Who's rewired their house for this hobby?
Chuck Guzis
cclist at sydex.com
Sun Nov 23 16:44:16 CST 2014
On 11/23/2014 01:15 PM, Holm Tiffe wrote:
.
> but sine you already have 240V outlets, it should be possible to change the
> distribution slowly to 3 phase power.. it's a matter of time and the only
> needed thing for compatibility are the transformers with modified
> secondaries.
"Low hanging fruit".
Most commercial office and retail buildings already have 3-phase
supplies because of installed HVAC electrical needs. I wouldn't mind
that--the heat pump on my house has to have the compressor and fan motor
capacitors checked annually because they do degrade with time. I just
replaced the 135 uF 330VAC start capacitor on the compressor--it has two
capacitors; a 135-160 uF start and a 40 uF run as well as a starting
relay--modern Chinese capacitors do not deliver the life that old
PCB-containing oil ones did. If the compressor instead used a 3-phase
motor, none of that would be necessary. The last starting cap simply
blew its top, even though it's a vented unit and only 3 years old.
But if you'd ask any utilities manager why not move to 3-phase
residential distribution, you'd get the response that residential
distribution was, in fact, 3 phase--one phase per household.
To answer Tony's question about power tools, almost all hand/portable
power tools are rated for 15A or less. My router (Bosch, if it
matters), claims a rating of 3 hp and maximum current of 15A at 120V.
Yes, I know that 3 hp is about 2200W and therefore almost 19A at 120V.
Such is the nonsense that goes for nameplate ratings in the US. Vacuum
cleaners are rated at the motor's "locked rotor" current draw, as
another example.
Large power tools, such as a floor sander or table saw are often 240V
units, meaning special wiring and outlets.
Wasn't the UK slow to standardize on receptacles and plugs? I seem to
recall a mention that some appliances long ago were supplied without
plugs altogether; the customer was supposed to install whatever was
suitable.
--Chuck
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