Freethought & Rationalism Archive

Ab_Normal · 03-04-2003, 02:40 PM

At my house we have two clocks that run off batteries, the alarm clock, and the clock on the microwave. (VCR is at --:-- because I don't care.) I've noticed lately that the two clocks that run off house current are slowly gaining time when compared to the battery clocks. The battery clocks are still keeping the same time, so I don't think that it's because the batteries are running down. (At least, I think it's highly unlikely that they'd be both running down at the same rate, because the batteries weren't changed at the same time.) The clock on the microwave was reset to match the battery-powered clock in the kitchen on 2/19, and it's already 5 minutes fast.

I don't mind, because it gets my husband out of bed in a more timely manner, but now I'm wondering if I should be worried about my wiring. (Not to mention the consumer electronics plugged into the wiring!) Any ideas?

Mageth · 03-04-2003, 02:51 PM

Naah, you don't need to worry about your wiring or the appliances plugged into it because of this.

The problem with the two fast clocks may be simply internal to the clocks themselves (some clocks even have external adjustors to slow down or speed up the clocks if they aren't accurate). However, it's possible the clocks are sensitive to the frequency (expressed in Hertz, or Hz, which are cycles per second) of your house's AC (alternating current) power supply. House AC supply is typically @50-60Hz, IIRC, but can vary quite a bit. This is not due to your house wiring but to the (external) power grid that supplies your house with AC electricity. And this variation shouldn't cause any problems with your consumer electronics, which are typically constructed to support AC within a range of Hz and voltage (and which often convert the AC supply to DC (direct current) for internal use, anyway). However, certain appliances, such as PCs, may be sensitive to power fluctuations (e.g. spikes or surges), and should always be on a good UL-certified surge/spike protector.

Ab_Normal · 03-04-2003, 03:38 PM

Thanks, Mageth. My house is in an older part of town, so I imagine that's part of the problem. And I have the computer on a good UPS/surge protector. I'll quit worrying about the electrics catching on fire, then!

Shadowy Man · 03-04-2003, 04:10 PM

The poltergeist inhabiting your house doesn't like to be late for work, so he's setting the clocks ahead. However, he only has access to your house's eletrical system, and can't affect battery powered appliances.

Silent Dave · 03-04-2003, 04:25 PM

Unplug your clocks. That way, at least they'll be accurate once per day.

Dave

Shadowy Man · 03-04-2003, 04:26 PM

Quote:

Originally posted by Silent Dave
Unplug your clocks. That way, at least they'll be accurate once per day.

Twice a day if you don't differentiate between AM and PM!!

Ab_Normal · 03-04-2003, 04:40 PM

Quote:

Originally posted by Silent Dave
Unplug your clocks. That way, at least they'll be accurate once per day.

Dave

Oh, that would be marvellous! I don't carry a personal timepiece (I kill them dead)... if I could escape the tyrrany of time keeping, I would be so happy.

Kinross · 03-04-2003, 05:12 PM

Most AC clocks are timed by the AC frequency, either 50 Hz or 60 Hz. Since you are in the US its 60 Hz. If your clock was ment to run on 50 Hz it would run 20% faster. Since your clock is only 5 minutes fast over five days this isn't the problem.

A noisy line can result in erratic behavior. Lamp dimmers and florescent lights on the same circuit can also screw up the timing.

Since its an older home my guess is a noisy line. Nothing to worry about.

03-04-2003, 02:40 PM	#1
Ab_Normal Veteran Member Join Date: Aug 2002 Posts: 2,842	Electricity Question At my house we have two clocks that run off batteries, the alarm clock, and the clock on the microwave. (VCR is at --:-- because I don't care.) I've noticed lately that the two clocks that run off house current are slowly gaining time when compared to the battery clocks. The battery clocks are still keeping the same time, so I don't think that it's because the batteries are running down. (At least, I think it's highly unlikely that they'd be both running down at the same rate, because the batteries weren't changed at the same time.) The clock on the microwave was reset to match the battery-powered clock in the kitchen on 2/19, and it's already 5 minutes fast. I don't mind, because it gets my husband out of bed in a more timely manner, but now I'm wondering if I should be worried about my wiring. (Not to mention the consumer electronics plugged into the wiring!) Any ideas?

Thread Tools	Search this Thread
Show Printable Version	Search this Thread: Advanced Search

03-04-2003, 02:51 PM	#2
Mageth Contributor Join Date: Jul 2001 Location: Deep in the heart of mother-lovin' Texas Posts: 29,689	Naah, you don't need to worry about your wiring or the appliances plugged into it because of this. The problem with the two fast clocks may be simply internal to the clocks themselves (some clocks even have external adjustors to slow down or speed up the clocks if they aren't accurate). However, it's possible the clocks are sensitive to the frequency (expressed in Hertz, or Hz, which are cycles per second) of your house's AC (alternating current) power supply. House AC supply is typically @50-60Hz, IIRC, but can vary quite a bit. This is not due to your house wiring but to the (external) power grid that supplies your house with AC electricity. And this variation shouldn't cause any problems with your consumer electronics, which are typically constructed to support AC within a range of Hz and voltage (and which often convert the AC supply to DC (direct current) for internal use, anyway). However, certain appliances, such as PCs, may be sensitive to power fluctuations (e.g. spikes or surges), and should always be on a good UL-certified surge/spike protector.

03-04-2003, 03:38 PM	#3
Ab_Normal Veteran Member Join Date: Aug 2002 Posts: 2,842	Thanks, Mageth. My house is in an older part of town, so I imagine that's part of the problem. And I have the computer on a good UPS/surge protector. I'll quit worrying about the electrics catching on fire, then!

03-04-2003, 04:10 PM	#4
Shadowy Man Veteran Member Join Date: Jun 2002 Location: A Shadowy Planet Posts: 7,585	The poltergeist inhabiting your house doesn't like to be late for work, so he's setting the clocks ahead. However, he only has access to your house's eletrical system, and can't affect battery powered appliances.

03-04-2003, 04:25 PM	#5
Silent Dave Banned Join Date: Oct 2000 Location: Bloomington, MN Posts: 2,209	Unplug your clocks. That way, at least they'll be accurate once per day. Dave

03-04-2003, 05:12 PM	#8
Kinross Veteran Member Join Date: Sep 2001 Location: . Posts: 1,281	Most AC clocks are timed by the AC frequency, either 50 Hz or 60 Hz. Since you are in the US its 60 Hz. If your clock was ment to run on 50 Hz it would run 20% faster. Since your clock is only 5 minutes fast over five days this isn't the problem. A noisy line can result in erratic behavior. Lamp dimmers and florescent lights on the same circuit can also screw up the timing. Since its an older home my guess is a noisy line. Nothing to worry about.

Freethought & Rationalism Archive

The archives are read only.