Circuitry Inside a LampLinc?

[Wingsy]

InsteonPushbutton.png
Question for those with knowledge of circuitry inside a dimmer:

The above scope trace shows the voltage across the UP button on a LampLinc. I cannot fathom what kind of circuitry this pushbutton is driving. Makes no sense. 15v @ 60Hz one polarity and 5v steady in the other. Any ideas?

(What I'm planning to do is to install a photocoupler inside the box and run a pair of wires out to my controller so that I can control the UP button. My goal is to eliminate the curse of the "ALL-ON" event. It's that or the wife says, "take em out".)

[BLH]

Since you mentioned the Up and Down buttons. You are talking about the 2457D2 Dual Band and not the older 2456D3 power line only module

Be very careful.
The FCC Database shows it has a LNK354 switching supply in it but no isolation transformer.

If I measured from the correct controller chip programming socket pin.The Logic +5 volt DC is connected directly to the AC Line Input. I know older models do have the +5 volts connected to the AC Line Input and all the voltage regulation is in the DC Logic common back to Neutral.

Some of your waveform could be from the common is referenced back to Neutral through the voltage regulator for the common DC reference.

I would see if I could see any voltages between +5 Volt Logic supply and earth ground. That could indicate you have Line Voltage on the external wiers you are trying to add.

[Wingsy]

Thank you for your reply. Yes, I'm aware of the fact that the circuit has no transformer and is connected directly to the line. That is why I will be using an optically isolated switch in parallel to the pushbutton. My wiring to the photocoupler will be isolated from the circuitry - I just need to be sure I allow enough room where my wires exit the enclosure so as to not be close enough to any conductor inside the box for there to be any arcing.

Everywhere I have an IOLinc and/or an Open/Close sensor I get an ALL-ON event about every 2 weeks or so. I have them in a lighted stairway, garage door, and driveway sensor. I have about 90 2477D dimmers and a few 6-button and 8-button dimmers in my house and not once has any one of them caused an ALL-ON event when turned on or off. So, I'm going to modify a LampLinc so that my contact closure inputs activate the ON button in a LampLinc. I checked out the ON switch in the LampLinc with a scope so I would know what voltage rating I need for the photocoupler. I have some 60v AC photocouplers that I will use.

But I'm still baffled by what kind of circuitry would account for the weird voltage I see across the ON button.

[BLH]

It maybe possible. If you scope was on DC Common. It was actually seeing some of the voltage regulation back to Neutral.
I suspect the side with the AC wave form maybe what the are using for Logic DC Common and ground.
Did you measure between the two switch contacts and see if it was 5 volts?
Input may even be pulled up with a resistor to logic 5 volts or the controller has a weak built in pull up.

[Wingsy]

The scope WAS between the switch contacts. That’s what’s so puzzling.