Insteon Micro Module Sense Circuit Fried

[cmacnichol]

Well.  Right about now I am regretting not investing in a whole home Surge Suppressor.  That was one of the things on the 'To-Do' list.

 

I have a pretty modest system with about 20 modules total.  Five of them happen to be a mixture of Insteon Micro Dimmer's and On\Off modules.  I have had the five micro modules since they first came out and have had nothing but trouble with them, having had to get them replaced twice by Smarthome.  Unfortunately with the way my Bathrooms are wired I have to use micro's if I want to control everything.  Just bought the Z-Wave module to start investigating their relay modules as well.  Though that is another issue as one of my bathroom devices is for a 1500 Watt Heater, which the insteon micro on\off can handle, but most Z-Wave seem to be a 10 Amp limit.  But that is another issue.

 

Now, to my Actual issue.  A few days ago, a day after I bought Z-Wave in fact, we had a small thunderstorm in the area with some power flickering.  I did not notice until the next morning that my Micro switches were randomly turning on\off by themselves with no Insteon traffic to explain it. After some investigation I found that all of the Micro Devices I had installed would no longer reliable work on command from the sense wire.  Remote Control and reporting from\To the ISY are unaffected.  After much frustration and smelling something burning from one of them I got them removed and popped one open.  There is a small burn mark on where the Sense wire connects to the board so their was definitely a surge of some sort.  Confusing to me here, is that NONE of my other devices appear to have been damaged in any way.  So I am assuming it is something to do with the micro module design.

 

So here is my situation as it stands.  

 

I have 5 Assorted micro modules that all still respond to remote commands promptly, but where the sense circuit seems to have been damaged.

None of the 5 are still under warranty as these were warranty replacements themselves (Not that it most likely would of helped)

The sense wire works for a minute or two after power is applied to it, then stops.

 

In the vain hope that I am not out almost $250, would anyone here had something similar happen and been able to repair them?  Even a circuit diagram of the Micro Module would be helpful at this point.  Considering most of the device is still responding and working normally I am hoping it just fried a MOV or few.  Or at least something that is replaceable, but I do not really want to un-soder anything unless I know exactly what it does.  Really wish I still had an Oscilloscope.

 

Thoughts?  Opinions?  Tell me I am in a hopeless situation?  All are welcome, well, the first two more than the last.

[Teken]

I am a true believer that a whole house SPD is very much worth the investment but sadly these devices do not offer protection in several scenarios.

 

Keeping in mind there are five types of SPD's and there are three common ones people are most familiar with: Type 1, Type 2, Type 3.

 

Type 1 is a primary surge protective device normally installed at the meter entrance from the POCO. This offers the most protection as it intersects with the power lines coming into the building.

 

Type 2 are secondary surge protective devices which are normally installed at the main principle panel. Type 3 are also considered secondary surge protection devices which are often called point of use.

 

They can range from surge outlets, surge bars, line conditioners, to UPS.

 

In all cases each of the three have specific voltage clamping specifications and do not operate until a threshold has been seen / met.

 

Meaning if you had a small surge the Type 1 /  2 may very well not have done any voltage clamping. This is why a layered approach is often highly recommended because Type 3 start to clamp / shunt at a much lower voltage / amperage rating.

 

In all cases a standard SPD offers absolutely no protection against what people often call a *Brown Out*. In technical terms its called a voltage sag / lull.

 

Despite common belief a voltage rise (surge) does not happen just when lighting is present. Everyday your home is inundated with micro surges which are caused from with in the home itself. Anything with a motor, compressor, highly resistive loads that have a quick inrush current draw like LED's etc.

 

All of these appliances / devices cause massive micro surges that most electronics are designed and able to sustain. What many electronics are not designed to endure is extended voltage sags or where the voltage rises past the makers stated operating range.

 

Most electronics are able to sustain voltage from 85 - 150 VAC for brief periods of time with out issue. If the voltage remains in this range exceeding minutes depending upon the power supply and how well regulated the circuit is.

 

Things either are fine or go poof . . .

 

Regardless of all the technology listed above - all of these devices rely on single point solid ground wire to Earth which must have low resistance below 50 ohms.

 

Even the best Earth ground using Ufer grounding will not protect the electronics from induced voltages which can be present during massive lighting strikes which translates to huge (EMF) EMI / RFI in the air.

 

Back on topic: As you probably noted the Micro On-Off module is very compact and most of the components are SMD devices. If I was to undertake this task I would summarily replace any capacitors, diodes, as my first step.

 

You will be very hard pressed to replace the SMD resistors, capacitors, and diodes however. I've done board level repairs for more than 25 years and with out the proper equipment, tools, and experience it makes repairs extremely difficult.

 

This also assumes you're able to determine all of the values and purchase them from Digi Key / Mouser.

 

If any of the transistors are smoked you're pretty much SOL in this area then. 

[cmacnichol]

Thank you for your Very detailed response.  I have a pretty good background in electronics and some of that I had not known, so useful information to have.

