 0–100 PSIG pressure gauge | N2 storage tank pressure |
| 5 | Controller | Unit status (FPS-500 legend) / system controller (FPS-900 legend) |
| 6 | 1/4" OD through-wall coupling | 1/4" OD drain |
| 7 | 1/2" NPT 3-way ball valve | Air bypass (top) |
| 8 | 1/2" NPT 3-way ball valve — some builds | Air in (bottom). Identify the bypass handle by its placard rather than by counting valves |
| 9 | Red light | Bypass indicator |
| 10 | UL 508A open ICP certification label | — |
| 11 | Electrical panel / terminal-block torque spec label | — |
| 12 | Product serial number label | — |
Mounting and clearance
- Mount the unit (~84 lb) upright on a weight-bearing wall or a suitable rack that can support its weight; an optional floor-mount kit is available. Secure the cabinet to the wall at both the top and bottom flanges — failure to do so could cause damage or bodily injury.
- Leave 6" minimum clearance on the sides. The left side is the ventilation face and also carries the 3-way bypass and outlet valve handles (lower left) — never block it. The right side is where both drain couplings exit, so do not push the cabinet tight into a right-hand corner or the drains cannot be run.
- Provide 36" of clearance at the front for access to the control panel, tube/pipe connections, and the front cover. Leave enough room above the cabinet to make and service the top connections.
- Both models use the same wall-mounting bracket kit, STS Part # A05-TYP1-RD (ordered separately), for standard 16" wall-stud spacing. If the studs are not 16" on centre, reinforce the mounting area with 1/2" or thicker plywood before hanging the unit — it vibrates continuously while the compressor runs. Otherwise fasten the cabinet level through its mounting holes. All mounting holes take 1/4" screws and anchors, which are not supplied.
The nitrogen storage tank — plan wall space for it separately
This is the requirement most often missed on these two models, because the cabinet is small and people size the space to the cabinet. The nitrogen storage tank is a separate, wall-mounted pressure vessel — 15" in diameter and 50" tall. Allow 55" of total vertical space so the manifold clears. The 12-3/4" × 12" × 27" cabinet is only part of the footprint.
- Plan a weight-bearing wall for the tank as well as the cabinet, and confirm the structure carries it. The tank is part 800-111-FPS, 15" diameter × 50" tall. Confirm the filled tank weight with South-Tek before planning the lift and the wall structure.
- The tank is secured with a strap assembly and a plastic clip around the body, plus a D-ring assembly fastened to the wall with 1/4" hardware. That hardware is not supplied — it is contractor-provided and has to suit the wall construction.
- The tank carries its own manifold with 1/2" nozzles. Leave room to get at the manifold and the tank ball valves — they are what you close for a leak-isolation test, so they must be reachable without moving anything.
- Plan the run between the cabinet and the tank at layout stage. Both need to be on the same wall or within easy piping reach of each other.
What the installing contractor provides
- 1/4" wall anchors and screws (not supplied) for the cabinet mounting holes and the bracket holes, rated for the 84 lb cabinet plus continuous compressor vibration in the actual wall construction — plus 1/2" or thicker plywood backing if the studs are not 16" on centre.
- A single-phase branch circuit at the unit's built voltage — 120 VAC standard, or the high-voltage option if that was ordered — terminated for hard-wired connection at the unit's terminal strip, with an equipment ground, sized to the nameplate and local code. Confirm the built voltage on the nameplate before pulling the circuit; it is not field-selectable.
- Nitrogen bypass piping for pre-filling, where the job requires it to meet code — this is not standard on every install, so confirm it against the installation layout drawing in the documentation package. (The bypass used for the 30-minute fill test is the manual 3-way handle on the cabinet's left side; that needs no field piping.)
- Drain tubing from both filter auto-drain couplings at the cabinet's bottom right to a floor sink or site drain at a safe location. Run them individually — do not tee them together and do not cap them. An unpiped auto-drain discharges condensate and a jet of air at floor level without warning.
- 1/4" mounting hardware for the nitrogen tank D-ring — not supplied with the unit, and it has to suit the wall construction.
- 1/2" NPT piping, fittings, and thread sealant (PTFE tape or equivalent on all threaded fittings) between the generator, the nitrogen storage tank, and the fire protection system — including the external manual ball valve the tank outlet connects to.
- An air maintenance device on the fire protection system — recommended by South-Tek on the installation arrangement for these models.
- Exhaust routing — a path to vent the generator's exhaust gas outdoors, or written confirmation that the room is large enough and ventilated enough to accept it.
- Signal wiring from the generator to the fire alarm panel or BMS. The unit provides one voltage-free common alarm contact plus a 4–20 mA analog output; receiving equipment is by others. Run this conduit at rough-in — fishing it afterwards is a wall job.
- A sample point for purity verification at the highest point of the riser, where the specification or the AHJ calls for one. This is not a standard inclusion on these models — confirm against the job specification.
Additional piping and hosing
Any additional piping or hosing supplied by others must meet the unit's flow, pressure, and temperature requirements. If the piping run between connected equipment exceeds 50 ft, consult a piping contractor for proper line sizing. Route plumbing to support service access and minimize pressure drop.
Before installation
- Verify the exact model number on the nameplate.
- Confirm the room holds 40–100°F, is well ventilated and not sealed off from normal air changes, and that the route for venting the generator's exhaust gas is on the drawings.
- Confirm the mounting surface is a weight-bearing wall or suitable rack able to carry 84 lb under continuous vibration, that studs are 16" on centre or the area is backed with 1/2"+ plywood, and that 1/4" anchors are on site.
- Confirm the electrical service matches the unit's built voltage and lands on the field terminal strip, and that a branch-circuit disconnecting means is provided.
- Plan both filter auto-drain runs from the cabinet's bottom right to the floor sink or site drain before mounting.
- Confirm wall space and structure for the 50"-tall nitrogen tank as well as the cabinet, and that the 1/4" D-ring hardware is on site.
- Confirm the signal conduit to the fire alarm panel or BMS is on the drawings.
- Confirm the location holds 36" clear at the front and 6" clear on the sides, with the left-side ventilation face and the bottom-right drains unobstructed.
- Review the panel and gas-connection layout above, and the installation layout drawing in the documentation package, before startup.
Related articles
- N2-BLAST Fire Protection Systems Overview
- FPS-500 and FPS-900 Overview
- FPS-500 and FPS-900 Installation and Startup
- FPS-500 and FPS-900 Operation and Alarms
- FPS-500 and FPS-900 Preventive Maintenance