Honeywell Sensepoint XCD SPXCDULNPX – Fixed C₃H₈ Detector (0-100%LEL, Infrared (dual-beam), UL, LM25, 3/4" NPT)
SPXCDULNPX is the Sensepoint XCD infrared propane LEL transmitter, 0–100 %LEL, LM25 epoxy-coated aluminium, 2 × 3/4" NPT, UL / CSA. Order it for LPG bullet farms and cylinder filling halls where methane IR would under-read.
Same gas, swap enclosure/approval: aluminium SPXCDALMPX, 316SS SPXCDASMPX, UL SPXCDULNPX. SPXCDALMPX · SPXCDASMPX · SPXCDULNPX
Part-number decode
| Segment | Meaning | This SKU |
|---|---|---|
| SPXCD | Sensepoint XCD series | SPXCD |
| A / U | Approval A=ATEX/IECEx/GB; U=UL | U |
| L / S | Enclosure L=LM25 aluminium; S=316SS | L |
| M / N | Entry M=M20; N=3/4" NPT | N |
| PX | Gas propane, Infrared (dual-beam) | PX |
Same gas, swap enclosure/approval: aluminium SPXCDALMPX, 316SS SPXCDASMPX, UL SPXCDULNPX.
Technical specifications
| Target gas | C₃H₈ / propane |
|---|---|
| Principle | Infrared (dual-beam) |
| Default range | 0-100%LEL |
| User FSD window | 20-100%LEL |
| Resolution | 10%LEL |
| Output | 4–20 mA sink/source + optional Modbus RTU |
| Supply | 16–32 VDC (24 VDC nominal) |
| Power | 3.7 W |
| Enclosure | LM25 epoxy-coated aluminium |
| Entries | 2 × 3/4" NPT |
| Display | Tri-colour backlight LCD |
| Relays | 3×5A@250VAC |
| Ingress | IP66 |
| Approvals | UL / CSA |
| Temperature | −40~+65 ℃ |
| Mass | approx. 2.0 kg (4.4 lb) |
Why this principle for this gas
Propane is heavier than air and slides along floors toward pits. Dual-beam IR tuned for C₃ is used so a methane-calibrated pellistor or RX cell cannot hide a rich LPG layer. Mount 200–400 mm above grade, at the pit lip, not on the roof.
Sensor and replaceable parts
OEM cartridge SPXCDXSPXSS. Calibration cap S3KCAL. Collecting cone follows buoyancy—see installation. Pipe/duct kits: SPXCDMTBR / SPXCDDMK.
Typical applications
LPG tank farms, bottle-filling halls and kitchen-gas manifolds need a propane-specific IR trip. XCD gives a hard-wired 4–20 mA to the tank ESD; a handheld only proves the aisle you walked.
Selection contrast
| P/N | Gas | Range | Principle |
|---|---|---|---|
| SPXCDULNPX | C₃H₈ | 0-100%LEL | IR |
| SPXCDULNRX | CH₄ | 0-100%LEL | IR |
| SPXCDULNFX | LEL | 0-100%LEL | Catalytic bead |
| SPXCDULNB1 | CO₂ | 0-2.00%Vol | IR |
| SPXCDALMPX | C₃H₈ | 0-100%LEL | IR |
| SPXCDASMPX | C₃H₈ | 0-100%LEL | IR |
Installation and wiring
Wall-mount SPXCDULNPX (propane, LM25 epoxy-coated aluminium) through the one-piece plate with M8 bolts sized for that mass. This SKU uses 2 × 3/4" NPT entries: pipe kit SPXCDMTBR covers Ø1.5–3″, duct kit is SPXCDDMK, and glands must match—do not retap SPXCDULNPX. Land SPXCDULNPX 4–20 mA as three-wire and set Modbus address from the menu only. Magnetic wand calibration on the SPXCDULNPX lid stays non-intrusive. SPXCDULNPX propane belongs at the pit lip, not the roof.
FAQ
- Does SPXCDULNPX have a display?
- SPXCDULNPX transmitter has a tri-colour backlight LCD for status at a distance. The cartridge itself has no display.
- How does SPXCDULNPX differ from SPXCDUSNPX?
- SPXCDULNPX is complete kit (transmitter + cartridge), LM25 epoxy-coated aluminium (UL), 2 × ¾″ NPT, UL, propane 0-100%LEL. SPXCDUSNPX is the enclosure/approval/entry sibling. SPXCDULNPX is 4–20 mA and relays; for Modbus order SPXCDULNPXM.
- Does SPXCDULNPX need weather protection?
- Outdoors, fit SPXCDWP weather protection on SPXCDULNPX with the sinter down. The cap lengthens T90.
- Does SPXCDULNPX have relays?
- SPXCDULNPX has three relays 5 A @ 250 VAC. Relays are not the EN performance safety function.
- Does SPXCDULNPX carry a China / GB certificate?
- SPXCDULNPX is ordered as UL — it is not a drop-in GB/ATEX nameplate. China GB types are AL/AS SKUs.
- Who supplies SPXCDULNPX and what should I quote?
- Supplied by authorized Honeywell distributor Beijing Dongfang Haitai (GZion). Quote full P/N SPXCDULNPX. SPXCDULNPX is on back order; lead time approx. 10 weeks.
- Can I fit a different-gas cartridge on SPXCDULNPX?
- XCD auto-recognises the same family only (flammable mV/IR, oxygen, toxic EC). Do not mix an O₂ cell onto a flammable/toxic SPXCDULNPX transmitter or the reverse.
Documents
Availability and enquiry
Availability: Not in stock — orders accepted; lead time approx. 10 weeks. Quote full P/N SPXCDULNPX, gas/range and approval.