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220V vs 120V - Any benefit?

jstang said:
Any one have a link for freeware signal generator that can produce a good 20hz Square wave? I rather use a real signal generator as don't trust my lap top audio out.....

jk
Click to expand...

I wouldn't use square waves for audio test signals, it's extremely hard on speakers - especially high frequency drivers.
 
MudPuppy176 said:
This is not so. If both 120V circuits are equally loaded the voltage drop is identical as the wire length is essentially halved. No tap changes, no cord cap (plug) changes, no 240V receptacle, just standard 20A receptacles useful for ANYTHING at any future time. Your amp was shipped with a 120V plug because its more than adequate.
Click to expand...

Mud, I'm not following you on this wire length thing.


As to the circuit itself...

What I'd probably do is to use a 3-wire shared neutral circuit and wire it into two quad boxes so there would be 2 duplex receptacles on each leg of the circuit in each quad box.

Then, one could use them either as 120V receptacles and balance the loads across the two circuits. Or, get tricky and make up a "Y" harness that would use standard plugs to go into two outlets on opposite 120V legs. Then, the single end of the "Y" harness would provide the 240V.
 
Hehehehehe ..... Sorry but 220 has less voltage drop because Ohms law..... and P=IE.... the current path is always the same length for both 120 and 220...Which means the wire length is same and the resistance is the same for each example below...

Shall we....

Lets assume the Power consumed is the same....1000 Watts and the Wiring is the same giving .5 Ohms total Loop back to the breaker box ... Lets us 240Vs and 120Vs....

Power = E ( Voltage ) x I ( Current )
For 240V...

P = 1000Ws
1000 = 240 * I What is I?
I = 1000 / 240 = 4.166 amps.

For 120V....

P = 1000Ws
1000 = 120 * I What is I?
I = 1000w / 120 = 8.333 amps.

Now to resolve for the voltage drop across the .5 ohm wire resistance.

Ohms law I = E/R
For given I and given R find the E (V)

I x R = E(V) or the drop across the total wire loop back to the breaker box...

For 240V
4.166 amp x .5 = 2.08 volts of Drop....

For 120V
8.333 amps x .5 = 4.16 volts of Drop...

For the same Power, same wire size, same distance from the breaker box .... 240 will always drop HALF the voltage as 120....

Now if we do it on a percentage basis.... THE PRECENT DROP FOR THE EXAMPLE ABOVE....

2.08 / 240 = .86 %

4.14 /120 = 3.46 %

This percentage directly affects the +/- rail voltage of an unregulated supply like almost every Vintage SS amp has....


Now I just completed the 220V circuit install and used 10 gauge wire back to breaker box. Compared to the 14 gauge in indirect circuit ( test 1 ) and 12 gauge direct washer drier circuit ( test 2 ) .... the 10 gauge will provide even less V drop.....

I know you don't believe the math above .... such is life.... Buy any reasonable book on household wiring and you will find the same discussion in it...

On to reconfiguring the AMP....

johnk





MudPuppy176 said:
This is not so. If both 120V circuits are equally loaded the voltage drop is identical as the wire length is essentially halved. No tap changes, no cord cap (plug) changes, no 240V receptacle, just standard 20A receptacles useful for ANYTHING at any future time. Your amp was shipped with a 120V plug because its more than adequate.
Click to expand...
 
The higher the supply voltage, the less that is lost through the conductor (P=I²R for losses, V²/R, higher voltage = less current while maintaining the same power transfer). Otherwise those big power lines running through the countryside would not be charged to 150,000V.
 
whoaru99 said:
Mud, I'm not following you on this wire length thing.


As to the circuit itself...

What I'd probably do is to use a 3-wire shared neutral circuit and wire it into two quad boxes so there would be 2 duplex receptacles on each leg of the circuit in each quad box.

Then, one could use them either as 120V receptacles and balance the loads across the two circuits. Or, get tricky and make up a "Y" harness that would use standard plugs to go into two outlets on opposite 120V legs. Then, the single end of the "Y" harness would provide the 240V.
Click to expand...


