ABB PHARPS32200000 Harmony Rack Power Supply – 24 V DC 10 A, 120/240 V AC Input, INFI 90 / Symphony Spare

Description

Technical Specifications

Main Features and Advantages

Dual AC/DC input covers plant battery and AC branch in one SKU.​ The standout spec of ABB PHARPS32200000​ is its 85–264 V AC and 110–300 V DC input window. In a typical coal or hydro plant, the DCS cabinet has two feeds: a 120 V AC branch from the MCC/UPS, and a 125 V DC feed from the station battery (which rides through generator trips and grid blackouts). Most DCS PSUs force you to pick AC-input or DC-input at procurement; ABB PHARPS32200000​ takes either, auto-sensing, no jumper. This means one spare covers both feed types across the plant, and in redundant-pair config (two ABB PHARPS32200000​ + diode-OR) the rack can lose the AC branch and ride on DC, or vice versa. For plants that standardized Harmony in the 1990s, this dual-input was Bailey’s answer to “keep the DCS alive during a station blackout”—the 125 V DC battery holds the PSU, which holds the HC/HCU, which holds turbine governing and BOP sequencing through the black-start.10 A / 240 W sized for a full Harmony rack.​ The ABB PHARPS32200000​ 24 V DC 10 A rating comfortably feeds a fully populated Harmony rack: HC controller (≈2–3 A), IM + NPM (≈1–2 A), plus 6–10 I/O or function modules (≈0.3–0.8 A each). A single ABB PHARPS32200000​ covers most single-PSU Harmony cabinets (smaller BOP drops, auxiliary skids); larger CCR cabinets run redundant pairs (1+1) for N+1. The 24 V DC output regulation holds ±1–2 % across load and input variation, which matters because the Harmony backplane feeds sensitive analog I/O (Bailey INF I/AIN modules) whose 4–20 mA loop accuracy degrades if the 24 V DC bus sags under load-step (e.g., when a bank of DO modules all pick contactors simultaneously). The ABB PHARPS32200000​ transient response is tuned for this—Bailey specified it against the worst-case I/O inrush profile of a full rack.Redundancy with diode-OR, hot-swap capable.​ Two ABB PHARPS32200000​ units seat in the Harmony rack’s left-end PSU slots and feed a diode-OR module (PHARPSR01) on the rack’s 24 V DC busbar. Under normal load, both share ~50/50; if one trips (overload, AC loss, internal fault), the other picks the full load within the PSU’s hold-up time (<20 ms typical), and the DC-OK LED on the failed unit goes dark while DC-OK on the mate stays lit. The failed unit can be extracted and replaced live—the HC/HCU never sees the 24 V DC bus drop. This is the standard architecture in turbine-control and BOP Harmony drops where a DCS reboot costs five-figure ramp loss. For plants mid-lifecycle (15–20 years), the ABB PHARPS32200000​ electrolytics are usually the first planned-replacement item—proactive swap during a turnaround weekend avoids an in-season failure.Fanless convection for 20-year cabinet life.​ Like the Emerson Ovation PSU covered earlier, ABB PHARPS32200000​ is convection-cooled through vent slots in the Bailey beige housing, no fan, no bearings, no airflow path pulling coal-dust or sugar-mill particulate through the PCB. In a 25-year-old Harmony cabinet in a Pakistani coal plant or a Brazilian pulp mill, the PSU fan would have been replaced 3× by now—ABB PHARPS32200000​ just runs. The trade-off is derating above ~50 °C ambient; Harmony cabinets in turbine bays are typically climate-controlled or forced-ventilated, so the rating matches.