ABB 826A001B-1

Overview
The ABB 826A001B-1 is a dedicated power supply module designed for use with ABB’s legacy control platforms, including the Procontic S100, MOD 300, and early Advant OCS systems. This module converts incoming AC mains voltage to regulated DC power required by the backplane, I/O modules, and CPU cards. Built for industrial reliability, the 826A001B-1 features overvoltage, overcurrent, and short-circuit protection. While newer ABB systems have moved to more compact power supplies, this unit remains essential for maintaining legacy installations in power generation, chemical processing, and heavy manufacturing facilities where system replacement is not yet economical.

Parameters 

Key Features

• Universal input selection (120/240 V AC via jumper)
• Triple regulated outputs: +5 V DC (8 A) , +15 V DC (1 A) , -15 V DC (1 A)
• LED status indicators: Power OK (green) , Overload (yellow – flashing)
• Remote sense capability on +5 V output (compensates for voltage drop)
• Over-temperature shutdown with auto-recovery (internal sensor, 85°C threshold)
• Screw terminal barrier strip for field wiring (captive screws, 12–22 AWG)
• Input fuse accessible from front panel (5×20 mm, slow-blow, user replaceable)
• Metal chassis with ground stud for functional earth connection
• Output adjust potentiometer (+5 V: 4.75–5.25 V range)

Structure & Composition

The 826A001B-1 is housed in a heavy-duty ventilated steel enclosure painted in ABB’s characteristic light gray (RAL 7035). The module is not designed for DIN rail mounting; instead, four slotted mounting tabs allow secure attachment to a backplate or chassis using M4 screws.

Internally, the assembly follows a linear + switching hybrid topology:

• Input stage: EMI filter (common-mode choke + X/Y capacitors), followed by a voltage selector jumper (series/parallel configuration for 120/240 V operation) and a slow-blow 2 A fuse
• Rectification & bulk storage: Full-wave bridge rectifier (GBU406) and two 470 μF / 400 V electrolytic capacitors
• Main converter: Flyback topology using a MOSFET (600 V, 4 A) controlled by a UC3844 PWM controller
• Transformers: Two separate ferrite-core transformers — one for +5 V rail, one for ±15 V rails (post-regulated from a common winding)
• Output stage: Schottky rectifiers (30 A rated), LC filters (ferrite beads + 3300 μF low-ESR capacitors), and linear post-regulators (LM723 for ±15 V rails)
• Protection circuitry: Crowbar SCR (6.2 V threshold) on +5 V output; foldback current limiting using sense resistors

Applications

• Powering ABB Procontic S100 racks (CPU, I/O, communication modules)
• Advant OCS 110/210 system backplane supply
• MOD 300 process controller chassis (PLC mainframe)
• Legacy turbine control systems (Westinghouse/ABB combined cycle plants)
• Spare part replacement for installed base in oil refineries and chemical plants
• Re-powering legacy panel-mount ABB indicator and controller blocks
• Test bench power source for vintage ABB modules (requires load resistors for stability)

Installation & Maintenance

Mounting

• Locate the 826A001B-1 inside a NEMA 12 or IP54 minimum enclosure
• Mount vertically (preferred for convection cooling) using four M4 screws through the slotted tabs
• Maintain 50 mm clearance above and below for airflow
• Do not mount directly above heat-generating devices (e.g., large contactors, variable frequency drives)

Wiring

• Input AC: Connect L (live) and N (neutral) to terminals L1 and L2 (use 14 AWG, 90°C rated copper wire). Connect ground wire to the chassis ground stud (green/yellow, ring terminal)
• Voltage selection: Set jumper J1 for 115 V (parallel primary) or 230 V (series primary) before applying power
• Output DC: Connect +5 V, COM, +15 V, COM, -15 V to the backplane or distribution terminal block. Use 16 AWG for +5 V (current up to 8 A)
• Remote sense (optional): Connect +SENSE and -SENSE wires from the load point back to the module (twisted pair). If not used, install shorting jumpers on the sense terminals
• Torque: Screw terminals 0.5–0.6 N·m (4.4–5.3 lb-in)

Startup & Testing

• Verify correct input voltage selection jumper position
• Measure outputs before connecting load: +5 V ±2% , +15 V ±3% , -15 V ±3%
• Check ripple: Use oscilloscope (20 MHz BW limit) — should be <50 mV p-p
• Green LED: Normal operation. Yellow flashing LED indicates overload or thermal derating

Maintenance

• Annually:
  • Clean ventilation slots with compressed air (max 30 psi, from inside out)
  • Check input fuse (2 A 250 V slow-blow, 5×20 mm) — replace only with identical type (Bussmann S506-2A or Littelfuse 218002)
  • Inspect electrolytic capacitors for bulging or venting
  • Measure output voltages under load; adjust +5 V potentiometer (VR1) if drifted beyond ±2%
• Every 5–7 years: Replace primary electrolytic capacitors (470 μF / 400 V, 105°C rated, Panasonic ED series or equivalent)
• Every 10 years or at failure: Full module replacement (capacitor aging leads to excessive ripple and hold-up time reduction)

Troubleshooting

Additional Information

Ordering & Substitutions

• Original part number: 826A001B-1 (also listed as 826A001B-1/A, 826A001B-1/B)
• Obsolete status: Discontinued by ABB in 2015. Replacement options:
  • Direct plug-compatible: ABB 826A001B-2 (updated capacitors, higher MTBF, still end-of-life)
  • Non-OEM replacement: RSP-150-5 (Mean Well) + DRA-15-15 (two supplies) — requires rewiring of ±15 V rails
  • NOS (new old stock): Available through Radwell, PLC Center, or EU Automation (verify revision)
• Legacy cross-references: Bailey INFI 90 (NIMP01), Siemens S5 (6ES5951-7LB21) — not directly interchangeable

Certifications & Compliance

• CE (EMC Directive 89/336/EEC, as originally certified)
• UL 508 (File E135881, for industrial control equipment)
• RoHS (lead-free solder, exempt for high-temperature tin-lead on connectors)
• Not rated for hazardous locations (Zone 2/Div 2 installations require external enclosure)

Accessories (purchased separately)

• Backplane power cable: 14-pin Molex to screw terminal (ABB part# 826A900C-1)
• Mounting plate adapter for DIN rail (third-party, not ABB branded)
• Replacement fuse kit (5 pieces, ABB part# 826A800F-1)

Documentation

• Installation instruction: 3BSE020931 (English, 12 pages)
• Maintenance & repair manual: 1KGT 150 890 (restricted to ABB service centers)
• Schematic diagram: 826A001B-1_SCH (available upon request for authorized repair shops)

Environmental & End-of-Life

• Disposal: WEEE Category 8 (industrial electronics). Contains lead in solder (RoHS exempt), aluminum electrolytic capacitors (requires separation), and flame-retardant plastics (UL 94 V-0). Return to ABB authorized recycling partner.