FUSE Question...Very Confused Please Help !

@rocky1313

Use a 250V rated fuse per the fuse holder as stated. 250V/5A

#2. AC 110: S5A... 110 is the AC Line voltage setting for the Amp when the wall outlet mains voltage is 110V - 120V. (S5A 250V fuse.)

Are you sure the fuse is a S5A? Using Google I could not find a S5A 250v fuse.

5A = 5 Amps.

S = ? Slow blow?

@rocky1313

From page 6 of owner manual:

V

S

– Mains Voltage Switch (12)

VOLTAGE SELECTOR

The Penta 5.1 amplifier can be used in all

countries and is good both for 110/115 and

220/230 V. Before the first operation, please

make sure that Mains Voltage Switch is set to

the value accepted in your country.

rocky 1313 said:

#1. AC 230:S2.5A

#2. AC 110: S5A

I have it set to #2 setting ....AC 110 : S5A .......... Correct for US.

Owner manual specs: 500VA Max power consumption.

500VA / 110V = 4.55A. The designer of the amp only bumped the fuse up 110%.

4.55A X 110% = 5A. A 5A slow blow fuse seems a little tight to me for the amplifier...

500VA / 230V = 2.18A X 110% = 2.4A (Round up to 2.5A.)

(500VA / 120V = 4.17A X 120% = 5A)

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@ieales 

The amplifier is designed in Germany.  EU has 230V AC mains power. As stated the amplifier is made to be fed by 230V or 110V. The odd thing, at least to me, is the 110V mains feed. Not sure how the designer arrived at 110/230V.

Usually for a dual primary voltage power transformer there are two primary windings. Example 115V/230V.

The specs for the amp says it has a Max 500VA power consumption. If we assume the 500VA, is for the power transformer VA rating for the AC mains rated voltage(s), then each of the two primary windings are rated for 250VA at 115V each.

For 115V mains feed the two windings are wired in a parallel.

(2 paralleled 250VA windings = 500VA / 115V = 4.35A) 

For 230V mains the windings are wired in series.

(250VA + 250VA = 500VA / 230V = 2.2A.

Just a word about the amp's 250V fuse holder. Because the amp is designed to be fed from 230V mains the minimum fuse holder than can be used is the standard size 250V. So beings the same fuse holder is used also for 110V then naturally the fuse would have to be a 250 volt fuse to fit the fuse holder properly. 

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