I was thinking about the Y and to legs .... But then I started to scare myself.... :) ..... Because the wire I used is a 3+plus ground.

See what happens when I do something that is non-standard.... It's me that gets tripped up by it.... Cause 5 years from I will forget about what I did.....

jk
 
I assumed you'd get lost. By using two 120V circuits, there is no neutral load, so that conductor's resistance is lost. You're left with two hots, same as 240V. Double the current, halve the conductors= same loss. With 240V you use both conductors back to the panel necessarily. Two 120V circuits provide the same power as a 240V circuit. The wire (neutral) is still there but carries no load. I'm sure I explained that poorly.
 
EchoWars said:
The higher the supply voltage, the less that is lost through the conductor (P=I²R for losses, V²/R, higher voltage = less current while maintaining the same power transfer). Otherwise those big power lines running through the countryside would not be charged to 150,000V.
Click to expand...

150KV is almost distribution. I've switched 345 and 765KV, EXCITING!
 
jstang said:
Hehehehehe ..... Sorry but 220 has less voltage drop because Ohms law..... and P=IE.... the current path is always the same length for both 120 and 220...Which means the wire length is same and the resistance is the same for each example below...

Shall we....

Lets assume the Power consumed is the same....1000 Watts and the Wiring is the same giving .5 Ohms total Loop back to the breaker box ... Lets us 240Vs and 120Vs....

Power = E ( Voltage ) x I ( Current )
For 240V...

P = 1000Ws
1000 = 240 * I What is I?
I = 1000 / 240 = 4.166 amps.

For 120V....

P = 1000Ws
1000 = 120 * I What is I?
I = 1000w / 120 = 8.333 amps.

Now to resolve for the voltage drop across the .5 ohm wire resistance.

Ohms law I = E/R
For given I and given R find the E (V)

I x R = E(V) or the drop across the total wire loop back to the breaker box...

For 240V
4.166 amp x .5 = 2.08 volts of Drop....

For 120V
8.333 amps x .5 = 4.16 volts of Drop...

For the same Power, same wire size, same distance from the breaker box .... 240 will always drop HALF the voltage as 120....

Now if we do it on a percentage basis.... THE PRECENT DROP FOR THE EXAMPLE ABOVE....

2.08 / 240 = .86 %

4.14 /120 = 3.46 %

This percentage directly affects the +/- rail voltage of an unregulated supply like almost every Vintage SS amp has....


Now I just completed the 220V circuit install and used 10 gauge wire back to breaker box. Compared to the 14 gauge in indirect circuit ( test 1 ) and 12 gauge direct washer drier circuit ( test 2 ) .... the 10 gauge will provide even less V drop.....

I know you don't believe the math above .... such is life.... Buy any reasonable book on household wiring and you will find the same discussion in it...

On to reconfiguring the AMP....

johnk
Click to expand...

I'm an electrician, a Home Cheapo book I don't need. I'm trying to help you. Trust me, I know what I'm doing. I'm more than aware of Ohm's law, you're simply misapplying it. You're not the first engineer I've corrected.
 
Sorry that is not correct.... with 120V or 220v there are only 2 conductors passing current.....same number of conductors....same resistive drop.

Even if you spread the across two 120v circuits in of one 220.... WHICH I CAN NOT SEEING I AM SPEAKING ABOUT ONE AMP....the drop percentage wise is still greater for Each circuit....

Now even for the Service side out at the Poll all of this hold true....

Oh by the way where you are making the mistake is in thinking that you have DOUBLE THE CURRENT.... WRONG....for the same power delivery the current is halved on 220 vs 120. Which is why Higher voltage is more efficient for long haul....

I guess you are aware of Ohms law .... But never understood P=IE.....

