HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
REGISTER   |   LOGIN   |   HELP
Blogs
Sherlock Ohms

These Fuses Melt in Water

NO RATINGS
< Previous Page 2 / 2
View Comments: Oldest First|Newest First|Threaded View
<<  <  Page 4/4
skyefire
User Rank
Gold
Re: A Bug between a Relay
skyefire   10/29/2012 1:17:27 PM
NO RATINGS
Never had a *bug* in my AC unit, but I did have a relay in the outdoor compressor unit fail several times.  The relay was an unsealed, open type, which was located near the bottom of the unit.  Since the housing of the unit was open at the bottom, the relay was (mostly) protected from rain, but any time we had to mow the grass or weed-whack the growth around the compressor, clippings would be driven with enough force to "hook" up under the lip of the housing and hit the relay, carrying enough moisture to eventually cause corrosion.  Ditto for snow during the winter.  The first time that relay failed, it jammed *closed*, and kept the compressor running constantly for *weeks*.  We didn't notice b/c the compressor was a quiet type, and the central air blower inside the house only activated when the thermostat ordered it (and I was working very long hours).  I first noticed something odd when i had to enter the crawlspace and found the high-pressure coolant line was dripping condensation over its entire length constantly, even when the central air wasn't running.  Ended up tracking down the culprit by killing the thermostat power circuit and realizing that the compressor kept running.  The relay was only $20, and I replaced it myself easily enough, but good grief, the electric bill for that month was ENORMOUS.

That relay became the "first check" item whenever there was an AC problem for the next several years.  It never jammed closed again, but it did fail a few more times. Why anyone would use a relay with mechanical components open to the elements in an installation like that is beyond me.

GuidoBee
User Rank
Iron
Re: A Bug between a Relay
GuidoBee   11/1/2012 7:14:34 PM
NO RATINGS
the link at the bottom of mr bandit's post can be inspirational to those folks who don't want to be told what they cannot do.  Adm Grace Murray Hopper is one of my heroes (heroine?).  Just to add a bit to the linked info, Adm Hopper was interviewed on 60 minutes, was a regular on the lecture circuits (no pun intended) and is the namesake of the Computing center building at the Naval Air Station at North Island (San Diego), CA in addition to the (Navy) combatant ship named after her. 

I think she serves as a great example to anyone considering a career in technologies or computers, but especially for young ladies and girls who wonder if they can become leaders in high tech areas (may not be so much doubt about that now), but it was the likes of Amazing Grace who led the way 65  years ago. 

CDR, USN, RET

<<  <  Page 4/4
Partner Zone
More Blogs from Sherlock Ohms
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
The problem with the engine light was not the usual sort. Only Sherlock Ohms could chase down the real problem.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Design News Webinar Series
3/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
2/27/2014 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
12/18/2013 Available On Demand
11/20/2013 Available On Demand
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Apr 21 - 25, Creating & Testing Your First RTOS Application Using MQX
SEMESTERS: 1  |  2  |  3  |  4  |  5


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: April 29 - Day 1
Sponsored by maxon precision motors
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service