power consumption question

[tony.silveira]

hi guys,

new to the board, please be gentle

i'm setting up a home theatre / game room with lots of equipment. i'm getting some quotes from electricians to pull in two or three 20 amp circuits into the room. in the meantime, i did have a question on power consumption (watts and amps being drawn) from my audio equipment. can anyone help me calculate draws for the following?

-- onkyo 626 receiver
-- nht superones, original 100 watts from 1996 (5 total)
-- klipsch r-12sw

from documentation, the receiver says 580 watts, the speakers rated at 100 (500 total) and the sub rated at 400. that's a total of 1,480 watts. is that right? if I'm only pulling 1,800 from a 120v outlet, that seems like a LOT for just the audio equipment. throw in a 65 inch LG C1 OLED (347 watts) and a next gen console (200 watts), wouldn't I plow a circuit? and if online calculators are accurate, the amps being drawn are W/V=amps? So...

-- receiver -- 4.83 amps
-- speakers -- 4.16 amps
-- sub -- 3.33 amps

that's 12.32 amps from a 15 amp circuit!

apologies for the newbie question, i'm really trying to make the room safe with all that's in there.

thanks so much for any input!

 

[TLS Guy]

hi guys,

new to the board, please be gentle

i'm setting up a home theatre / game room with lots of equipment. i'm getting some quotes from electricians to pull in two or three 20 amp circuits into the room. in the meantime, i did have a question on power consumption (watts and amps being drawn) from my audio equipment. can anyone help me calculate draws for the following?

-- onkyo 626 receiver
-- nht superones, original 100 watts from 1996 (5 total)
-- klipsch r-12sw

from documentation, the receiver says 580 watts, the speakers rated at 100 (500 total) and the sub rated at 400. that's a total of 1,480 watts. is that right? if I'm only pulling 1,800 from a 120v outlet, that seems like a LOT for just the audio equipment. throw in a 65 inch LG C1 OLED (347 watts) and a next gen console (200 watts), wouldn't I plow a circuit? and if online calculators are accurate, the amps being drawn are W/V=amps? So...

-- receiver -- 4.83 amps
-- speakers -- 4.16 amps
-- sub -- 3.33 amps

that's 12.32 amps from a 15 amp circuit!

apologies for the newbie question, i'm really trying to make the room safe with all that's in there.

thanks so much for any input!

The speakers are not going to take any power over an above the receiver, as the receiver powers the speakers except the sub. The max power draw of your receiver is 6.2 amps. I would guess that your estimate of the sub power draw is correct.

You likely have other units, like players and TV. The TV will have significant power draw.

However the item you did not allow for is in rush current on turn on. If you do not have enough reserve you will trip the breakers at turn on.

To be on the safe side, I would put in a couple of 15 amp circuits to cover future expansion. If the electrician suggests a couple of 20 amp circuits, I would not argue.

Even so my power amps in rush current, I had to install special magnetic shunt breakers, to stop the breakers tripping on turn on.

It is much wiser to have too much power, that not enough available when building out an HT room.

 

[TLS Guy]

I am also having the same issue.

Then the answer is the same.

 

[SithZedi]

As an additional consideration (and expense) I would look into something like this as well. We have "dirty" electricity in my area along with it being prone to lighting strike surges. Maybe its overkill but would rather have that not.

Panamax MR4000

Power line conditioner and surge protector

www.crutchfield.com

 

[-Jim-]

Hi Tony,

As a certified Electrician your question is very common. Folks forget that often, especially in older homes, multiple rooms can be fed from the same 15 amp breaker. (It all depends on local / national electric codes just how many lights and plugs are allowed. Here they allow 12 receptacles per branch circuit but recommend about 8. ) And therefore many people forget to include these devices outside the area of concern, and their loads, when calculating the circuit draw.

Your focus should be on the amps pulled by each device, and electric codes typically allow for in-rush surges in the breaker specs. And forget about Wattage claims. Keep it simple and just add up the amps. Most of the time they are found on the rear of the device or in the manual. Most electrical codes require some devices to have a dedicated circuit - like Microwaves, Fridges, dishwashers, etc., but not so specific in other areas.

