ABB UN 0950a-P VAR.1 Frequency Matcher Module

Key Features

Technical Specifications

Applications

The UN 0950a-P VAR.1 is utilized in power generation and industrial synchronization systems:

• Power Generation: Synchronous generator synchronization and paralleling

• UNITROL 500/1000 Systems: Frequency matching sub-board within excitation regulation cabinets

• Utility Substations: Frequency matching for grid connection

• Marine Applications: Shipboard power generation synchronization

Important Notes

• Legacy Component: This module is part of a legacy ABB product line. The UNITROL 500 series is in a "last-time-buy" window, and the HEIR445976R1 is a consumable spare part for maintaining existing systems .

• Part Number Variations: The part number may appear in supplier listings as UN 0950a-P VAR.1, UN0950A-PV1, or with alternate references HEIR445976R1 / HEIR445976R0001 . These variations typically refer to the same underlying product.

• Revision Compatibility: R1 = R0001 and V1 = VAR.1. Whether R1/V1 can be mixed with older R0/V0 revisions must be verified against ABB PCN documentation—do not assume "UN0950A-P universal" without confirmation .

• Repair and Exchange: Due to the specialized nature of this module, repair and exchange services are available from industrial electronics repair specialists.

• Documentation: For definitive technical specifications, refer to ABB's official SYNCHROTACT and UNITROL system documentation for your specific application.

FAQ

Q1: What is the primary function of the ABB UN 0950a-P VAR.1 module?

A: It is a Frequency Matcher Module used in ABB SYNCHROTACT 3 and UNITROL systems. Its primary function is to preprocess the generator terminal frequency signal and feed it to the AVR regulation loop for frequency matching during synchronization .

Q2: What is the difference between UN 0950a-P and UN 0950a-P VAR.1?

A: The "VAR.1" designation indicates a specific hardware revision variant. The base model number identifies the module type, while the variant suffix indicates compatibility with defined system configurations .

Q3: What does the alternate part number HEIR445976R1 refer to?

A: HEIR445976R1 (also written as HEIR445976R0001) is an internal ABB ordering or reference number for this specific module variant . It may be used interchangeably with UN 0950a-P VAR.1 when sourcing the component.

Q4: Is this module still in production?

A: This is a legacy component. The UNITROL 500/1000 series is in its end-of-life phase, with ABB promoting UNITROL 1020 as the replacement. However, the new 1020 platform uses a different architecture with no direct upgrade path for legacy UN-series boards—existing systems rely on spare parts for continued operation .

Q5: How can I verify compatibility with my SYNCHROTACT or UNITROL system?

A: Consult your system documentation or contact ABB technical support with your specific system model and serial number. The VAR.1 designation indicates compatibility with particular hardware revisions. Pay close attention to revision compatibility (R1/V1 vs. older R0/V0) as mixing revisions may cause system errors .

Q6: Can this module be repaired?

A: Yes. Industrial electronics repair specialists offer repair and exchange services for the UN 0950a-P module. Completed repairs typically include a warranty (varies by provider).