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🖥️ActiveHome Pro => ActiveHome Pro General => Help & Troubleshooting => Topic started by: jfaska on September 15, 2009, 07:40:14 PM

Title: clock running fast
Post by: jfaska on September 15, 2009, 07:40:14 PM
I uprgaded to Active Home pro at the begining of the summer and all was going well.
I had been using the older software/hardware since 2000.

Suddenly the clock in my module cm-15 is running fast.

Support suggested pulling the batteries and reseting the device.
I did that and it ran "OK" from sunday to some time over the weekend picking up a minute every day or two.
(I added a nightly event so I can see what time it is, cause AHP won't tell me what time the interface thinks it is)

THe clock was OK on Friday night, but by Monday night I found that it was 30 minutes fast.

I just cleared the memory (via the program) and reset the clock.

Tonight it was 15 minutes fast again.

Any sugesstions?

Thank You
Thanks
Title: Re: clock running fast
Post by: murphy on September 15, 2009, 08:49:16 PM
The clock is based on the 60 Hz line frequency.  You have something in your house that is injecting noise of sufficient amplitude and frequency to make the clock run fast.
Title: Re: clock running fast
Post by: jfaska on September 15, 2009, 09:10:03 PM
thanks, two questions

1 - How do I figure out what?

2 - Why did it work fine for a month or so (and why does the amount of noise/drift seem to be variable)?
Title: Re: clock running fast
Post by: MANOWAR© on September 15, 2009, 09:39:18 PM
thanks, two questions

1 - How do I figure out what?

2 - Why did it work fine for a month or so (and why does the amount of noise/drift seem to be variable)?

What have you added in the last month that takes power? Finding it is as simple as unplugging all the new stuff then adding it back one piece at a time until it shows up again, then put a filter on that item or if it's like a cell phone charger use a plug strip for it.
Title: Re: clock running fast
Post by: tjosan on September 17, 2009, 11:19:12 AM
The clock is based on the 60 Hz line frequency.  You have something in your house that is injecting noise of sufficient amplitude and frequency to make the clock run fast.


I'm not so sure that will help. I had the same happening to my controller and the only way
to correct the problem was to buy a new controller. The old one ran for about a year or so
without any problem and suddenly it started to add minutes. I could reset it, but after a few
days it was back to the old behaviour.
Title: Re: clock running fast
Post by: Dan Lawrence on September 17, 2009, 11:39:52 AM
You are incorrect.  What was posted by : MANOWAR©  was the correct thing to do.  There are so many electronic devices that make noise and can alter the electric power frequency slightly.  The biggest noise producers are cell phone chargers and number one is the PC, desktop and laptop.
Title: Re: clock running fast
Post by: dave w on September 17, 2009, 12:22:14 PM
You are incorrect.  What was posted by : MANOWAR©  was the correct thing to do. 
Maybe not. tjosan corrected his time problem by replacing the CM15A, which points to a problem other than line noise, otherwise the new unit would likely exhibit the same problem. The CM15A uses a crystal clock which could be drifting.
Title: Re: clock running fast
Post by: Brian H on September 17, 2009, 01:16:22 PM
The CM15As controller chip. CY7C63723 has an input for a crystal but in the schematics it looks like X10 chose to use the chips internal one that can be calibrated though the USB Port. I wounder if they are getting reset and are out of calibration.
Title: Re: clock running fast
Post by: Alan V on September 17, 2009, 02:13:14 PM
The CM15As controller chip. CY7C63723 has an input for a crystal but in the schematics it looks like X10 chose to use the chips internal one that can be calibrated though the USB Port. I wounder if they are getting reset and are out of calibration.


If the circuit uses zero crossings of the 60Hz AC line for the clock/calendar, then I wouldn't think that the processor internal clock calibration would matter.
Title: Re: clock running fast
Post by: Dan Lawrence on September 18, 2009, 11:49:48 AM
The problem in this thread is that the OP (jfaska posted only twice and never posted any more. We don't know what he did to solve his CM15A clock problem.
Title: Re: clock running fast
Post by: dave w on September 18, 2009, 12:36:36 PM
The problem in this thread is that the OP (jfaska posted only twice and never posted any more. We don't know what he did to solve his CM15A clock problem.
Yes, good point. Would be nice to know if the problem was fixed and how.
Title: Re: clock running fast
Post by: dave w on September 18, 2009, 01:02:27 PM
The CM15As controller chip. CY7C63723 has an input for a crystal but in the schematics it looks like X10 chose to use the chips internal one
Yeah Brian, your are right. When I did my antenna mod, I thought I saw a "watch xtal" on the board. But I just checked and conclude it was hallucination (or wishful thinking). So the clock for the micro P pretty much free runs?
Title: Re: clock running fast
Post by: tjosan on September 19, 2009, 10:30:25 AM
You are incorrect.  What was posted by : MANOWAR©  was the correct thing to do.  There are so many electronic devices that make noise and can alter the electric power frequency slightly.  The biggest noise producers are cell phone chargers and number one is the PC, desktop and laptop.

