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Dedicated Lines - 32 amps possible?

I no electrical expert and am planning to install 2 dedicated lines (220v, 32amps) each. Is this possible or overkill since almost everyone else is using 20 amps.

Here is my scenario:

Line 1 :
- Installed JPS AC power in wall cable (80 ft) from panel and will be used for power amps only.
- incoming power is 230v 63 amps, electrician already installed a separate MCB, ELCB, and i have the choice of installing either a 20 or 32 amp Type C breaker. This is seperate from the main box, he tapped the power out to the separate box.
- this line will run to an isolator near the equipment (basically it is a big ON/OFF switch). At this Isolator, this will split going into 2 x Duplex Furutech Gold Receptacles...
- amps used are McCormack 225 monoblocks and possibly Earthquake Grand Cinenova 5 channel...This amp has a 4kva trans inside which the dealer says, tends to trip breakers due to high current draw during start up..thus the 32 amp question...
- simplistic thought...since this line will split into 2 outlets, if all three amps are on, will the current draw be high enough to warrant the 32 amps or will 20 amps be enough..

Line 2:
- this is just normal Romex wire which is 6mm dia each (I think this is either 12 or 10 guage)...
- this is also running from the separate box that is installed...I have the option of either putting a 20 amp or 32 amp Type C breaker....
- this will also go to a separate Isolator that will go into a Furutech duplex receptacle...
- this outlet will be for the Hydra 8 that will connect the CD, DVD and Pre-amp....

Both lines are running together and because of the plastic trunking, there is a plastic separator between the cables....

So, should I go to 20 amp breakers or 32 amps...

Thanks for your advice.
teck5
teck5 OP
47 posts
 
Hi Everyone,
Thanks for the responses so far...Some of the codes may not apply as I am not in the US.

Jea48: i live in Singapore.

Basically the JPS cables are 10 Guage and my "Romex" type cable is also in the same range. These cables are able to take 32 amps....

So am i on the right track on should I just stick to 20 amps...

Thanks for the advice.
jea48
2,944 posts
 
Grand Cinenova 5 channel...This amp has a 4kva trans inside which the dealer says, tends to trip breakers due to high current draw during start up..thus the 32 amp


4000 va divide by 230V = 17.39 amps. That amp should have its own dedicated circuit. That is if the amp will be on at the same time as the other amps. And with that said I doubt a 20 amp breaker would withstand the initial inrush current if the primary of the transformer does not have a soft start circuit.

Code in Singapore, I have no idea. In the US the largest breaker that could be installed on a branch circuit feeding a NEMA 5-15R duplex receptacle or a 5-20R receptacle is 20 amps.

What is the current rating for your receptacle, is it rated for 32 amps?

You really need to direct your questions to the electrician that did the electrical work for you.

teck5 OP
47 posts
 
Hi Jea48,

Thanks for the quick response..

Since I am running a separate box for these 2 lines (note that the main incoming is still 63 amps), my electician says that using 32 amp breakers are okay...this is also okay with our code since all is dependent on the incoming power. Please take a look at the link below...it has photos of the install...hope i downloaded it correctly..

http://pg.photos.yahoo.com/ph/tkchia5/album?.dir=873fscd&.src=ph&store=&prodid=&.done=http%3a//photos.yahoo.com/ph//my_photos

He has installed Isolators near the receptacles, which is a big ON/OFF switch (which has and earth line), this will then run into the US style duplex outlets (115v 20amp)...see link below...a check with Furutech, say's that 230v 20 amps running through is not a problem...

As you can see from the photos....he has not terminated them to the furutechs as I am waiting for them to come...

http://www.furutech.com/produ_2.asp?ProdNo=73

As for the Earthquake amp, please take a look at the specs below...THis amp will be an add on later... have not yet decided to buy it...so if it proves to be too much that I will look for a less demanding amp...

http://www.earthquakesound.com/cng_5.htm

Hope this info helps....Thanks again...
jea48
2,944 posts
 
He has installed Isolators near the receptacles, which is a big ON/OFF switch (which has and earth line), this will then run into the US style duplex outlets (115v 20amp)...see link below...a check with Furutech, say's that 230v 20 amps running through is not a problem...


this will then run into the US style duplex outlets (115v 20amp)...see link below...a check with Furutech, say's that 230v 20 amps running through is not a problem.

If I understand you correctly, Furutech told you that you could use a US NEMA 5-20R receptacle for 230V is that correct? Maybe in Singapore but not in the US.
The NEMA 5-20R can only be used on a nominal 120V 20 amp branch circuit. Never to be used on 230V, connected to a 20 or 32 amp breaker.

Maximum power that can be connected to a NEMA 5-20R receptacle:
120V X 20 amps = 2400va (residential family dwelling unit). 1920va commercial/industrial applications.

Here is what you will have if you follow what Furutech has proposed,
230V X 20 amps = 4600va. Granted the power amp would never normally draw that much power. But what if??
another example,
230V connected to a 32 amp breaker. 230V X 32A = 7360va

I notice from the picture of the amp it has an IEC male connector for a detachable power cord. Why not just buy a cord that will fit the configuration of a 230V 32 amp, or higher, rated receptacle for Singapore?

I was not able to bring up your second link.
teck5 OP
47 posts
 
Hi Jea48,

Let me check on your suggestions with the electrician...I see what you are saying....and the last thing I want to do is to mess things up...

My approach has been:
- make sure that the incoming lines are separate from the main box...with separate breakers....this is done....
- make sure that the amp line and other components line are separate...this is done....
- make sure there is enough juice....thus the 32 amps...this is done ....but realise through your questions that the receptacles may not be rated for this (esp at 32 amps)

I will check with Furutech again....just to be doubly sure..

Could you please try clicking the 2nd link again...I tried it and I was able to go through....the second link is to the furutech page...
http://www.furutech.com/produ_2.asp?ProdNo=73

Let me get back to you on this...Thanks again....
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