You're asking about a common point of confusion regarding PLTC cable and its use in Class 1 Division 2 locations. Here's a breakdown

The Core Issue:

501.10(B)(1)(3) does allow the use of PLTC cable in Class I, Division 2 locations, but only under specific conditions that often lead to the misunderstanding.

Breaking Down 501.10(B)(1)(3)

This section essentially says that in a Class I, Division 2 location, you can use PLTC cable for circuits operating at 30 volts or less and 1000 volt-amperes or less. This corresponds to what the NEC generally considers Class 2 or Class 3 circuits.

Key Considerations and Clarifications



It's About the Circuit, Not the Cable Alone

The rule isn't just about whether the cable itself meets PLTC standards. It's about the electrical characteristics of the

circuit that the cable is carrying. If the circuit operates at or below 30V and 1000VA, then PLTC cable can be used (assuming the cable itself is also appropriately rated for the environment). NEC Chapter 9, Tables 11(A) and 11(B)

You are correct to bring this up. The tables in Chapter 9 provide specific limits for Class 2 and Class 3 power sources and circuits. The voltage and VA limitations are defined in Tables 11(A) and (B). If the circuit parameters fall within these limits, they are considered Class 2 or Class 3 circuits.

Beyond Class 2/3

Even if the CIRCUIT IS NOT Class 2 or 3, PLTC Cable still

CAN be used to supply Class 2 or 3 circuits that are present within a Class 1 Division 2 Location as long as the the parameters of 501.10(B)(1)(3) are met. PLTC Cable Requirements

The cable must still meet the general requirements for PLTC cable. This means it needs to be: UL Listed as PLTC. Suitable for the environmental conditions (temperature, moisture, chemical exposure). Installed according to Article 725 and any other applicable requirements.

The Intent

The reason for this exception is that Class 2 and Class 3 circuits are considered low-energy circuits and are less likely to cause ignition in a hazardous location. Therefore, using PLTC cable (which is generally less robust than, say, MC or rigid conduit) is considered an acceptable risk if the circuit falls within the Class 2/3 parameters.

Therefore, to directly answer your question

PLTC cable can be used in a Class 1, Division 2 location if either of the following are met:1.

The circuit in question is designed and operated as a Class 2 or Class 3 circuit according to the voltage and VA limits defined in NEC Chapter 9, Tables 11(A) and 11(B) ,and the PLTC cable is suitable for the environment.2. The circuit in question is supplying Class 2 or Class 3 circuits according to the voltage and VA limits defined in NEC Chapter 9, Tables 11(A) and 11(B) , and the PLTC cable is suitable for the environment.

Important Considerations for Practical Application



Documentation

It's crucial to document the circuit design and ensure that it adheres to the Class 2 or Class 3 limits. This is essential for inspection and future maintenance.

Manufacturer's Instructions

Always follow the manufacturer's instructions for the specific PLTC cable being used.*

AHJ Approval

Consult with the local Authority Having Jurisdiction (AHJ) to ensure they agree with your interpretation and application of the code. Hazardous location installations are often scrutinized carefully.

In summary, it's not just about whether the cable is PLTC, but also whether the electrical circuit it's carrying meets the requirements for Class 2 or Class 3 circuits. Flag for review