If you had a dedicated feed just to your games room a single 15 amp feed could suffice. Sometimes Breakers if old will trip prematurely (usually on inrush at start up) and those should be replaced.

I hope this is helpful.

 

[highfigh]

hi guys,

new to the board, please be gentle

i'm setting up a home theatre / game room with lots of equipment. i'm getting some quotes from electricians to pull in two or three 20 amp circuits into the room. in the meantime, i did have a question on power consumption (watts and amps being drawn) from my audio equipment. can anyone help me calculate draws for the following?

-- onkyo 626 receiver
-- nht superones, original 100 watts from 1996 (5 total)
-- klipsch r-12sw

from documentation, the receiver says 580 watts, the speakers rated at 100 (500 total) and the sub rated at 400. that's a total of 1,480 watts. is that right? if I'm only pulling 1,800 from a 120v outlet, that seems like a LOT for just the audio equipment. throw in a 65 inch LG C1 OLED (347 watts) and a next gen console (200 watts), wouldn't I plow a circuit? and if online calculators are accurate, the amps being drawn are W/V=amps? So...

-- receiver -- 4.83 amps
-- speakers -- 4.16 amps
-- sub -- 3.33 amps

that's 12.32 amps from a 15 amp circuit!

apologies for the newbie question, i'm really trying to make the room safe with all that's in there.

thanks so much for any input!

You can deal with the inrush current if you use some kind of universal remote than allows delays between commands. That way, it's not stressing the breaker(s). Your system shouldn't draw more than a 15A circuit can handle but you need to realize that 1800W is 15A and qualify as "only".

Most equipment doesn't cause a large inrush current- the power amplifiers in an AVR don't turn on at the same time as the rest of it since the protection circuit delays their turn on, source devices draw little and your speakers don't draw any current from the electrical service unless they have their own power amplifiers and those NHT speakers don't, so you can knock off that 4.16A from your calculation.

I have installed much larger systems that didn't cause any problems for the breakers and many of those have been operating for over ten years without any problems.

 

[highfigh]

As an additional consideration (and expense) I would look into something like this as well. We have "dirty" electricity in my area along with it being prone to lighting strike surges. Maybe its overkill but would rather have that not.

Panamax MR4000

Power line conditioner and surge protector

www.crutchfield.com

I don't worry about dirty power as much as surges and brownouts. I have an MR4000 and the main reason I bought it is because it shuts off below 90VAC and above 140VAC, which is a far tighter range than many- some do nothing with low voltage and only shut off when the surge reaches 200VAC or 300VAC. I'm not going to expose my equipment to that if it has a regular power cord- if it has a regulated wall wart, I don't worry as much but I still want protection. My Panamax has shut down my AV system and I didn't see any lights flicker- that's fast.

 

[highfigh]

I am also having the same issue.

Those power numbers are worst case, not in typical operation.

 

[highfigh]

The speakers are not going to take any power over an above the receiver, as the receiver powers the speakers except the sub. The max power draw of your receiver is 6.2 amps. I would guess that your estimate of the sub power draw is correct.

You likely have other units, like players and TV. The TV will have significant power draw.

However the item you did not allow for is in rush current on turn on. If you do not have enough reserve you will trip the breakers at turn on.

To be on the safe side, I would put in a couple of 15 amp circuits to cover future expansion. If the electrician suggests a couple of 20 amp circuits, I would not argue.

Even so my power amps in rush current, I had to install special magnetic shunt breakers, to stop the breakers tripping on turn on.

It is much wiser to have too much power, that not enough available when building out an HT room.

Why didn't you find a way to sequence the turn on of the equipment?

 

[TLS Guy]

Why didn't you find a way to sequence the turn on of the equipment?

Because that is gratuitous complication.

I can quite easily turn the five rocker switches on my power amp control unit one at a time. I just go down the row of rocker switches. It is easy and fool proof.
Also my amp case is beefy enough that it requires 24 volt and not 12 volt relays.

