The Rosemount 848T is the multi-input member of the temperature family: one transmitter that reads many sensors, to cut home-run wiring and I/O count. The model code has three required positions and a compact option set, plus a wireless variant. This guide explains how to read it with the Rosemount 848T Decoder, anchored to Emerson PDS 00813-0100-4697 Rev SD (August 2024).
Output Sets Protocol and Channel Count
The first required position, the transmitter output, does double duty: it selects both the communication protocol and the number of sensor channels. FOUNDATION Fieldbus (F) reads eight sensor channels. WirelessHART (X) reads four. There is no HART 4-20 mA single-loop output on the 848T; it is a digital, multi-channel device by design.
If a point count above four must go on one wireless device, the wireless 848T cannot do it; that is a Fieldbus 848T or two wireless units. The decoder states the channel count the output implies so the device-versus-point-count decision is grounded.
Rosemount 848T Multi-Input Temperature Decoder
Decode a Rosemount 848T multi-input temperature transmitter model code (FOUNDATION Fieldbus 8-channel or WirelessHART 4-channel) against Emerson PDS 00813-0100-4697 Rev SD. Reads output, product certification, input type, and the full option string. Enforces the S002 certification set and the wireless enclosure requirement. Source-cited every position.
Certification and Input Type
The second required position is a two-character product certification (intrinsic safety, FISCO, Type n, Division 2, Dust, and the regional and combination codes). The third is the input type: S001 accepts RTD, thermocouple, mV, and ohm inputs; S002 adds 4-20 mA inputs so the 848T can aggregate the outputs of other analog transmitters, not just raw sensors.
Several certifications (Type n, Division 2, Dust: N1, N3, N5, N7, ND) require an enclosure. The decoder carries the merged certification list from both the Fieldbus and wireless sections of the PDS and cites each to its page.
The S002 Certification Trap
S002 looks like a free upgrade: more input flexibility for the same device. But it carries a narrow certification set. On the Fieldbus 848T, S002 is only offered with certifications N1, N5, N6, NC, NK, and NA. On the wireless 848T, it is only NA and N5. So if a spec needs both 4-20 mA inputs (S002) and an intrinsic-safety certification like I1, that combination is simply not buildable, and the order will bounce.
The decoder fires a constraint warning when S002 pairs with a certification outside its allowed set, so the conflict surfaces at decode time rather than at the factory.
Wireless Build Requirements and the Channel Map
A wireless 848T (output X) is not complete with just the X character. It requires a wireless enclosure (HA1 cable glands or HA2 conduit entries), a wireless antenna option (WK1 long-range integral or WM1 extended-range external), and the update-rate option (WA3). The decoder warns if the enclosure is missing and flags wireless-only options that appear on a Fieldbus build.
Finally, as with the rest of the temperature family, the per-channel sensor type is configured on the device, not encoded in the model code. Given how much of the 848T lives in per-channel configuration, the Configuration Data Sheet (ordered with option C1) is usually the only place the real channel map exists. Decode the model code for protocol, channel count, and certification; pull the CDS for the channel assignments.