Honeywell Sensepoint XCD SPXCDULNG1 – Fixed H₂ Detector (0-1000ppm, Electrochemical (Surecell™), UL, LM25, 3/4" NPT)
SPXCDULNG1 is the Sensepoint XCD hydrogen electrochemical transmitter, fixed 0–1000 ppm, LM25 epoxy-coated aluminium, 2 × 3/4" NPT, UL / CSA. It is the ppm-level H₂ leak SKU for battery rooms and electrolyser halls, not a %LEL catalytic detector.
Same gas, swap enclosure/approval: aluminium SPXCDALMG1, 316SS SPXCDASMG1, UL SPXCDULNG1. SPXCDALMG1 · SPXCDASMG1 · SPXCDULNG1
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 |
| G1 | Gas hydrogen, Electrochemical (Surecell™) | G1 |
Same gas, swap enclosure/approval: aluminium SPXCDALMG1, 316SS SPXCDASMG1, UL SPXCDULNG1.
Technical specifications
| Target gas | H₂ / hydrogen |
|---|---|
| Principle | Electrochemical (Surecell™) |
| Default range | 0-1000ppm |
| User FSD window | Fixed 1000ppm |
| Resolution | n/a |
| 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
Hydrogen is much lighter than air and jets to the highest ceiling pocket. The G1 Surecell™ is a toxic-range electrochemical cell for early leak detection; it is not a 0–100 %LEL pellistor. Mount at the roof ridge or above the battery racks and fit a collecting cone because H₂ will otherwise bypass a wall sensor.
Sensor and replaceable parts
OEM cartridge SPXCDXSG1SS. Calibration cap S3KCAL. Fit a collecting cone on hydrogen; do not cone a heavier-than-air H₂S head. Pipe/duct kits: SPXCDMTBR / SPXCDDMK.
Typical applications
UPS battery rooms, electrolyser containers and hydrogen tube-trailer bays need a fast ppm trip before the cloud reaches LEL. XCD can sit outside the container with a remote head on the ceiling—again a portable cannot hold that point.
Selection contrast
| P/N | Gas | Range | Principle |
|---|---|---|---|
| SPXCDULNG1 | H₂ | 0-1000ppm | EChem |
| SPXCDULNCX | CO | 0-300ppm | EChem |
| SPXCDULNFX | LEL | 0-100%LEL | Catalytic bead |
| SPXCDULNHX | H₂S | 0-50ppm | EChem |
| SPXCDALMG1 | H₂ | 0-1000ppm | EChem |
| SPXCDASMG1 | H₂ | 0-1000ppm | EChem |
Installation and wiring
Wall-mount SPXCDULNG1 (hydrogen, 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 SPXCDULNG1. Land SPXCDULNG1 4–20 mA as three-wire and set Modbus address from the menu only. Magnetic wand calibration on the SPXCDULNG1 lid stays non-intrusive. SPXCDULNG1 hydrogen must sit on the ceiling with a collecting cone.
FAQ
- SPXCDULNG1: Is G1 a flammable LEL detector?
- SPXCDULNG1 — No. 0–1000 ppm is a leak range. For 0–100 %LEL hydrogen you need a different sensing principle and SKU family.
- SPXCDULNG1: Do I need a collecting cone?
- SPXCDULNG1 — Yes for hydrogen. Unlike H₂S, H₂ rises; the Honeywell weather/collecting cone is recommended on ceiling mounts.
- LM25 or 316SS for SPXCDULNG1 (hydrogen)?
- SPXCDULNG1 ships in LM25 epoxy aluminium (~4.4 lb). For hydrogen in salt spray, caustic CIP or sour-water splash, switch to 316SS sibling SPXCDASMG1 instead of painting this lid.
- Why is SPXCDULNG1 NPT instead of M20?
- SPXCDULNG1 is the UL/CSA hydrogen body and ships 3/4" NPT. Do not tap M20 on this lid—order ATEX sibling SPXCDALMG1 if metric glands are mandatory.
- Can I retrofit Modbus on SPXCDULNG1 after it ships?
- Modbus RTU on SPXCDULNG1 is a transmitter sales option, not a jumper on the hydrogen lid. Confirm the option before the box leaves; 4–20 mA sink/source is already on this SKU.
Documents
Honeywell Sensepoint XCD datasheet / manual · On-site XCD selection matrix
Availability and enquiry
Stock is lot-based. If this aluminium ATEX box is out, jump to 316SS SPXCDASMG1 or UL SPXCDULNG1 rather than a dead SKU.