Honeywell Sensepoint XCD SPXCDASMO1 – Fixed O₂ Detector (0-25.0%Vol, Electrochemical (Surecell™), ATEX, 316SS, M20)
SPXCDASMO1 is the Sensepoint XCD oxygen deficiency / enrichment transmitter, fixed 0–25.0 %vol electrochemical cell, 316 stainless steel, 2 × M20, ATEX / IECEx / GB. It is the dedicated O₂ SKU for nitrogen-purged vessels, confined plant rooms and inerting skids.
Same gas, swap enclosure/approval: aluminium SPXCDALMO1, 316SS SPXCDASMO1, UL SPXCDULNO1. SPXCDALMO1 · SPXCDASMO1 · SPXCDULNO1
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 |
| O1 | Gas oxygen, Electrochemical (Surecell™) | O1 |
Same gas, swap enclosure/approval: aluminium SPXCDALMO1, 316SS SPXCDASMO1, UL SPXCDULNO1.
Technical specifications
| Target gas | O₂ / oxygen |
|---|---|
| Principle | Electrochemical (Surecell™) |
| Default range | 0-25.0%Vol |
| User FSD window | Fixed 25.0%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
Oxygen is neither heavier nor lighter in a meaningful way for siting—the risk is displacement by N₂ or enrichment from leaks. A Surecell™ O₂ cell is used because catalytic and IR channels cannot report %vol oxygen. Mount at the height where personnel breathe or where the purge first enters; do not hide it behind a vessel skirt.
Sensor and replaceable parts
OEM cartridge SPXCDXSO1SS. Calibration cap S3KCAL. Collecting cone follows buoyancy—see installation. Pipe/duct kits: SPXCDMTBR / SPXCDDMK.
Typical applications
Nitrogen-inerted tanks, analyser houses and bottle stores need a latched O₂ trip, not a walk-around reading. XCD gives 4–20 mA plus relays so the purge skid can hard-interlock; a portable cannot hold that permit.
Selection contrast
| P/N | Gas | Range | Principle |
|---|---|---|---|
| SPXCDASMO1 | O₂ | 0-25.0%Vol | EChem |
| SPXCDASMHX | H₂S | 0-50ppm | EChem |
| SPXCDASMCX | CO | 0-300ppm | EChem |
| SPXCDASMFX | LEL | 0-100%LEL | Catalytic bead |
| SPXCDALMO1 | O₂ | 0-25.0%Vol | EChem |
| SPXCDULNO1 | O₂ | 0-25.0%Vol | EChem |
Installation and wiring
Wall-mount SPXCDASMO1 (oxygen, 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 SPXCDASMO1. Land SPXCDASMO1 4–20 mA as three-wire and set Modbus address from the menu only. Magnetic wand calibration on the SPXCDASMO1 lid stays non-intrusive. Aim the SPXCDASMO1 O₂ head at the purge inlet or the breathing line.
FAQ
- SPXCDASMO1: Can I change the 25 %vol O₂ FSD?
- SPXCDASMO1 — No. The O1 cell is fixed at 25.0 %vol. If you need a different span you are specifying the wrong platform.
- SPXCDASMO1: How often is an oxygen cell replaced?
- SPXCDASMO1 — Plan 12–18 months in continuously powered service. Keep SPXCDXSO1SS on the shelf; oxygen cells age even in the box once the foil is broken.
- What weight penalty does 316SS add on SPXCDASMO1?
- SPXCDASMO1 is ~6.8 lb versus ~4.4 lb for aluminium sibling SPXCDALMO1. The extra mass buys chloride resistance for this oxygen point; keep M8 wall bolts at the stamped size.
- Can I convert SPXCDASMO1 from ATEX M20 to NPT in the field?
- No. SPXCDASMO1 flameproof entries are machined M20. North-American NPT is UL sibling SPXCDULNO1, not an adaptor on this ATEX oxygen body.
- Can I retrofit Modbus on SPXCDASMO1 after it ships?
- Modbus RTU on SPXCDASMO1 is a transmitter sales option, not a jumper on the oxygen 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 SPXCDASMO1 or UL SPXCDULNO1 rather than a dead SKU.