In article ,
John Davis wrote:
On 12/9/2011 1:37 AM, Bill Horne wrote:
On 12/8/2011 5:36 AM, David Ryeburn wrote:
This evening I checked the blog of VK1OD, which is always interesting.
The most recent posting there is "A medium priced generator set from
eBay". Worth reading.
http://www.vk1od.net/hardware/genset/index.htm
Another example of getting what you pay for.
Thanks for the link. One part caught my eye:
"Since this generator will be used with multiple appliances
of Class II, the neutral was bonded to the earth conductor
to allow the effective use of a portable RCD device."
... and I'm curious why that would be necessary. Of course, the author
is using 240 Volt, 50 Hz power, but I thought everyone kept neutral and
ground leads separate.
73,
Bill, W1AC
By code Neutral and Ground are bonded in the main service entrance box.
I have heard folks tell of portable generators where that is supposed to
"Cause Problems" however any portable generator or fixed generator
designed to supply power to a stick-build house.. Has got to be able to
deal with that.. Since many times a Generator transfer switch (Every one
I've seen) leaves neutral and ground bonded, and in fact cross
connected.. Only the "HOT" (L-1, L-2) Leads are switched.
Actually, the NEC is very jumbled about exactly how this is supposed to
be setup. Mast Electrical Inspectors, and MANY Electrical Engineers,
still do NOT understand this area of the NEC as Published and Amended,
and it still isn't well understood, even with all the changes and
enhancements over then last TWO Decades. There are TWO basic Definitions
that MUST be understood BEFORE one can effectively communicate, about
the Neutral/Ground Bonding, REQUIREMENTS of the NEC.
1. Separately Derived Power Source
2. Portable Power Source
Once those are understood, then one can have a conversation about how
each can be connected to a Grid Tied Electrical Distribution System,
using a NEC REQUIRED and Approved Power Transfer System.
This section of the NEC is a relatively late addition to the Code, and
mostly was ignored before the Y2K Upgrades for Backup Power Systems. Now
with the number of Backup Power systems installations growing
exponentially, it is getting some PLAY, in the Inspection, and
Engineering, ends of the electrical world. there are some really good
explanations published over in the Generator and Motor Forums on
www.smokstak.com, as well as a good bunch of Resident SmartGuys, that
have MAN-Years of Professional Experience, in the Backup Power
Generation field. Just say'en.... This is NOT for the uninitiated, as
even many of those folks that should know and understand this stuff,
clearly do NOT.... YMMV....
--
Bruce in Alaska add path before the @ for email