Putting in magnetic shunt breakers was just a few minute job. I believe in the "keep it simple stupid, mantra,". This falls well in that category.

The fact is the system is simple, stable and no inconvenience at all.

 

[lovinthehd]

For your gear I think you're overthinking things. If you want max capacity for higher output gear down the line perhaps 20A circuits could be useful, and if it doesn't cost more for the work you're having done, I'd do it. I just wouldn't want to pay for additional work for that kind of load in the first place, as it is negligible.

 

[PENG]

For your gear I think you're overthinking things. If you want max capacity for higher output gear down the line perhaps 20A circuits could be useful, and if it doesn't cost more for the work you're having done, I'd do it. I just wouldn't want to pay for additional work for that kind of load in the first place, as it is negligible.

Agreed, people also often worry about inrush current for nothing. If an amp is going to risk tripping a 15 A breaker, the manufacturer would have said so. If the amp manufacturer suggest the need for a dedicated 15 A breaker, then one can be sure that's what it would need, though 20 A is always better for future proofing even if not needed. Electrician's labor rate is relatively high among the trades, 14 AWG vs 12 AWG wires make little difference.

 

[BMXTRIX]

It is certainly the case that if you are paying for someone to pull a 14AWG cable for a 15amp circuit, then there is ZERO reason not to pay them to pull 12AWG cable for a 20amp circuit instead.

250 feet of 12/2 Romex is currently $152 at Home Depot.
250 feet of 14/2 Romex is currently $114 at Home Depot.

So, $38 cost difference. Maybe a few bucks more for the 20amp breakers vs. 15amp models.

Not sure how long the run is, but I would expect that to be the price difference overall. About $50 or so, and well worth it.

The reality is that a single 20amp circuit should be able to drive everything you have with plenty to spare for years to come. I run my 85" television, theater, a ton of amplifiers, and other gear, off of a single 20amp circuit and I've never had it fail. Your Onkyo, even with 'in rush' current, actually should be well under a few amps at all times during normal use, and likely will max out with heavy listening near 6 amps. That's a lot of power left on the table.

I will likely add a second 20 amp circuit to my setup at some point, but for nearly 10 years, that single connection has done just fine.

 

[PENG]

Just fyi, transformer inrush current when unmitigated would last for a few to may be 10 cycles so residential branch circuit breaker should rarely trip if sized properly. High power amps that don't have any mitigating device, especially those with large toroidal transformer (that's perhaps one of the "cons" of toroidal Tx) will increase the chance of tripping the breaker occasionally when all the stars are aligned, such as being turned on when the incoming sine wave is at 0 V, and with most everything else fed by the same circuit are already running. Again, typically not an issue if a dedicated breaker is used for such large power amps.

 

[tony.silveira]

wow guys, thank you SO VERY much for all of the input!!!

It isn't just the video/audio i'm concerned with. It's a game room also with multiple arcade 1up machines, classic game systems, current gen systems, digital pinball, etc. if i listed everything i have in that room, it would probably throw up red flags to you all!

here is how it's currently wired:

i have my main power strip with the most used items plugged into it and that power strip is ON, BUT, not everything on the strip is powered on. as an example, I have an XBOX series X and a PS5 plugged into that strip. But i would never have both systems on at one.

second power strip has all of classic game systems plugged into it along with all of the little "mini" consoles I have. again, I would never turn on more than one of these consoles at once. This strip is kept OFF unless i go to use it. actually, it's plugged into a smart outlet so I can tell Alexa to turn it on. turn on the strip then turn on the system I am going to play (all others remain off)

third power strip has all of my partycade arcade machines and my digital pinball, also plugged into an alexa smart switch. these all turn ON when the power switch is turned on. these draw a combined total of 2.1 amps (.3 amps each) plus whatever the pinball machine draws (I did buy a meter so i need to test it and log what it pulls)

my main arcade machine, which has a mini fridge in it, is plugged directly into the wall.

so it's a bit of a balancing act...

if I have all my partycades on, then i probably should keep my receiver off if someone wants to be playing a game on the big screen on the xbox/ps5...

if i have my main arcade machine on with the partycades, i probably want to have the tv / receiver / consoles off...

i need to get those lines pulled up into the room so i can forget about this stuff thankfully, the room wall upstairs is the same wall downstairs that the circuit breaker panel is on so it should hopefully be a straight pull up (i'm OK with the additional plugs being all on the same wall).

anyone have any electrician contacts in the SF Bay Area?

