| |
Subject |
Author |
Date Posted |
Forum
|
 |
RE: Furnace pops breaker after 30 seconds.
If it is a 120VAC breaker then it may be due to the increased load from the converter. The converter converts 120VAC to 12 VDC. 12VDC then powers the furnace.
Maybe the 120VAC 15 Amp breaker supplies power to something else along with the converter.
|
Harvard
|
06/13/19 01:04pm |
Tech Issues
|
|
RE: Wireless Mouse Jitters Resolution
It is a Dell Laptop with a USB wireless mouse and an onboard touch pad. Yes one is RF but the touch pad is hardwired. What ever, the touch pad is the source of the jitters, I think.
|
Harvard
|
06/10/19 02:42pm |
Technology Corner
|
|
Wireless Mouse Jitters Resolution
The reason why my wireless mouse had the jitters was because I had a mechanical pencil sitting on the touch pad. Go figure. :)
|
Harvard
|
06/10/19 01:14pm |
Technology Corner
|
|
RE: A home electrical question...
Drawing of wnjjs Stray Capacitance
https://i.imgur.com/bBAH19Rl.png
|
Harvard
|
06/05/19 09:38pm |
Tech Issues
|
|
RE: A home electrical question...
Quote from Health Canada on the topic of Electric Magnetic Fields (EMFs):
START QUOTE:
EMFs are invisible forces that surround electrical equipment, power cords, and wires that carry electricity, including outdoor power lines.
•Electric Fields: These are formed whenever a wire is plugged into an outlet, even when the appliance is not turned on. The higher the voltage, the stronger the electric field.
•Magnetic Fields: These are formed when electric current is flowing within a device or wire. The greater the current, the stronger the magnetic field.
EMFs can occur separately or together. For example, when you plug the power cord for a lamp into a wall socket, it creates an electric field along the cord. When you turn the lamp on, the flow of current through the cord creates a magnetic field. Meanwhile, the electric field is still present.
END QUOTE:
The physics of Capacitance is related to Electric Fields.
The physics of Inductance is related to Magnetic Fields.
|
Harvard
|
06/05/19 08:38pm |
Tech Issues
|
|
RE: A home electrical question...
I can see stray capacitance between hot conductors conducting enough leakage current to make a LED light glow in the dark.
|
Harvard
|
06/05/19 07:33pm |
Tech Issues
|
|
RE: Electrical Issue
Switching Mode Power Supplies and GFCIs
START QUOTE:
As explained earlier, RF noise filtration circuits in SMPS (Switching Mode Power Supply) generate intentional Earth Leakage Current. SMPS are used extensively as DC power sources in modern day electrical / electronic devices e.g. Audio / Video / Computing devices, power supplies, battery chargers etc. A single GFCI outlet / GFCI breaker may be serving multiple SMPS loads and therefore, will be sensing the sum of all the Earth Leakage Currents and, if the sum is > 4 to 6mA after connecting this unit, the GFCI will trip.
END QUOTE:
|
Harvard
|
06/03/19 04:02pm |
Class C Motorhomes
|
|
RE: why does one arm of the awning stick?
sometimes mine will do that. just grab the arm handle and lift a little. should release. works everytime for me.
Tim
X2....the top of the arms sit in a channel, you need to lift the arm to clear the channel then pull the top away from the RV.
|
Harvard
|
06/01/19 06:31pm |
Tech Issues
|
|
RE: Beware of 15/30A Hockey Puck Adaptors
Best modification anyone can do with that style of adapter.......chuck it in a trash can!
Trust me, it was trashed AFTER a 2 hour drive to find a dog bone version.
|
Harvard
|
05/30/19 10:08am |
Tech Issues
|
|
Beware of 15/30A Hockey Puck Adaptors
The 15/30 Amp adaptor shown in the picture was responsible for an Open Ground/Hot Skin episode.
The picture was taken AFTER it was modified to fix the problem.
The modification was to take slip joint pliers and crimp the female ground which exposed the female electrode visible in the picture.
Note, I expected to see an electrode on each side of the female BUT only one electrode is visible.
I believe having only one electrode was the problem of not making contact in the first place.
https://i.imgur.com/jjIidvBl.jpg
|
Harvard
|
05/30/19 08:58am |
Tech Issues
|
|
RE: getting schocked by door/electrical issue urgent
These "hockey puck" 15/30 Amps adaptors are a typical source of open grounds.
The round female ground does not make electrical contact with the male counterpart.
Notice in the picture the electrode of the female ground is visible only because it has been crimped to fix the problem.
https://i.imgur.com/jjIidvBl.jpg
|
Harvard
|
05/30/19 07:55am |
Class C Motorhomes
|
|
RE: getting schocked by door/electrical issue urgent
So, summarizing the Hot Skin problem:
First, the door is electrically connected to the Chassis AND the Chassis is NOT grounded to the pedestal ground wire.
The outside Hot Skin where the RV is connected to shore power BUT having an open ground allows the RV Chassis (on rubber tires) to float above Earth potential. Due to the capacitance between H and G and the capacitance between G and N the chassis will float at a VAC of about 120/2 = 60 VAC OR LESS to Earth.
