Electrical Consumption/Parasitic (Phantom Power) Draws. - Page 12 - Canadian TV, Computing and Home Theatre Forums
 1Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes

post #166 of 173 (permalink) Old 2013-06-16, 10:17 PM
 
Join Date: Oct 2008
Location: S.W. Ontario
Posts: 1,032
Quote:
Originally Posted by txv View Post
There are good and bad applications for electronics. Why put electronics into a fan? - mechanical controls work fine.
For the same reason electronics are used everywhere; to make it a throw-away item that can't be repaired by the owner.
oldyellr is offline  
Sponsored Links
Advertisement
 
post #167 of 173 (permalink) Old 2014-05-31, 12:16 PM Thread Starter
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 55,989
I haven't used my UPM Watt Meter much lately because I had done most of my research years ago per post 1 of this thread. Lately I've been monitoring my rechargeable devices again since I wanted to see how much power they drew and whether it made any significant difference if I charged them on or off peak.

Most of these rechargeable devices cost less than a cent to recharge, but I was surprised that my charger for my MacBook Pro used power when it was plugged in, but not charging my computer (totally disconnected). It used 2 Watts when plugged into the wall, but not connected to the computer! I never leave it plugged in, but I was surprised by this because I thought there would only be power use with a "complete circuit", but I guess the "brick" itself has some smarts which use some power. It also uses 2W when the computer is off, but fully charged.

So, if you've got a bunch of 'charging bricks" and you leave them plugged in, some of them may be using power even when they're not charging anything. Easy to check with an inexpensive Watt Meter. It's no big deal, but I thought I'd post...

PS. The UPM Energy Meter only measures down to 2W, so some smaller devices don't even register when charging. My toothbrush doesn't register, probably using only 1W when charging, while my shaver does register because it uses 3-5W. when charging. My eneloop battery charger uses 2W for 2 batteries and 4W for 4 batteries. When 2 of the 4 batteries are charged, it goes down to 2W and the indicator lights show full charge on the two fully charged batteries.

57's Home Theatre (Latest equipment & photos)
57 is offline  
post #168 of 173 (permalink) Old 2014-06-01, 09:24 PM
txv
Veteran
 
Join Date: Oct 2008
Location: Canada
Posts: 1,938
I think it's the primary side (high voltage) of the transformer that consumes power when there's no load. That side is a complete circuit even when something's disconnected, i believe.

Laptop adapter is actually a small switching powersupply rather a straight transformer/rectifier setup.

WARNING: The HVAC information I provide is not based on field experience and DOES NOT constitute professional advice.
txv is offline  
 
post #169 of 173 (permalink) Old 2019-04-02, 02:17 PM Thread Starter
57
Moderator
 
Join Date: May 2002
Location: Toronto, Rogers, 9865 & 8300-eHDD, Sharp LC75N8000U, Denon AVR4310Ci; Sony KDL40W3000, 9865
Posts: 55,989
I've recently had to replace my 31 year-old top-loading Maytag washing machine because it started leaking and I wasn't about to have a 31 year old washer repaired... During the 31 years, it never met the Maytag repairman. Our dryer is still working fine and I can probably repair it myself if the belt or element fail.

I purchased a "compact" front loader by LG (WM1388HW) because today's full size units are way too large for the space we have. Since there are only two of us, we don't create a lot of laundry. We probably do laundry about 3X per week in electrical off-peak hours and we probably won't need to do any more loads with the slightly smaller front loader.

Although the front loader uses about 0.070 kWh per load, instead of 0.150 kWh for the old machine, it has a 3W parasitic load while the old washer used zero Watts when off. This means that the new washer actually uses more standby power than usage power.... I realize I could get a switch to turn it off if I wanted to.

It does use less than half the water, so that will save us about $50/year. It varies the amount of water used depending on the load. It also leaves the clothes much drier after the spin, so our dryer doesn't run as long, probably saving us another $30/year. We wash in "tap-cold" water. (The "cold" setting on these fancy front loaders actually mixes in hot water to bring the water to about 20C. We may use this occasionally if we have really soiled items, but so far tap-cold works fine, which is what we used on the old washer)

I've updated post 1 of this thread for kWh & Watts, but some of the $ numbers may still be old (outdated) numbers from when I started the thread.
Jake likes this.

57's Home Theatre (Latest equipment & photos)
57 is offline  
post #170 of 173 (permalink) Old 2019-04-28, 08:44 PM
 
Join Date: Mar 2006
Location: Port Stanley, ON
Posts: 503
Quote:
Originally Posted by txv View Post
I think it's the primary side (high voltage) of the transformer that consumes power when there's no load. That side is a complete circuit even when something's disconnected, i believe.
I have the same issue with the charger for my cordless drill batteries. When the charger is plugged in, with no battery on charge, you can feel a slight warmth on the underside of the charger. So I know that this charging unit is consuming power even when I do not have a battery in it. So I leave it unplugged until I need it.

Delhi SFA 1483, Antennacraft Suburban VHF, CM7778
Gentleman is offline  
post #171 of 173 (permalink) Old 2019-04-28, 09:57 PM
Veteran
 
Join Date: Jun 2011
Location: 43° N, 81.2° W
Posts: 7,776
Almost everything electronic uses a switching power supply these days. There will always be a small parasitic draw and the power supply will typically be between 70% and 85% efficient when providing power. The power supply is kept active to supply power for on/off switching and other sensing operations. For example, a battery charger will need power to sense the presence of a battery.

Electronically operated appliances and devices need power to sense when the on/off switch is pressed or other actions occur. Some require power to provide logic for safety interlocks. TVs and other remote controlled devices need power to sense remote control on/off commands. Computers need power to sense when wake up actions occur such as a power button press, WOL, keyboard key press, mouse movement, scheduled software events, etc. A lot of this was once done with mechanical switches that actually disconnected the power but those are becoming less common due to "smart" devices that rely on microprocessor control.
ExDilbert is offline  
post #172 of 173 (permalink) Old 2019-04-29, 08:05 AM
 
Join Date: Mar 2006
Location: Port Stanley, ON
Posts: 503
I should have mentioned my cordless drill charger is a linear supply and if you hold the base to your ear, you can hear the 60 Hz hum from the transformer inside.

I'm surprised that in this day, manufacturers are still making linear supplies.

Delhi SFA 1483, Antennacraft Suburban VHF, CM7778
Gentleman is offline  
post #173 of 173 (permalink) Old 2019-04-29, 01:14 PM
Veteran
 
Join Date: Jun 2011
Location: 43° N, 81.2° W
Posts: 7,776
Switching power supplies also have transformers but they are much smaller and lighter.
ExDilbert is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Canadian TV, Computing and Home Theatre Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome