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From: "Peter Forbes" <>
Date: Fri, 21 Jan 2005 11:45:42 +1100
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Interesting discussion points made by respondents regarding grounding, 3 wire 
extension leads and use of GFIs.

BE AWARE that not all setups can achieve this.

IN PARTICULAR, the HONDA series of generators, EU10i, EU20i, EU26i, which are 
used extensively worldwide do not have the neutral tied to earth.

If you measure between Active and Neutral you will achieve the rated voltage  
(110 or 240), but Active to Earth or Neutral to Earth will give half the rated 
voltage in both cases.

There is an earth point on the generator (which should have an earth stake 
attached for safety and RFI purposes), but this means that MOST GFI's will NOT 
WORK in this situation, regardless of where they are placed in the layout.

This leads to a common (and dangerous) trick that operators will often do and 
that is to break the earth wire connection to eliminate any residual common 
mode RFI travelling from the generator along the earth wire.

The BETTER method is to make up a short extension lead (approximately 80 cm) 
with as many turns wound through ferrite toroids to eliminate RFI and plug this 
into the generator with the station extension leads plugging into this short 
extension lead.

WE have found 3 toroids in series to present sufficient impedance to be useful 
from 1.8 mhz upwards.

Most of the commercial filters available, do not filter the earth lead and in 
fact, often suggest the use of a dummy adaptor with the earth connection 
removed.  This is a dangerous practice in the field day situation.


Peter   VK3QI   (IOTA ops  VI3JPI, VI5WCP and VI5BR)


See:  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

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