In my main electric panel I have a breaker for a sub-panel. That sub-panel is connected by approx 40-80 feet of wiring in an underground conduit.
On the sub-panel there is a 2477SA1 for a sprinkler pump, as well as a 2475SDB dual band inline linc for pool lights. Each with a dedicated breaker. In addition there is another breaker connected to a GFI outlet and the only thing plugged into that is a low voltage transformer for garden lights.
The issue is when the breaker for the GFI is on and the garden lights are on the 2475SDB can not be controlled and the ISY reports that it is not responding. Can't comment on the 2477SA1 because that device has always been flaky (and now discontinued, surprise!)
What would be the best way to resolve this to ensure that communications with the 2475SDB is always reliable?
Another thing to note is right above the subpanel I have a dual band micro dimmer for a spotlight wired to the main panel. You would think that this would the inlinelinc to function via wireless despite any interference on the electrical lines. I can communicate with the micro dimmer with hops left = 3 per the ISY logs.
RF distance can be effected by anything between the two modules or if they are in metal electrical boxes. It is possible the RF just can't communicate between the two modules.
Is the low voltage supply a transformer or is it one of the more modern supplies with electronics in it?
Check you Dual Band modules manuals. For the builtin communications test. That shows if the modules are communicating by RF and if on the same or opposite phase of the home. Maybe called the 4 Tap Test or Beacon Test. Some models need you to follow a flow chart of Set Button pushes and LED flash patterns. Others just tap the Set Button 4 times and then observe the LED flashing pattern on other Dual Band modules.
If everything works when the garden lights are off (or unplugged), but not (or sporadically) when the garden lights are on, I would tend to consider the garden lights as the primary suspect. Try putting it on a filter.
Is the low voltage source a transformer or one of the most advanced power supplies with electronics? Read the manuals for the Dual Band modules. For a built-in communication test. This shows if the modules are exchanging RF and if they are in the same or opposite house phase. It may be called a 4-touch test or a beacon test. Some models require you to follow a block diagram of Set button presses and LED blink patterns. Others press the Set button four times and then watch the LED blink on the other dual-band modules.