Spike Electric is a leading industrial manufacturer in designing custom, solid-state electrical control panels manufactured by cUL/UL 508A & UL508 standard.

Absence of the control panel plate or plate with incomplete data.Electrical Control Panels Designed To Meet Your Operational Requirements.

Non-compliances regarding the spacing between cables or devices.

In addition to sizing, their use should be considered very carefully because, depending on their certification (UL1077, UL489 and so on), they shall have definite applications in a control panel.

Circuit breakers not compliant to the UL standards or installed in the wrong way.

The main problems that can be encountered while approving Industrial Control Panels in USA are: The sizing of motor startings and of the main protection have different rules from the ones listed in EN 60204-1. However, this is not enough to guarantee that the Industrial Control Panel is compliant to the UL508A. UL508A covers Industrial Control Panels, while for Switchboards (in Europe we would also call them Distribution Panels) UL891 is the reference standard.Д®very component, in order to be used in an Industrial Control Panel, must be approved by UL ('listed' or 'recognised'). The new languange extends the exception, in section 26.1.1,В to Air Conditioners. The control transformer reduces the fault current to a value that willВ not cause any safety issue with the enclosure air conditioner in case a short circuit occurs.

If they do not have one, theyВ must be installed on an isolated secondary of a controlВ transformer. That is the meaning of the statement in 26.1.1 that they ' shall comply with the requirements for general construction and power circuits'.

Air conditioners should be provided with an SCCR.

We are now fully alligned with NFPA 79, articole 12.6.4.2: ' Conductors installed within control enclosures shall not be smaller than 26 AWG'. Now the new note clarifies that wires up to AWG 26 can be used ' for connection of electronic control input/output and control devices'. That 'and' should have been an 'or' in reality. The note stated that wire sizes of 20 to 26 AWG could be used ' only for connection of control circuits for electronic programmable input/output and static control (having no moving parts)'.

It was finally clarified NOTE 'b' in Table 38.1: Ampacities of control circuit conductors.

At the same time, it is alligned with several UL standards that allows the label to be on the inside, like UL 508. Therefore, the standard remains alligned with NFPA 79 that requires Nameplate Data 'shall be attached to the outside of the enclosure'. We finally reached a compromise: the Label (that contains important data like the panel FLC and the Panel SCCR) can be on the inside however, if the panel is for Industrial Machineries, the label much be on the outside.

Since a few years we are discussing whether the Nameplate Data must be on the outside of the panel or it can be on the inside.

For all other Branch Circuit Protective Devices (or BCPD), UL 489 circuit breakers and Fuses in compliance with UL 248 shall be used.

It is made clear that ' Self-protected Combination Motor ControllersВ ' can be used to protectВ motor circuits only.

Hereafter the main changes in requirements On the 13th July 2021 a revision was published. This designation indicates that the standard has been developed under a fair and open process designed to protect the rights and interests of every participant. 3 has been designated as an American National Standard (ANSI). The lastest release of this standard was in April 2018: UL 508A Ed. In Europe, the equivalent standards are EN 61439-2В (for switchboards) and EN 60204-1 (for industrial control panels for Machineries). While the NFPA 79 provides prescriptions for industrial machinery control panels, UL508A has a bruader scope and it is focused on the criteria in order to design the control panel. Starting from the basics of electrical safety, stated by the NEC and looking at the prescriptions stated in NFPA 79, it gives indications for the design of industrial control panels. UL 508A is the technical standard for the Industrial Control Panels in USA.

Ul 508a manual