As someone pointed out, when I switched for a new one the same problem would have existed, right. After changing for a new
CM15 it's been running fine for a year or so.
Title: Re: clock running fast
Post by: jfaska on October 01, 2009, 07:45:38 PM
x10 sent me a new one it was ok for about a week

last night it picked up a few minutes

I'll have to watch and see what happens (and see if anyone remembers pulgging in anything last night)
Title: Re: clock running fast
Post by: GeorgeM on January 01, 2010, 09:23:40 AM
Here is some parallel information.  A couple of years ago, my electric utility upgraded to remote meter reading.  I knew the then chief engineer of the utility and he gave me a thumbnail description of how the system worked.  It modulates the AC zero crossings digitally.  And so, all my old digital clocks started running fast because there were now additional zero crossings.  I started opening them up, and discovered that the RC low pass filter shown on the chip data sheets was absent in every bloody one of them.  Even though I found 3 different clock chips, none were in circuits recommended by the chip designers.  All different makes and models of clocks, including some clock radios.  Adding the recommended resistor and capacitor fixed the problem.  My CM 15 runs fast for this same reason, and I will eventually get in and filter the optical coupler output which provides the 60 Hz signal to the CY7C63723 chip. 

The real problem which arises here is that any filter added externally to the CM15 will also remove the output signal.  I may end up bringing the output out on a separate set of conductors, plug the CM15 into a UPS, and feed the output directly into a power outlet. :o
Title: Re: clock running fast
Post by: JeffVolp on January 01, 2010, 10:28:41 AM
My CM 15 runs fast for this same reason, and I will eventually get in and filter the optical coupler output which provides the 60 Hz signal to the CY7C63723 chip. 

Something to consider is that any simple filter that eliminates noise will also shift the zero crossing, which is used to time transmissions and the X10 sample window.  Too much delay and you may have trouble sending and receiving X10 commands.

Jeff
Title: Re: clock running fast
Post by: Brian H on January 01, 2010, 01:26:49 PM
GeorgeM; I am not that surprised the reccommended parts where missing in the clocks.

Study the CM15A schematics and you will also notice none of the chips have a .1uf bypass cap on them. That are what would be called standard practice for digital designs. We had an electronics engineer report that after adding four .1uf caps to his CM15A it was much more stable. He added one on VCC to VSS for U1 and U2. Also across C11 and C12. Not sure if he also used on on C2.

My early revision CM15As don't have the caps. I don't know if on later ones they maybe soldered on the back of the board.
Title: Re: clock running fast
Post by: dave w on January 01, 2010, 04:33:55 PM
IT'S THE DAMN BEAN COUNTERS AGAIN!!!
Title: Re: clock running fast
Post by: JeffVolp on January 01, 2010, 08:14:48 PM
IT'S THE DAMN BEAN COUNTERS AGAIN!!!

Maybe...  While they cost me about a dime each, they probably only cost one or two cents each at the quantities they would buy.  And you really only need one high frequency bypass on a small low-current PCB like that.  Of course it also costs something to install onto the PCB, but we aren't talking big savings by leaving it out.

Jeff
Title: Re: clock running fast
Post by: dave w on January 02, 2010, 04:40:27 PM
IT'S THE DAMN BEAN COUNTERS AGAIN!!!

Maybe...  While they cost me about a dime each, they probably only cost one or two cents each at the quantities they would buy.  And you really only need one high frequency bypass on a small low-current PCB like that.  Of course it also costs something to install onto the PCB, but we aren't talking big savings by leaving it out.

Jeff
I think it is the X10 mindset. I have seen them take out caps before. "If it will work with out it...leave it out".
Title: Re: clock running fast
Post by: Brian H on January 02, 2010, 04:45:51 PM
dave w; If you have ever looked at some of the X10 schematics on the FCC site?
Components with a * are not installed.
Title: Re: clock running fast
Post by: GeorgeM on January 19, 2010, 11:29:34 PM
Now, here is an interesting development.  After I retuned the output frequency on my CM15A, I plugged it in at a location I had not previously used, but which is more convenient to the computer.  It appears that it is no longer gaining time.  I have no explanation, and presently have too many other hot projects (repairs) to pursue an investigation, but wanted to report the new condition.  Previously, I would have had to reset the CM15A time at least once by now, but it continues to stay synchronized.  I'll check back in if I ever have time to run the tests to determine what has happened.  I think this outlet shares a circuit which may have equipment with serious line filters installed, but until I have the time to chase it out, I can't be sure.