[Wind Chaser]

I want to bypass my amplifiers "internal SMPS" with an external regulated DC power supply through the IEC.

First - The anatomy of a power cord - a black lead, a white lead and a green lead...



Not sure if I have this right; but to those that know, please correct me if I am wrong...

Black = Live?
White = Neutral?
Green = Ground/Earth?


Second - Polarity going in...



Again, please correct me if I am wrong...

Left pin = Neutral?
Middle pin = Earth?
Right pin = Live?


Third - The other side of the IEC...



The top black lead is attached to the earth symbol on the far right of the SMPS - see below
The next black lead (above the red lead) is attached below the N on the SMPS - see below
The red lead on the bottom is attached below the L on the SMPS - see below





Fourth - As previously stated, I want to bypass the SMPS.



The above red and black leads on the amps board were removed from the SMPS.
I want to be sure that they are attached correctly (for obvious reasons) to the IEC.

[Folsom]

Do you have an ohmeter? You can check everything with one.

But yes,

Black = hot
White = neutral
Green = safety ground

Still a good idea to check. I've had a cord wired incorrectly from someone else before.

[Wind Chaser]

Unfortunately, I don't. 

[srb]

It doesn't sound like a stellar idea to perform your proposed modification yet still use the IEC receptacle for external power supply connection.  What happens if someone else connects an AC power cord to the IEC connector that will be directly wired to the amplifier board?

Also, I wouldn't attempt any DIY projects without a multimeter.  Even an inexpensive one will be adequate for the majority of tasks. http://www.rakuten.com/prod/etekcity-digital-lcd-voltmeter-ammeter-ohmmeter-multimeter-volt-ac-dc/247985203.html#

Steve

[Speedskater]

Serviceable ohmmeters are available for has little as $4 US. They are Digital Multi Meters (DMM). While the low budget meters don't have as many ranges and functions nor do the cover the full audio frequency range, they will answer most questions.

[randytsuch]

It doesn't sound like a stellar idea to perform your proposed modification yet still use the IEC receptacle for external power supply connection.  What happens if someone else connects an AC power cord to the IEC connector that will be directly wired to the amplifier board?

Also, I wouldn't attempt any DIY projects without a multimeter.  Even an inexpensive one will be adequate for the majority of tasks. http://www.rakuten.com/prod/etekcity-digital-lcd-voltmeter-ammeter-ohmmeter-multimeter-volt-ac-dc/247985203.html#

Steve

+1

I would add a DC jack to do this.  You need to drill a hole to add the jack, but it will be safer from accidents.

And if you don't want to drill a hole in the chassis, remove the IEC, replace it with a small, flat piece of metal, and drill a hole in this plate.
HD and other HW stores should carry flat Aluminum or steel plates you could use.  Al is easier to work with.

Oh, and if you want to bypass the internal SMPS, the existing AC wiring really doesn't matter, until you want to reconnect.  For reconnect, I always take pictures of everything, so you can just use the pics when/if you ever want to change it back.

The important wires for you are in the last picture, and it clearly says black is ground and red is +V.

The other thing to consider is does the IEC tie incoming earth ground to the chassis?  You might be able to see directly, but you really need a voltmeter to check this. 

Randy

[Wind Chaser]

What happens if someone else connects an AC power cord to the IEC connector that will be directly wired to the amplifier board?

I thought about that, but that's not going to happen, as no one enters the room, much less touches the gear.

There is a multimeter somewhere in the garage, buried in anyone of 500+ boxes. The consequences of moving. Might have to buy another one.

[Wind Chaser]

I would add a DC jack to do this.

That's the plan, but my impatience requires a more immediate, albeit short term temporary solution. 

[srb]

I thought about that, but that's not going to happen, as no one enters the room, much less touches the gear.

Okay, but what about in the future when you pass on and your wife sells your equipment to someone - who plugs an AC power cord into the IEC connector?  Pa Pow!   

Steve

[Wind Chaser]

My wife?