You're not really an electrician...NOW ARE YOU.....

jk



MudPuppy176 said:
I assumed you'd get lost. By using two 120V circuits, there is no neutral load, so that conductor's resistance is lost. You're left with two hots, same as 240V. Double the current, halve the conductors= same loss. With 240V you use both conductors back to the panel necessarily. Two 120V circuits provide the same power as a 240V circuit. The wire (neutral) is still there but carries no load. I'm sure I explained that poorly.
Click to expand...
 
MudPuppy176 said:
I'm an electrician, a Home Cheapo book I don't need. I'm trying to help you. Trust me, I know what I'm doing. I'm more than aware of Ohm's law, you're simply misapplying it. You're not the first engineer I've corrected.
Click to expand...

Show the details..... which you have not.... You would not be the first electrician, ( which I just corrected you on not understanding P=IE ) nor the last electrician I will correct....

I really doubt you are an electrician.... While I have debated items with a lot of different people including my electrician brothers... I have yet to find an Electrician that DOES NOT UNDERSTAND P=IE.....and does not understand that 220 is more efficient.

Nope ..... You fail the sniff test.....


Show me the details.....

jk
 
Back on track... The Marantz manual has an error on the conversion steps but does show it correctly in a diagram....

jk
 
jstang said:
Show the details..... which you have not.... You would not be the first electrician or last electrician I have corrected....


Show the details.....

jk
Click to expand...

Simple (for an electrician) hard (for an engineer). A balanced 120V 3 wire circuit has no neutral load (following me so far?). A 240V circuit has two current carrying wires to the panel, twice the loss. There and back, as in two wires necessary for 240V. Two 120V circuits essentially use the same two wires (hots) plus a shared neutral, which when balanced carry NO current therefore no voltage drop. Same power delivered, same voltage drop, half the voltage, more useful. As the mismatch between legs increases, there will be current (and voltage drop) across the neutral. Hence my claim to halve the wire length as one wire carries no current.
 
Hehhehehe, this fun....

Forget the words Neutral or hot...they are confusing you. Because what is connected to the AMP's transformer is just two wires....For 120 its two wires...for 220 its TWO WIRES STILL......

Simply think in terms of two wires carrying current....not three wires....

Current Flows in those two wires regardless of 220 or 120..... so the number of wires carrying current to amp has not changed... But the Voltage is being raised from 120 to 220.... and the power consumed is the same at that amp....


Raise the Voltage, the current will drop proportionally for the same POWER being consumed by the amp..... Less current equals less voltage drop voltage drop across the AC wiring....

Its that simple...you are confusing yourself with the number of wires.....



jk
 
Ok just sorted this out the Text in the manual wrong....but the diagram is correct....


jstang said:
Back on track... The Marantz manual has an error on the conversion steps but does show it correctly in a diagram....

jk
Click to expand...
 
I may be new @ this but from what I have read earlier in other posts (read australia/europe) was that in those countries the 240vac is carried on ONE current line and one neutral (please correct me if I'm wrong), I think that would be a more efficient power delivery to an amp than 2 120vac lines. I dont know if the 240vac input on your model is setup for 2 120vac lines or a single 240vac. I may be wrong but it think it'd be bad to connect the 2 phases together of our 240vac (a short perhaps?) here in can/usa. I think europe/australias 240vac is wired like our 110/120vac if i read it right.. that could cause issues perhaps... one single 240 vac hot vs 2 120 vac hots(aka dryer plug) ... different to me on a basic level.
Regards.
A.
 
Ok it is up and running first listening impressions....

So first few songs.... ITS WELL WORTH THE 78$ and then much more....no need for an expensive power conditioner...

Now I made a huge leap....from a 15amp 120 over 14 gauge to 220 20amp over 10gauge... I did test it on 120 20amp Direct line but was only a little improve over the 15 amp line...


But detailing is improved...
First strike of drum can be startling...
Transient response seem greatly improved....
Bass more control and deeper...

And the Meter lamps are brighter & are not dimming with heavy bass passages.... I think I might be dimming my neighbors lights now.... :)

Detailed rail testing to come later... I am soaking up the sounds for now.....

Your MPG may vary.....

johnk
 
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