Why do you need 3 phase? u are not running a bakery biz with full commercial ovens
Are you running all 6 AC at the same time? Even if you are -

-assuming
1hp x 5 unit at 4A each = 20A
1.5hp x 3 unit at 5A each = 15A
That's only 35A.

Still have room for other usage like water heater (15A each); but do note WH one unit eats at least 15A.

The thing is don't run all the WH simultaneously with all 6x AC can already.


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My point is if your existing is already 63A supply, and you haven't encountered the main breaker (without test button) tripping, then maintain as is - no need to change anything. If you're on 40A supply then need to upgrade.

You cannot|must not|pulis kata jangan|anyhow change the fuse|breaker to 80A WITHOUT the associated cable size upgrade.
This is because FUSE burn to protect CABLE. If you simply change the fuse to bigger one without upgrading cable, it become CABLE burn to protect FUSE.
This is a universal statement that applies to all circuits i.e. TNB to TNB fuse to TNB meter to DB box; and from DB box to all the little individual sub-circuits in your house.

The breakers in the DB box are already sized correctly for the existing installation. You can do a like-for-like replacement i.e. 20A to 20A, 6A to 6A, to refresh the DB box if you are worried its too old (>30 years). You cannot change the 6A to become a 20A.

If there is an anticipation in very high total load, it should be possible to either upsize or change to three phase but this will entail expensive cost of laying new cables TNB side w. TNB panel contractor to tarik cables. What I am suggesting here is if there is no real need to upgrade (based on actual load & practicality, whereby you can turn on everything and use a clamp meter to check your actual load amps), it's not worth it.

This post has been edited by ceo684: Apr 7 2024, 01:09 AM