Power Distribution and Digital Support
Join experts & peers to learn, share and engage about the key trends of electrical distribution around safety, availability, efficiency and connectivity, as well as power standards & regulations. From design to implementation and operation, let’s discuss how digital and software are transforming your business and your day-to-day work.
Link copied. Please paste this link to share this article on your social media post.
Posted: 2024-07-08 10:44 PM
HVAC equipment doesn't specify min breaker sizes. Only min circuit sizes and max breaker sizes—what are those? The wire should be sized based on the MCA and the breaker based on the MOCP.
Link copied. Please paste this link to share this article on your social media post.
Link copied. Please paste this link to share this article on your social media post.
Posted: 2024-07-10 10:15 PM
The AC might not require the maximum 40A of the type of HVAC unit. It could be a series of and you have a specific model of the series. For this reason, it is important to know the specific model so that you can know how much current is required.
As for the mcb rating, that depends on the wiring. Breakers are designed to protect wiring from overheating. Based on the load (your HVAC unit), the correct wiring should be laid. This comes from the local or regional standards, following a table.
If your specific model only requires 35A, then the current draw on the cable will stop if there is an issue in the unit, causing a higher draw.
The correct way to look at the required breaker is to know the requirement of the load (HVAC unit in your case), the installed cabling data (AWG, length, type of cable) and use the data in the regional standards table (UL/NEC, or IEC or whatever it is if in some other country).
Link copied. Please paste this link to share this article on your social media post.
Link copied. Please paste this link to share this article on your social media post.
Posted: 2024-07-09 11:36 PM
hello @olporr
Could you please give us more details about your question ?
From where are you ?
What are type of product you speak?
Thanks in advansed .
Link copied. Please paste this link to share this article on your social media post.
Link copied. Please paste this link to share this article on your social media post.
Posted: 2024-07-10 10:15 PM
The AC might not require the maximum 40A of the type of HVAC unit. It could be a series of and you have a specific model of the series. For this reason, it is important to know the specific model so that you can know how much current is required.
As for the mcb rating, that depends on the wiring. Breakers are designed to protect wiring from overheating. Based on the load (your HVAC unit), the correct wiring should be laid. This comes from the local or regional standards, following a table.
If your specific model only requires 35A, then the current draw on the cable will stop if there is an issue in the unit, causing a higher draw.
The correct way to look at the required breaker is to know the requirement of the load (HVAC unit in your case), the installed cabling data (AWG, length, type of cable) and use the data in the regional standards table (UL/NEC, or IEC or whatever it is if in some other country).
Link copied. Please paste this link to share this article on your social media post.
Link copied. Please paste this link to share this article on your social media post.
Posted: 2024-07-15 06:28 AM
The Minimum Circuit Ampacity (MCA) determines the wire size, and the Maximum Overcurrent Protection (MOCP) determines the breaker size. Ensure the wire meets MCA requirements and the breaker does not exceed MOCP. If the AC requires a 40A breaker per MCA, install a 40A breaker, not a 35A breaker.
Link copied. Please paste this link to share this article on your social media post.
Create your free account or log in to subscribe to the board - and gain access to more than 10,000+ support articles along with insights from experts and peers.