 

The only reason I am in any way hopeful is due to how they behave without the sense circuit hooked up, in other words, complete normal operation.  This is one of the reasons I wanted to get a circuit diagram, as at that point I could at least use them as in-line relays with a keypadlic as the controller, which I have an extra of I had planned to use for a later project.  I planned ahead when I wired one of the rooms and have a junction box I can use in line with the circuit.  Unfortunately that will only save 3 of them as the others are in places I cannot replace.

 

I just do not know how isolated that portion of the circuit is from the rest to feel safe enough to hook them back up.  From visual inspection, it does not appear to be linked to the parts that contain power, which would make sense if all the circuit did was detect the 120AC from the sense wire when the switch was used.

 

I might just have to perform some surgery on one of them and see what happens.  Doubtful that Insteon\Smarthome would provide a circuit diagram...  was hoping someone here had broken the board down in the past.  I know the people here are the type to do it just to figure it out.    I hate working with boards this small myself, not looking forward to it, but at that cost it is worth some time to at least see if I can repair them.

 

Thank you again for the response though Teken, I do appreciate it.

 

If anyone comes across a circuit diagram on these things or knows something about them, please let me know.

[Brian H]

I doubt you will find schematics of the module.

 

In the FCC Database there are all of the Dual Band devices. Including the Micro Modules

 

https://apps.fcc.gov/oetcf/eas/reports/GenericSearch.cfm

 

Smartlabs allowed the internal and external photos along with the test results to be public access but the schematics were kept confidential.

 

You can take the FCC ID on the module and put the needed information into the web form. Then pick the details choice after the search.

The public data is available for you to see or download. All the pages have the same name. So change it for your download.

 

The Grantee Code is SBP for the Smartlabs devices.

The Product Code is the rest of the FCC ID.

[Teken]

Thank you for your Very detailed response.  I have a pretty good background in electronics and some of that I had not known, so useful information to have.

 

The only reason I am in any way hopeful is due to how they behave without the sense circuit hooked up, in other words, complete normal operation.  This is one of the reasons I wanted to get a circuit diagram, as at that point I could at least use them as in-line relays with a keypadlic as the controller, which I have an extra of I had planned to use for a later project.  I planned ahead when I wired one of the rooms and have a junction box I can use in line with the circuit.  Unfortunately that will only save 3 of them as the others are in places I cannot replace.

 

I just do not know how isolated that portion of the circuit is from the rest to feel safe enough to hook them back up.  From visual inspection, it does not appear to be linked to the parts that contain power, which would make sense if all the circuit did was detect the 120AC from the sense wire when the switch was used.

 

I might just have to perform some surgery on one of them and see what happens.  Doubtful that Insteon\Smarthome would provide a circuit diagram...  was hoping someone here had broken the board down in the past.  I know the people here are the type to do it just to figure it out.    I hate working with boards this small myself, not looking forward to it, but at that cost it is worth some time to at least see if I can repair them.

 

Thank you again for the response though Teken, I do appreciate it.

 

If anyone comes across a circuit diagram on these things or knows something about them, please let me know.

 

No worries and hope very much you're able to determine what components were damaged so you can undertake the repairs. Its a little hard to measure the values with out a reference which is really what you're going to have to do.

 

If you had one good working unit that would be your reference as you probed around looking for variance. Keeping in mind there will be some drift and errors since everything is inline so the expected values may be hard to determine.

 

If you decide to go forward with this make sure you have nice tweezers, magnifying glass, air driven desoldering pencil, and various thickness of desoldering wick.

 

Having a third arm holder is paramount given the small size of the board to keep it in place.

 

There are quite a few zener diodes in Insteon's hardware so it could be as simple one of them blew and no longer conduct properly when called upon.

 

As an aside I am disappointed to hear your Micro On/Off - Dimmers were not able to survive this surge event. I was really hoping the 100-277 VAC operating range would have offered some kind of buffer. But then again both of the units do not offer any mention of a surge rating like there other brothers do.

 

Some of the latest Insteon devices indicate a 1000 volt surge rating but doesn't offer what this value is referenced to. So I have to take that with a grain of salt given many past failures of their products.

 

I would be extremely surprised to find a MOV of any size in their Micro units maybe a small fuse, resistor, at best.

[Brian H]

If you try and do live readings. Use caution as the module has a power line derived power supply.

I don't know about the micro modules. I do know the older things like the 2456S3 and 2456D. Both have the + Logic power connection directly on the Line Input.

 

I looked at both the dimmer and relay style FCC Internal photos.

Looks like each Sense Input wire connects to two surface mounted resistors in series. Marked 3303.

The other end of the resistors looks like it has some diodes and resistors that connect to the 8 pin IC in the same location. Can't read the part number but it maybe an optoisolator to isolate the Sense Inputs from the unisolated AC floating around in the module.

 

I think the Sense Inputs are a fairly high impedance and not a rugged as the 1000 volt rating for the AC surges.

 

The newer model Insteon devices I have looked at. Use a 3.3 volt DC power so you may see what looks like a low logic supply voltage but it is most likely OK.