Option 2 listed class 2 power supply is easier to achieve than option 4 limited power circuit acc.
Class 3 power limited circuit cable.
A class 1 circuit is the portion of the wiring system between the load side of the overcurrent protection device ocpd or the power limited supply and the connected load.
These circuits are designated class 1 2 and 3 not to be confused with the class i ii and iii hazardous locations an entirely different matter.
Ul 13 standard for safety for power limited circuit cables which lists 30 awg as the smallest for class 2 and 24 awg for class 3.
Listed information technology equipment.
Equipment listed as a class 2 or class 3 power source amplifier for audio program signals.
But remember most class 2 or 3 circuits usually are wired using listed cable types specified by the nec.
This article will help distinguish the differences between these circuits.
The power supply connected to a class 1 2 or 3 circuit for the most part determines the class of that circuit.
Nec class 2 i max limits versus ul60950 limited power circuits 0v 5v 10v 15v 20v 25v 30v 35v 40v 45v 50v 55v 60v 65v.
A listed class 2 or class 3 transformer.
Equipment supplying class 2 or 3 circuits must be marked to indicate each circuit that is a class 2 or 3 circuit 725 42.
The following graph shows a comparison of nec class 2 i max limits with ul 60950 limited power circuit requirements.
725 41 the power source for a class 2 or a class 3 circuit must be one of the following.
May be installed in raceways conduit cable trays and.
Also can be used in security and audio applications.
For example class 1 power limited circuits are supplied by a power supply with an output that does not exceed 30 volts and 1 000 volt amps.
Remember that the class 2 or 3 circuit begins at the power supply.
Mini split wire is a class 3 power limited circuit cable used with hvac mini split systems.
The minimum size circuit is 18 awg when a class 2 or 3 circuit is reclassified and used as a class 1 circuit.
For example heating system thermostats are commonly class 2 systems and the majority of small bell buzzer and annunciator systems are class 2 circuits.
Also class 1 remote control circuits are limited up to 600 volts with no other.
That means conductors and equipment on the supply side of the class 2 or 3 power source must be installed in accordance with chapters 1 through 4 725 51.
Mini split tray cable 600 volt.
The limited power and voltage of these circuits is what makes them a separate and specialized wiring method.
A listed class 2 or class 3 power supply.
