NA 1: UL 508A: Industrial Control Panels in USA

Professional Training for Industrial Control Panels with destination USA

Last edit: 03/02/2024

Training objective

TARGET GROUP: Electrical department of machinery manufacturers.

SCOPE: The aim of the course is the design of Electrical Control panels of machinery with destination the USA. The training has a good introduction to the approach of Electrical Safety in USA and in Canada and will focus on the USA standard for Industrial Control Panels: UL 508A: The standard for the design, construction and certification of Industrial Control Panels of machinery in USA. We are member of the Standard Technical Panel.


Professional training on USA regulations for electrical panels of machinery.

DURATION: 16 hours


MODULE 1 (8 hours)

  • Machinery Safety: a comparison between Europe and North America on the applicable standards
  • The Authority Having Jurisdiction (AHJ)
  • Product Certification
  • Electrical Distribution Systems in North America
  • Max allowed Voltage Drop
  • Distribution systems in USA and Canada
  • The neutral conductor in USA and Canada
  • Product Certifications
  • Listed and Recognised
  • Branch and Feeder Circuits
  • FLA, FLC and Branch vs Feeder
  • Combination Starter Types
  • The Circuit Breakers
  • Components suitable for the Feeder circuits
  • Types of Circuit Breakers
  • The use of Supplementary Protectors in USA and Canada
  • The Short Circuit
  • The Arc Flash
  • The Electrical Label
  • The warning signs
  • Cable Colours
  • Nema 250: Enclosures for Electrical Equipment
  • Distances in front of Control Panels
  • International Panel Shop Program and ref standards
  • Scope of UL 508A and C22.2 N°286
  • Wire Bending space
  • ANSI certification and its implications
  • Terminal Temperature Limitations
  • Minimum required spacings in branch and control circuits
  • Section 10: Spacing in Branch and Feeder circuits
  • Use of components in the Feeder part of the panel

MODULE 2 (8 hours)

  • Power Circuits: Branch
  • Section 29: Cable assembly inside ICP
  • Section 28: Expected Field Cable assembly
  • Section 30: Disconnect Switches
  • Section 31: Branch Circuit sizinf and Protection
  • The Tap Conductors
  • Power Circuits: Feeder
  • Machine Supply Circuit and Disconnecting Means
  • Excepted Circuits
  • Protection from Direct Contacts
  • Obligation to de-energise the panel
  • How to size a feeder circuit
  • Sizing of the feeder protection: Section. 32
  • Sizing of the Contactor: Section 33
  • Example
  • Example of suitable components
  • Component characteristics
  • Control Circuits
  • Bonding – Size of Terminal or Bonding Conductor
  • Transformer and Power Supply Secondary Grounding
  • Identification of Grounding and Grounded Circuit Conductors and Terminals
  • Enclosures and Accessibility of Live Parts
  • Ventilation Openings
  • Bonding
  • Wire Bending Space
  • Enclosure Environmental Control Devices
  • Power Circuits: Components Type, Sizing, Conductor requirements
  • Circuit breaking: Component Type, Sizing, Setting
  • Combination Motor Controller: Sizing of Motor, Heating loads and Lights
  • Feeder Circuits: Components type and Sizing
  • Power Transformers: Components type and Sizing
  • Control Circuits: Components type and sizing; Low-Voltage Limited Energy Circuits
  • Components and Panels Marking
  • Industrial Control Panels
  • Calculation of SCCR (Short Circuit Current Rating)
  • Component breaking capacity
  • UL 508A: devices limiting available short circuit current
  • Contactors in feeder
  • Examples


GT Engineering is Member of the UL Standard Technical Panel (STP) for UL 508A; Principal (Special Expert) on the NFPA 79 Technical Committee; Member of WG 4-006 of the CE Code (Canadian Electrical Code C22.1); Member of the ANSI writing subcommittees for B11.0, B11.19, B11.26.