[Elecraft] Items you think you can depend on

[Mike Maloney]

A line voltage monitor/alarm a very good idea.   Am surprised Dave's KPA500 power transformer core was not humming away at 60hz over excitation before he got it off line?Being retired from a large electric utility substation department, I know LTC  (load tap changer) controls can sometimes fail.   For those on a very rural line it could be an overheadline regulator gone to max steps boost (HV) or buck for low voltage.  Usually these are single phase large auto-transformers with a plus or minus 10% in 16 steps each side of neutral position.  73
Mike AC5P 

    On Monday, September 4, 2017 12:33 PM, Mel Farrer via Elecraft <elecraft at mailman.qth.net> wrote:
 

 Funny you posted this.
I monitor BOTH sides of the 110/220 VAC service and have alarms set to trigger either line >125 or >250 VAC. Being in the country THINGS happen.
Always expect the unusual.
Mel, K6KBE


      From: David Robertson <kd1na363 at gmail.com>
 To: Elecraft <elecraft at mailman.qth.net> 
 Sent: Monday, September 4, 2017 9:39 AM
 Subject: [Elecraft] Items you think you can depend on
  
Everyone,

 Over time we can grow complacent on many service items such as electrical
power, water and other services over time. Well that can be concerning as
many hidden changes can result in damage to your home and equipment.

Late late night I came in to my den and was closing down my ham station
when I notice my fault light on my KPA500 linear was on. I powered it down
and retired for the evening. This morning I powered up the linear (KPA500)
and at once I got a fault light and had a high voltage alert. I powered
down the linear and checked my input line voltage. It was 137 volts RMS! To
be sure it wasn't my imagination I rechecked the voltage with a different
meter with the same result. In checking the 220 volt outlet I measured 274
volts! My linear is set up for 220 volts operation and it was getting over
90 volts HV.

I alerted the neighbors and cut the main breaker to the house. I then
called the power company's service number and reported the problem. A short
time later they called me back and reported that a regulator in the local
sub station had "Stuck" and was reset. In rechecking my line voltage it was
118 volts on the low side and 236 volts on the high side.

In the 12 years we have been at this qth we found that our town's locally
run power company has been very reliable but this experience showed me that
it is not a bad idea to check your line voltage every once in a while.
73

-- 
Dave Robertson KD1NA
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to farrerfolks at yahoo.com


  
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to ac5p at sbcglobal.net