Honeywell XNX XNX-UTSE-MHNNN – no sensor (transmitter body), EC, UL, 316SS, 3/4" NPT
XNX-UTSE-MHNNN is a Honeywell XNX EC-personality transmitter body, UL / cUL, 4 × 3/4" NPT, 316 stainless steel, Modbus RTU + 4–20 mA HART, local HART port on the transmitter, no cell. Toxic and oxygen XNX electrochemical sensors mate here; catalytic LEL and MPD IR do not.
Same sensor, swap enclosure/approval: aluminium XNX-UTAE-MHNNN, 316SS XNX-UTSE-MHNNN, other approval XNX-AMSE-MHNNN. XNX-UTAE-MHNNN · XNX-UTSE-MHNNN · XNX-AMSE-MHNNN

Part-number decode
| Segment | Meaning | This SKU |
|---|---|---|
| XNX | Honeywell XNX universal transmitter | XNX |
| A / U | Approval A=ATEX/IECEx; U=UL/cUL | U |
| M / T | Entry M=M25; T=3/4" NPT | T |
| A / S | Enclosure A=aluminium; S=316SS | S |
| V / I / E | Personality V=mV(MPD); I=IR Optima/Excel; E=EC | E |
| N / R / M / F | Option N=HART only; R=relays; M=Modbus; F=FFB | M |
| N / H | Local HART port N=no; H=yes | H |
| NNN | no sensor (transmitter body) | NNN |
Same sensor, swap enclosure/approval: aluminium XNX-UTAE-MHNNN, 316SS XNX-UTSE-MHNNN, other approval XNX-AMSE-MHNNN.
Technical specifications
| Category | 变送器本体 |
|---|---|
| Personality | EC personality (toxic / oxygen electrochemical) |
| Sensor / range | no sensor (transmitter body) |
| Target | body / sensor not fitted |
| Principle | personality board only |
| Output | Modbus RTU + 4–20 mA HART |
| Local HART | local HART port on the transmitter |
| Supply | 16–32 VDC (24 VDC nominal) |
| Enclosure | 316 stainless steel |
| Entries | 4 × 3/4" NPT |
| Display | Backlit LCD, magnetic-wand menus |
| Ingress | IP66 |
| Approvals | UL / cUL |
| Temperature | −40~+65 ℃ |
| Mass | approx. 5.0 kg |
| Mates with | XNX electrochemical toxic and oxygen cells |
Why this personality / sensor
Electrochemical cells need bias, temperature compensation and a different connector than the mV MPD. This personality is the XNX answer to H₂S, CO, O₂, Cl₂ and other toxics on the XNX EC list. Do not buy it to run a pellistor.
Personality and replaceable parts
XNX-UTSE-MHNNN uses the EC personality (toxic / oxygen electrochemical) board and mates with XNX electrochemical toxic and oxygen cells. This SKU ships without a sensor; order the head by gas. Spares live on product-3991. Do not substitute Sensepoint XCD cartridges on XNX.
Typical applications
Water-treatment H₂S, boiler-house CO, nitrogen-purge O₂ and chlorine rooms keep the transmitter on the wall and swap EC cells on a 12–24 month cycle. The body SKU is what you stock when the gas list is still being written.
Selection contrast
| P/N | Gas | Range | Option | Body |
|---|---|---|---|---|
| XNX-UTAE-MHNNN | body | — | Modbus | Aluminium |
| XNX-AMSE-MHNNN | body | — | Modbus | 316SS |
| XNX-UTSE-NHNNN | body | — | HART | 316SS |
| XNX-UTSE-RHNNN | body | — | Relays | 316SS |
| XNX-UTSE-FHNNN | body | — | FFB | 316SS |
Installation and wiring
Wall-mount XNX-UTSE-MHNNN (316 stainless steel, approx. 5.0 kg) on a rigid stand sized for that mass. This SKU uses 4 × 3/4" NPT entries—glands must match; do not retap XNX-UTSE-MHNNN. Land XNX-UTSE-MHNNN 4–20 mA HART per the loop drawing; relays/Modbus/FFB exist only on the matching option board. Magnetic-wand menus on the XNX-UTSE-MHNNN lid stay non-intrusive. XNX-UTSE-MHNNN is a body: wall-mount the transmitter first and mate the head after the personality is confirmed—do not buy a configured SKU until the gas is frozen.
FAQ
- Can I add an MPD sensor to XNX-UTSE-MHNNN later?
- XNX-UTSE-MHNNN ships as a transmitter body. mV personalities accept MPD CB1/IV1/IF1/IC1 heads; IR personalities need Optima/Excel; EC personalities need XNX electrochemical cells. Do not mix those three families on this board.
- Is XNX-UTSE-MHNNN a complete gas detector?
- No. XNX-UTSE-MHNNN is electronics and enclosure only. A configured detector has a three-character sensor code such as CB1 instead of NNN.
- Why is XNX-UTSE-MHNNN 316SS instead of aluminium?
- XNX-UTSE-MHNNN is the marine/sour-service body (~5 kg). Inland dry rooms can take aluminium sibling XNX-UTAE-MHNNN and save mass on the bracket.
- Why is XNX-UTSE-MHNNN NPT instead of M25?
- XNX-UTSE-MHNNN is the UL/cUL body and ships 3/4" NPT. Do not tap M25 on this lid—order ATEX sibling XNX-AMSE-MHNNN if metric glands are mandatory.
- Can I retrofit Foundation Fieldbus on XNX-UTSE-MHNNN after it ships?
- No. XNX-UTSE-MHNNN is the Modbus RTU option board. FFB is a different sales option (XNX-UTSE-FHNNN), not a jumper on this lid.
Documents
Honeywell XNX datasheet / manual · On-site XNX selection matrix
Availability and enquiry
Stock is lot-based. If this box is out, jump to 316SS XNX-UTSE-MHNNN or UL XNX-UTSE-MHNNN rather than a dead SKU.