3-way Caseta switch plus mechanical switch configuration not working with LEDs

[lahontan]

I set up a Caseta Claro switch with a mechanical 3-way switch as shown on this page: https://assets.lutron.com/a/document...93_page_81.pdf The key point with this configuration is that the control line (blue wire) may be connected by the mechanical switch to the load side of the Caseta switch.

This configuration works fine using a 60W incandescent bulb. It does not work correctly using any of the LED bulbs I have on hand (Cree, Philips, Sylvania, each in multiple wattages).

An LED bulb turns on normally using either the Caseta switch or the mechanical switch.

The LED bulb turns off correctly in two of the four possible cases:

1. Using the Caseta switch when the blue wire is not connected to the load wire.
2. Disconnecting the blue wire from the load wire using the mechanical switch

The LED bulb does not turn off correctly in the other two cases:

3. Using the Caseta switch when the blue wire is connected to the load wire.
4. Connecting the blue wire to the load wire using the mechanical switch.

In cases 3 and 4, the LED bulb and the status led on the Caseta switch flash continuously about twice a second. The flashing appears to continue indefinitely. As I said above, all four cases work correctly with an incandescent bulb - it's just LED bulbs that cause this problem.

Is there a fault in my Caseta switch? If the switch is behaving as expected, is there any solution/workaround to make this specific wiring configuration work? (I am aware that other wiring configurations work, so please don't suggest that.)

[Travis H.]

Hello lahontan,

We appreciate your inquiry and are happy to assist. The blue wire on the Caseta device is only utilized for communication, hence why it is used to the solo wire on the brass terminal on the mechanical switch and not the load control modification with the yellow jumper wire. Please verify that regardless of its position (line/hot side or load side), that the Claro Smart Switch has power incoming on its black wire, load on its red, and communication (preferably the non-black traveler wire in your wallbox) is on its blue wire. Then modify your mechanical switch by ignoring the traveler you attached to blue and combine the remainder. Please also make sure you are attached to neutral on the Caseta Claro.

If the device does continue to flash, please move the Caseta Claro to the load side of the 3-way. This is preferred due to the blue wire and neutral connection having some troubles when a mechanical switch is between them.

We hope this helps!