electronic timer memory trouble

I'm still downloading the manual but, for starters, I'd say that you probably have transients coming from somewhere. The unit has a 6,000 volt surge suppressor built-in but that's probably only for the in-coming power supply. The transients could be coming from somewhere else.

Also, is your system Properly grounded? Proper grounding can solve a lot of strange problems.

Okay the manual's finished downloading. It says that the data is stored in non-volatile memory and is retained even in the event of power loss or the battery being drained. That would reinforce my thinking that it's a transient thing unless their product has a manufacturing defect.

regards,

Vulcan

Thanks Vulcan

I will check the grounding system and look into transient protection on the load side.

One other issue, the timer is located in a Testco panel five feet from the local utilities pad mounted transformer. That transformer also feeds three small office buildings.

Any chance that five feet is too close?

Thanks again

Our transformers are located in an enclosure far away from any other equipment. Even if the timer's panel is grounded and the transformer's enclosure is shielded, I would still move the timer away from it.

I don't know what kind of non-volatile memory the timer has but it must be something like flash memory since they say that memory is retained even if the battery goes bad. However, that doesn't necessarily mean that it's safe.

I once had a stereo where I had to reprogram the FM receiver everytime I switched it on. The technician I spoke to said that the memory actually works off a capacitor, not a battery, and if power is off for a length of time, the memory will be lost. He advised me to keep the thing plugged in if I wanted to keep the stations programmed. I don't know if that's what you have.

regards,

Vulcan

"non-volatile" is a relative term, since magnets in proximity can cause scrambling of most memory modules.

Two ideas come to mind about that. 1 - Is the box secured with a lock to prevent mischief with a hand-held magnet, and 2 - is it feasible to relocate the timer temporarily or place a grounded metal cover over it to rule out the transformers magnetic properties?

The transformer's metal casing should be grounded reducing the magnetic field outside it to negligible values. If you hold a magnet in your hand, close to but not touching the transformer body etc, you may feel the vibration of the magnetic field. As you move away from the transformer this should diminish rapidly.

Since you must reset the date/time, that would indicate that there is a power source such as a motherboard battery or super-cap holding the 'non-volatile memory' and there could be a hairline fracture of the PCB or a corroded contact.

Or tampering. Put in a secret camera to record activity for a period.

For what it's worth, CJM

Although a ferrous metal enclosure (iron or steel) will reduce the magnetic field from those transformers, sometimes it's not enough. Here is a company that specializes in magnetic shielding materials.

http://www.lessemf.com/mag-shld.html

Grounding the enclosure will reduce the electric field, not the magnetic field, but it's still a good idea. Increasing the separation between the timer and the transformers will decrease the strength of the field, and make the job of any additional shielding materials much easier. Good luck.

I somehow like your post as being probably the reason (or close) to the memory loss....

I would get a mains voltage monitor and monitor the mains as close to the timer as I could get and see what happens.

The monitors can usually be rented quite reasonably for long periods, although the modern units have got much much cheaper, so buying MIGHT be a better option today, especially if you might have a need for such a unit elsewhere.....

The modern units that I have used (4 or 5 years ago!) can "download" to a PC when reading out.....

I gave you a GA because, yes, this has happened to me before except that it happened with a weight controller.

The controller was used for sack filling and we were perplexed when the unit would suddenly stop working. The owner said that they had replaced the unit a couple of times and even when they had switched brands.

It turned out that the relays and solenoid coils were putting out voltage spikes that took out the controller's circuitry. Since the coils were DC units, we put diodes on them instead of capacitors.

Worked fine after that.

regards,

Vulcan

We already put surge protection on the power coming into the control panel. It did not seem to help. I thnk it is a good idea to protect the timer input power additionally. It is pretty important to us to have the astro feature versus using a photo cell. We can shave and hour or so off the run time of the street and parking lights.I will also check for proper grounding and bonding. At one point Intermatic sent me a capacitor to put across the timer input, but the Rep did not put it back on when he replaced the timer the first tme.

Thanks for all the help. I am taking alot of heat to get this right. Intematic and Testco are bailing out on me. They want to blame the local utility even though it is still under warranty.

Thanks

If all else fails ,Tork makes a mechanical timer with an astro feature.

You also need something to stop spikes ON THE OUTPUTS TO RELAY COILS or similar (most important!!). (if you could post some sort of schematic of the external connections to the timer that would help. Give distances and cable types - shielded or not shielded as well!)

I have forgotten if DC or AC at that point (sorry, too lazy to look back in the blog to see if you mentioned it or not!), so you either need a reversed diode across the DC coil, or probably a cap on an AC coil......if cable runs are long, you may need it at both ends.....over 30 feet is long for me personally, especially if they run parallel to mains cables, (a bit of a "no no" that!).

Induced voltages can be easily measured with a digital voltmeter (on AC), but spikes will not be seen (Storage Oscilloscope is good!) and will be the real problem.....Coax may become a requirement if pickup is bad......don't forget, it could induce "itself"!...

That's the crappy beauty of intermatic. I have use their timers for more than a few years. I too have had the exact same thing happen with probably half a dozen of their units. I have finally concluded that they ( seemingly ) manufacture inferioir products just to raise their revenue. I think you should reconsider using their products any further, as yours is Definately not an isolated problem.

Given the environment, I was wondering if you might have moisture condensation in the timer. Is the timer out in the weather? or is it in a heated building?

Considering that other people report having similar problems, I think it is time to hunt for a new manufacturer.

It can get pretty cold and damp where you are at.

Sincerely

Bill

So far, no one has mentioned salt. In your location, the wind carries a lot of salt spray. If the housing isn't well sealed, salt could be accumulating on the circuit board, effectively shorting out the chips. On the other hand, if you are able to reset the board without cleaning it, and it works for weeks or longer, then this is probably NOT the problem.

You want tocontrol street lights, right ? They go on at a certain time, and of at another certain time, right ? And you program those times in a timer module. OK ...
But wouldn't it be much more easier to connect those streetlights to a light sensor ?
You will never have to program again. The lights will go on when it's getting dark, and will go off when it gets light ... The only maintenance you would have to do, is to clean the sensor now and then. No more problems, no more programming, and the lights come on and go out EVERY day at the exact right time ...

Just a thought ...

Someone mentioned that transients my be the problem. The company I work for makes block varistors which may help. I would be glad to send you some if you let me know the operating voltage and your shipping address.

Someone mentioned that transients my be the problem. The company I work for makes block varistors which may help. I would be glad to send you some if you let me know the operating voltage and your shipping address.

I really appreciate your offer. We have two, 220 volt single phase circuits.

National Park Service

201 Fort Mason

San Francisco Ca. 94123

Attn: Paul