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  3. 157948-15626

Using 15 amp power conditioner and power cords with 20 amp wired outlet.

I’m thinking of having my electrician run a 20 amp dedicated line in place of the existing household line that is in the living room of my 1959 built house and most likely is ungrounded and part of a string of multiple outlets on the same circuit. 

I know this has probably been covered many times before and, yes I may check the archives for solutions but thought I would inquire here anyway. 

Since I’m going to he trouble of running a dedicated line, I figure I might as well get it to 20 amp specs. In the future I may order a new solid state amp in the 20 amp version for better bass and dynamics. 

For now though, I would continue to use my existing 15 amp power conditioner (Bryston BIT-15) and power cords. As far as I know the power conditioner would protect my components and nothing would malfunction as far as I can tell. Please feel free to educate me here. 

My future 20 amp upgrades would be a new Bryston cubed series amp with a 20 amp option and possibly moving up to the Bryston BIT-20 power conditioner for better bass, quietness and dynamics potentially with my low impedence Thiel CS-3.6 speakers. 

Thanks for any help.
masi61
oldhvymec
5,101 posts
 
The conductors are twisted, but the average proximity of the hot conductor and the neutral conductor with respect to the isolated grounding conductor is not equal. Under load, this will induce a voltage along the length of the isolated ground wire, partially defeating the intent of isolation (see Ground Voltage Induction section of this paper).

This is not good? Right...? Don't you want isolation?

Regards
jea48
4,408 posts
 
This is not good? Right...? Don’t you want isolation?

The problem is the use of 4 conductors in the cable twisted assembly instead of only 3 conductors. Hot, neutral, and equipment grounding, conductor.

Solution.
Armor Clad for Healthcare Facilities (AC-HCF) Aluminum Armor Clad for Healthcare Facilities (AC-HCF) is the best choice for Isolated Ground A/V systems. Like MC, it contains an additional grounding conductor, although with this type of cable it is permissible to use the metal jacket as the safety grounding conductor, as required with isolated ground installations. The biggest benefit is that the average proximity of the hot conductor and the neutral conductor with respect to the isolated equipment grounding conductor is nearly equal, virtually eliminating ground voltage induction (GVI), even on long runs.

Like MC, it contains an additional grounding conductor, although with this type of cable it is permissible to use the metal jacket as the safety grounding conductor, as required with isolated ground installations.
https://info.legrandav.com/l/71782/2018-12-14/7zh25n


"although with this type of cable it is permissible to use the metal jacket as the safety grounding conductor,"

Yeah, but..... There is a bare armor/bond wire that runs the entire length of the cable. The armor/bond wire is used to ground the outlet box and the supporting back strap of the duplex receptacle. The green insulated conductor, that is part of the twisted Hot and neutral conductor assembly, connects to the IG isolated ground terminal screw of the receptacle outlet. Three conductors twisted together. Hot, neutral, and IG equipment grounding conductor.

  • Interlocking aluminum strip
  • Easy to identify green armor

  • Full size green insulated copper grounding conductor plus armor/bond wire combination provides redundant ground or isolated grounding capability
    • https://www.afcweb.com/ac-hcf-armored-cables/hcf-lite-aluminum-health-care-facilities-cable/

    .
    djones51
    4,947 posts
     
    @masi61 
    I'm sure your electrician knows what 3 wire is. I assume he licensed in your area and knows the local codes. I wouldn't worry about all this banter and reading a bunch on wiring unless you want to tackle it yourself. Let the guy or gal do the job and anything you don't understand I imagine they would be happy to explain. 
    Post removed 
    masi61 OP
    97 posts
     
    @jea48 - I’m going to read through the information you provided. I will show it to my electrician. I may have to take notes and write down the names of the types of grounds and the specific cables recommended here in order to get a proper estimate on running a dedicated 20 amp circuit that not only is fully code compliant but also as quiet and with as good of sound quality as possible for my system.
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