The OR LESS is there because there could be capacitive coupling (or a resistive path) between the Chassis and Earth that would tend to reduce the float VAC to EARTH.
If the Chassis to Earth voltage exceeds 60 VAC then there is ALSO a resistive leakage path from Hot To Chassis... DANGER...this is a lot more then a tingle.
When we are inside a properly grounded RV our bodies are likewise floating unless we are touching a conductive path to Chassis Ground. Our floating bodies act as capacitive plates and are exposed to 60Hz Electric Fields. The coupling strength of these EFs to our bodies vary in intensity. They vary in intensity by virtue of the body's proximity to hot wires and the effective area of exposure. At no point is the inside Body to Hot coupling as strong as the inside Body to Chassis coupling so the body floats at relatively low voltages.
For Example: Strange "Hot Skin" Electrical Issue - Getting minor Shocks
|
Harvard
|
05/29/19 09:09pm |
Class C Motorhomes
|
|
RE: Camper Backwashing Power Into Vehicle
Research the functionality of a "BIRD" module. It is used to have the vehicle battery and the RV battery live together.
BIRD Module
|
Harvard
|
05/26/19 03:09pm |
Tech Issues
|
|
RE: Electricity and electric and magnetic fields (EMFs)
I have often wondered about whether or not 3 phase Electric Fields would cancel out. Appears not to be the case.
3 Phase Electric Fields
|
Harvard
|
05/24/19 09:06am |
Tech Issues
|
|
RE: Tiny Soldering "gun"?
USB yet, you will be able to solder without powering the device down. :)
|
Harvard
|
05/23/19 01:09pm |
Tech Issues
|
|
RE: Strange "Hot Skin" Electrical Issue - Getting minor Shocks
Having an AV pacemaker, I am careful about circuitry. Most non contact voltage sensors will alert around 30 volts. This is a very quick and easy way to detect and then stop alerting when efforts and being made to null the improper voltage.
Looks like we need to read the small print.
The run of the mill non contact voltage sensor appears to detect a Magnetic Field.
Seems the non contact voltage sensor that detects an Electric Field is not so common.
Non-contact Voltage Measurement Based on Electric-Field
Effect
On Edit: If it only detects a magnetic field, there needs to be current in the wire.
Where as, an electric field is present any time the wire is hot, current or not.
|
Harvard
|
05/18/19 02:14pm |
Tech Issues
|
|
RE: Strange "Hot Skin" Electrical Issue - Getting minor Shocks
So, summarizing, here is where I THINK (as in theory) we are at:
The outside Hot Skin where the RV is connected to shore power BUT having an open ground allows the RV Chassis (on rubber tires) to float above Earth potential. Due to the capacitance between H and G and the capacitance between G and N the chassis will float at a VAC of about 120/2 = 60 VAC OR LESS to Earth.
The OR LESS is there because there could be capacitive coupling (or a resistive path) between the Chassis and Earth that would tend to reduce the float VAC to EARTH.
When we are inside a properly grounded RV our bodies are likewise floating unless we are touching a conductive path to Chassis Ground. Our floating bodies act as capacitive plates and are exposed to 60Hz Electric Fields. The coupling strength of these EFs to our bodies vary in intensity. They vary in intensity by virtue of the body's proximity to hot wires and the effective area of exposure. At no point is the inside Body to Hot coupling as strong as the inside Body to Chassis coupling so the body floats at relatively low voltages.
JMO
|
Harvard
|
05/18/19 10:51am |
Tech Issues
|
|
RE: Strange "Hot Skin" Electrical Issue - Getting minor Shocks
Sorry, I am neither an electrician nor an engineer. I picked up on electronics via the ARRL Handbook. I was at the point where I needed help in explaining something that I knew little about.
So, in retrospect I should have said: "It is time for the electricians OR the engineers to chime in...." and the offer still stands. :)
|
Harvard
|
05/18/19 09:52am |
Tech Issues
|
|
RE: Strange "Hot Skin" Electrical Issue - Getting minor Shocks
Hi All -
....
Any more testing ideas ?
....
As a test: Install a temporary conductor in reach of your hand (while sitting in the offending seat) from an "independent" Chassis ground point.
Does the tingle come and go when you hold and not hold this test ground conductor?
If so, as a fix: Cover the exposed metal frame with non conductive tape.
(No, I do not think duct tape is non conductive.)
On Edit: The idea being, it is the body that is not grounded.
|
Harvard
|
05/18/19 08:54am |
Tech Issues
|
|
RE: Electricity and electric and magnetic fields (EMFs)
Neat stuff, had no idea DC transmission has been around since the 1970s..
So I do have some knowledge of the Magnetic Field around a DC circuit.
BUT, nothing about a DC Electric Field, or so I thought....
Then Dr Google says this:
"DC Electric Field: DC Electric Fields, can be referred to as an Electrostatic Charge present on an object"
Now that I understand.
|
Harvard
|
05/17/19 07:03pm |
Tech Issues
|
