Honeywell Sensepoint XCD SPXCDASMB2 – Fixed CO₂ Detector (0-5.00%Vol, Infrared (dual-beam), ATEX, 316SS, M20)
SPXCDASMB2 is the Sensepoint XCD infrared carbon dioxide transmitter at 0–5.00 %vol, 316 stainless steel, 2 × M20, ATEX / IECEx / GB. It is the process-range SKU for fermentation heads and bulk CO₂ vaporisers, not the 2 %vol occupied-room B1.
Same gas, swap enclosure/approval: aluminium SPXCDALMB2, 316SS SPXCDASMB2, UL —. SPXCDALMB2 · SPXCDASMB2 · —
Part-number decode
| Segment | Meaning | This SKU |
|---|---|---|
| SPXCD | Sensepoint XCD series | SPXCD |
| A / U | Approval A=ATEX/IECEx/GB; U=UL | A |
| L / S | Enclosure L=LM25 aluminium; S=316SS | S |
| M / N | Entry M=M20; N=3/4" NPT | M |
| B2 | Gas carbon dioxide 5 %vol, Infrared (dual-beam) | B2 |
Same gas, swap enclosure/approval: aluminium SPXCDALMB2, 316SS SPXCDASMB2, UL —.
Technical specifications
| Target gas | CO₂ / carbon dioxide 5 %vol |
|---|---|
| Principle | Infrared (dual-beam) |
| Default range | 0-5.00%Vol |
| User FSD window | Fixed 5.00%Vol |
| Resolution | n/a |
| Output | 4–20 mA sink/source + optional Modbus RTU |
| Supply | 16–32 VDC (24 VDC nominal) |
| Power | 3.7 W |
| Enclosure | 316 stainless steel |
| Entries | 2 × M20 |
| Display | Tri-colour backlight LCD |
| Relays | 3×5A@250VAC |
| Ingress | IP66 |
| Approvals | ATEX / IECEx / GB |
| Temperature | −40~+65 ℃ |
| Mass | approx. 3.1 kg (6.8 lb) |
Why this principle for this gas
At 5 %vol the atmosphere is already an asphyxiation process stream. Dual-beam IR is mandatory; a 2 %vol B1 cell would peg. Mount at the fermentation headspace or vaporiser pit lip, low because CO₂ slumps, and specify 316SS if caustic CIP mist is present.
Sensor and replaceable parts
OEM cartridge —. Calibration cap S3KCAL. Collecting cone follows buoyancy—see installation. Pipe/duct kits: SPXCDMTBR / SPXCDDMK.
Typical applications
Brewhouse fermenters, dry-ice rooms and bulk CO₂ vaporizers need a 5 %vol hard trip. XCD keeps the interlock on the wall; a portable cannot sit in that atmosphere.
Selection contrast
| P/N | Gas | Range | Principle |
|---|---|---|---|
| SPXCDASMB2 | CO₂ | 0-5.00%Vol | IR |
| SPXCDASMB1 | CO₂ | 0-2.00%Vol | IR |
| SPXCDASMRX | CH₄ | 0-100%LEL | IR |
| SPXCDASMO1 | O₂ | 0-25.0%Vol | EChem |
| SPXCDALMB2 | CO₂ | 0-5.00%Vol | IR |
Installation and wiring
Wall-mount SPXCDASMB2 (carbon dioxide 5 %vol, 316 stainless steel) through the one-piece plate with M8 bolts sized for that mass. This SKU uses 2 × M20 entries: pipe kit SPXCDMTBR covers Ø1.5–3″, duct kit is SPXCDDMK, and glands must match—do not retap SPXCDASMB2. Land SPXCDASMB2 4–20 mA as three-wire and set Modbus address from the menu only. Magnetic wand calibration on the SPXCDASMB2 lid stays non-intrusive. SPXCDASMB2 5 %vol CO₂ belongs at the fermenter head or vaporiser pit.
FAQ
- SPXCDASMB2: Can B2 replace B1 in a control room?
- SPXCDASMB2 — No. 5 %vol FSD is too coarse for occupied rooms. Use B1 at 2 %vol.
- SPXCDASMB2: Is there a UL version of B2 in this matrix?
- SPXCDASMB2 — Not in the current published XCD STD list. If UL is mandatory, discuss a different enclosure/entry combination with applications.
- What weight penalty does 316SS add on SPXCDASMB2?
- SPXCDASMB2 is ~6.8 lb versus ~4.4 lb for aluminium sibling SPXCDALMB2. The extra mass buys chloride resistance for this carbon dioxide 5 %vol point; keep M8 wall bolts at the stamped size.
- Can I convert SPXCDASMB2 from ATEX M20 to NPT in the field?
- No. SPXCDASMB2 flameproof entries are machined M20. North-American NPT is UL sibling —, not an adaptor on this ATEX carbon dioxide 5 %vol body.
- Can I retrofit Modbus on SPXCDASMB2 after it ships?
- Modbus RTU on SPXCDASMB2 is a transmitter sales option, not a jumper on the carbon dioxide 5 %vol 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 SPXCDASMB2 or UL — rather than a dead SKU.