Strange behavior between togglelinc dimmer and relay

[oronomus]

Remodeled a bathroom and put a togglelinc dimmer and relay together side-by-side in a gang box.  The relay controls an exhaust fan and the dimmer controls recessed lighting.  The dimmer and relay share a common power source (load) and, of course, share a bundled neutral (white) wire.  Frequently (not always) when I manually turn on or off the FAN, the FAN responds but the lights on the dimmer dim down (to off) and then back on - but, not only just the lights controlled by the sister controller in the same gang box but also lights in an adjacent room that are also controlled by their own togglelinc dimmer (but share a circuit breaker) .  Thinking maybe the FAN controller (relay) ended up with an unintentional  link to the dimmers, I restored ALL the devices several times.  (I never manually linked any devices, only link through ISY).  I even replaced the dimmers, all with no success.  Don't have a spare so I can't replace the relay.  

 

In the event log (attached), I see the fan controller (2B.80.80) but then also see one (but not both) of the dimmers responding to something (25.8A.65).   

 

There were numerous new recessed lights added in this remodel, so the problem might not be in the Insteon devices at all - could be a Romex in the wall that took a nail or bad wiring overhead by the electrician.  

 

Looking for creative ways to keep troubleshooting.  Many thanks...

 

 

ISY-Events-Log.v4.2.4__Thu 2014.07.17 07.28.04 PM.txt

[Techman]

You might be getting a voltage drop when the fan starts up due to a poor electrical connection. . How many watts are your lights drawing?  What type of bulbs are you using, CFL or incandescent?

 

When the lights are on and you turn the fan on does the fan speed seem to initially lag?

[LeeG]

The trace shows 25.8A.65 turns Off by its paddle press, then On by its paddle press.  If these were not done by physical interaction with the device there is a power issue to that device.    

[oronomus]

You might be getting a voltage drop when the fan starts up due to a poor electrical connection. .

 

Good point. My next troubleshooting will be to look carefully at all the electrical connections to both the recessed lights and the exhaust fan.  

 

How many watts are your lights drawing? 

 

Ten recessed cans off one switch in the gang box with the fan relay - 65 watts each.  Five recessed lights off a switch in another gang box - 65 watts each

 

What type of bulbs are you using, CFL or incandescent?

 

Gang box 1 - nine incandescents and one or two Cree LED spot 65 watts.  Gang box two - five incandescent 65 watts.  I'll pull the Cree and one incandescent at a time.  See if it makes a difference. 

 

When the lights are on and you turn the fan on does the fan speed seem to initially lag?

 

Doesn't seem to lag, but it's a ceiling exhaust with a very quiet motor.   I'll get on a step ladder and have my wife turn it on and off, see what I detect.  The lights typically react when the fan is turned off, not when it is turned on.  Not being an electrical engineer, that puzzled me in concept.  Seems like most troubles would appear when the fan is turned on, not when it is turned off.  

 

The trace shows 25.8A.65 turns Off by its paddle press, then On by its paddle press.  If these were not done by physical interaction with the device there is a power issue to that device. 

 

The 25.8A.65 responses were NOT physical.  So I will continue to troubleshoot toward an elelctrical connection issue.  I have carefully tested the conections to the Insteon switches, so next step is to test the connections to the lights and fan.  Also, make sure no wires are crossed where I have visual access.     

[paulbates]

Your note says just one line / breaker. I had a case where I thought that but it was actually 2 lines for 2 breakers had been tied together, one old and one new from new construction.

 

The behavior I got was a little different, it caused a keypad linc to get noisy and then quit working and need to be reset.

 

If the other suggestions don't solve it, you may want to try unbundling the switches and measuring all lines in that box with a voltmeter to see if more than one is hot.

[Techman]

 

How many watts are your lights drawing? 

 

Ten recessed cans off one switch in the gang box with the fan relay - 65 watts each.  Five recessed lights off a switch in another gang box - 65 watts each

 

 

What type of bulbs are you using, CFL or incandescent?

 

Gang box 1 - nine incandescents and one or two Cree LED spot 65 watts.  Gang box two - five incandescent 65 watts.  I'll pull the Cree and one incandescent at a time.  See if it makes a difference. 

 

I would  first try removing the LED bulbs to see if that makes a difference as it may not be a good idea to mix bulb types. Make sure your load doesn't exceed 600 watts per switch, it looks like you're just about at the limit.

.

If you have two dimmers side by side in a two gang box then you must reduce the maximum allowable wattage to 400 watts per switch due to heat dissipation

 

 

When the lights are on and you turn the fan on does the fan speed seem to initially lag?

 

Doesn't seem to lag, but it's a ceiling exhaust with a very quiet motor.   I'll get on a step ladder and have my wife turn it on and off, see what I detect.  The lights typically react when the fan is turned off, not when it is turned on.  Not being an electrical engineer, that puzzled me in concept.  Seems like most troubles would appear when the fan is turned on, not when it is turned off.  

 

The trace shows 25.8A.65 turns Off by its paddle press, then On by its paddle press.  If these were not done by physical interaction with the device there is a power issue to that device. 

 

The 25.8A.65 responses were NOT physical.  So I will continue to troubleshoot toward an elelctrical connection issue.  I have carefully tested the conections to the Insteon switches, so next step is to test the connections to the lights and fan.  Also, make sure no wires are crossed where I have visual access.