 

[BMXTRIX]

here is how it's currently wired:

....

so it's a bit of a balancing act...

If you don't currently have everything plugged into a single wall outlet at this time, are you 100% sure they are all on the same circuit?

It's important to realize that many homes have wiring that appears to be chaotic and stupid, but in reality, the electrician may have wired half the outlets in a room on one circuit, then ran it off to another room for a few outlets there. Then the other half of the room is on another circuit. This helps with load balancing, and you may have two circuits currently available to you already.

So, turn off the breakers in your electrical panel one at a time and see if all the outlets in the room are on a single breaker. You may have more power available than you think you do.

Still, I would just call up a local electrician, if you aren't comfortable with adding a circuit yourself. With a straight shot, it may take a good guy a couple of hours to handle. Be aware that if the electrical panel isn't fully accessible, there will be some holes that likely need to be made. If you are mechanically inclined, adding a circuit is scary, but really easy to do. TONS of YouTube videos on how to do it.

 

[highfigh]

wow guys, thank you SO VERY much for all of the input!!!

It isn't just the video/audio i'm concerned with. It's a game room also with multiple arcade 1up machines, classic game systems, current gen systems, digital pinball, etc. if i listed everything i have in that room, it would probably throw up red flags to you all!

here is how it's currently wired:

i have my main power strip with the most used items plugged into it and that power strip is ON, BUT, not everything on the strip is powered on. as an example, I have an XBOX series X and a PS5 plugged into that strip. But i would never have both systems on at one.

second power strip has all of classic game systems plugged into it along with all of the little "mini" consoles I have. again, I would never turn on more than one of these consoles at once. This strip is kept OFF unless i go to use it. actually, it's plugged into a smart outlet so I can tell Alexa to turn it on. turn on the strip then turn on the system I am going to play (all others remain off)

third power strip has all of my partycade arcade machines and my digital pinball, also plugged into an alexa smart switch. these all turn ON when the power switch is turned on. these draw a combined total of 2.1 amps (.3 amps each) plus whatever the pinball machine draws (I did buy a meter so i need to test it and log what it pulls)

my main arcade machine, which has a mini fridge in it, is plugged directly into the wall.

so it's a bit of a balancing act...

if I have all my partycades on, then i probably should keep my receiver off if someone wants to be playing a game on the big screen on the xbox/ps5...

if i have my main arcade machine on with the partycades, i probably want to have the tv / receiver / consoles off...

i need to get those lines pulled up into the room so i can forget about this stuff thankfully, the room wall upstairs is the same wall downstairs that the circuit breaker panel is on so it should hopefully be a straight pull up (i'm OK with the additional plugs being all on the same wall).

anyone have any electrician contacts in the SF Bay Area?

Now that we know you have arcade games well as AV, you need to know that if those machines are old, you really need to do something to kill the voltage spikes from the solenoids that operate the flippers and anything that kicks the ball out of a hole.

 

[tony.silveira]

thanks guys!

It's a digital pinball machine, PC inside, 4K screen.

 

[tony.silveira]

good news! one of the plugs in the room is on a different circuit, shared with the guest room next door which is rarely used.

so i have safely connected my arcade 1up machines, my digital pinball and my main meme cabinet to that outlet.

all in, that equipment is drawing about 12 amps.

 

[Am_P]

As an additional consideration (and expense) I would look into something like this as well. We have "dirty" electricity in my area along with it being prone to lighting strike surges. Maybe its overkill but would rather have that not.

Panamax MR4000

Power line conditioner and surge protector

www.crutchfield.com

You could benefit more from some gonzo true floating isolation transformer designs out there....