Product Overview
The ABB 3BHE024855R0103 is an 8-channel universal analog input (AI) module in ABB’s UAD-series I/O family, engineered for Symphony Plus and legacy INFI 90 distributed control system (DCS) architectures. Where the previously covered ABB 3BHE012095R0002 (UAD141A02) pushes setpoints out to the field as an AO, the ABB 3BHE024855R0103 is the input-side counterpart — acquiring 4–20 mA, 0–20 mA, or 0–10 V signals from field transmitters, pressure cells, temperature transmitters, flow meters, and analyzers, converting them to digital via 16-bit A/D per channel, and handing the data up to the control processor over the UAD backplane bus. In plain plant terms: this is the DCS card that tells the controller what the field is actually doing.
Each channel on the ABB 3BHE024855R0103 is software-selectable between current and voltage ranges through the Symphony engineering tool — no DIP switches, no jumper blocks. Default is 4–20 mA with 250 Ω precision shunt, but any channel can be flipped to 0–10 V (high-impedance input) without hardware changes, so a single card can mix a 4–20 mA flow transmitter on channel 1, a 0–10 V position feedback on channel 2, and a 0–20 mA chemical-dose signal on channel 3. Galvanic isolation is ≥ 500 V DC between channels and backplane, protecting the UAD rack from field-side ground faults and inductive transients that routinely appear on transmitter loops in power and hydrocarbon plants.
Positioned as a “Basic Module” in the UAD tier structure, the ABB 3BHE024855R0103 omits HART passthrough and some of the premium-AI enhanced diagnostics, but retains the 16-bit resolution, ±0.1 % FS accuracy, and open-wire detection that cover the vast majority of DCS loops — making it the volume AI spare in most Symphony / INFI 90 stores. For INFI 90 plants doing lifecycle extension without a full DCS rip-and-replace, the ABB 3BHE024855R0103 is the current-production RCI that keeps 1990s-vintage function-code logic running unchanged: same UAD mechanical footprint, same backplane, same function-code block mapping — swap in, download parameters, move on.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 3BHE024855R0103 |
| Manufacturer | ABB (Hitachi Energy) |
| Product Type | Analog Input Module, Basic Tier |
| Series | UAD Series (Symphony Plus / INFI 90 compatible) |
| Number of Channels | 8 (independent, software-configurable) |
| Input Types | 4–20 mA, 0–20 mA, 0–10 V |
| Resolution | 16-bit per channel |
| Accuracy | ±0.1 % of full scale (25 °C reference) |
| Current Input Impedance | 250 Ω precision shunt |
| Voltage Input Impedance | > 1 MΩ |
| Channel Isolation | ≥ 500 V DC (channel↔channel & channel↔backplane) |
| Diagnostics | Open-wire / broken-transmitter detect (current mode) |
| Mounting | Plugs into UAD baseplate (e.g., UAD140A) |
| Operating Temp | 0 °C to +60 °C |
| Protection | IP20 (cabinet installation) |
Main Features and Advantages
The ABB 3BHE024855R0103 earns its place in the DCS I/O cabinet by offering the input-side mirror of what the UAD141A02 AO delivers — clean acquisition, software flexibility, and retrofit sanity — three things that matter on a 20-year process unit.
Software-configurable per channel: Each of the eight channels on the ABB 3BHE024855R0103 can be independently set to 4–20 mA, 0–20 mA, or 0–10 V through the Symphony engineering tool. A single card thus serves mixed instrumentation — flow (4–20 mA), tank level (4–20 mA with two-wire TX), analyzer (0–10 V from a 4–20 mA→0–10 V isolator), and position feedback (0–10 V from a potentiometer-style rider) — all on one ABB 3BHE024855R0103. This halves the spare-part SKU count compared to fixed-type AI cards and prevents the “we ordered the 4–20 mA version but this loop is 0–10 V” misfire that plagues stores buying blind from BOMs.
16-bit resolution with ±0.1 % FS accuracy: The A/D chain on the ABB 3BHE024855R0103 delivers 65536 counts across span, meaning a 4–20 mA loop resolves to ≈ 0.00024 mA per count — more than enough for flow totals, level averaging, and pressure cascade where 12-bit cards start to show quantisation尤其在 slow-loop trending. For plants still running 12-bit legacy AI cards, swapping to the ABB 3BHE024855R0103 often reveals previously invisible process variability (valve stiction, TX drift) because the DCS now sees finer granularity.
Galvanic isolation & open-wire detection: The ≥ 500 V DC barrier between channels and backplane means a grounded field loop on channel 4 won’t drag down channel 5 or crash the UAD rack — important in plants where transmitter loops share conduit with 480 V motor feeds. On current mode, the ABB 3BHE024855R0103 detects open-wire (broken TX, loose terminal, TX power loss) and flags a diagnostic bit to the controller, so the DCS can force the loop to manual or substitute a last-good-value rather than letting a hidden broken wire drift the process. On voltage mode the module flags over-range.
Retrofit continuity: For INFI 90 plants migrating to Symphony Plus (or just keeping INFI 90 alive past obsolescence), the ABB 3BHE024855R0103 is the kind of module that keeps migration budgets sane. Same UAD mechanical footprint, same backplane, same function-code mapping — the ABB 3BHE024855R0103 drops in where an older UAD AI or legacy INFI 90 IMDSI/IMDSM used to sit. The “Basic Module” badge means you’re not paying for HART or enhanced per-channel diagnostics on loops that don’t need them (temperature scan, vessel level, header pressure) — reserve the premium-AI slots for loops that truly need HART trim, like smart valve positioners or multivariable TXs.
Build pedigree follows ABB’s DCS standard: conformal coating on the ABB 3BHE024855R0103 PCB, industrial-grade A/D and isolation components rated for continuous duty, and the same MTBF expectations as the rest of the Symphony I/O line (15+ year service life typical). The card plugs into a UAD baseplate (commonly UAD140A) that also hosts the ABB 3BHE012095R0002 AO and sibling DI/DO slices, so a single baseplate can mix 8 AI + 8 AO + 16 DI + 16 DO in one short Eurocard stack — clean, dense, and backplane-powered.
