Tape lights stay on at low levels even when Maestro CL goes off

Setup:
Armacost 60W dimmable transformer (Lutron Maestro CL listed on its compatibility page)
36" of 120 LED/m white tape lights
Maestro CL MACL-153M

I have two such setups (well, the other has about 60" of tape lights in a Y configuration, but otherwise identical). The setup with the Y configuration of lights works exactly as expected. The setup described above lights up as expected, but never seems to fully shut off.

I have reprogrammed the Maestro to set the low light level as low as I can.

When I switch the light off, the lights still remain visibly on at a low, but quite visible level.

My suspicions lean towards:

a) Insufficient ground (my electrical contractors had previously tried and failed to get these switches working in a 3-way configuration with DALS 6" pots.... so the tape lights is me trying to repurpose them) - the contractors ripped the ground off the switch that is not functioning right (the green wire). I had some 14/2 handy so I cut and stripped a conductor of 14 AWG to use as a replacement ground. It's solid wire and I tried to crimp it onto the tab the green ground wire had formerly been attached to. I'm not 100% sure that connection is as good as the original green stranded wire was.

b) A damaged dimmer - it seems feasible to me the electricians, being in a hurry and not taking the time to fully understand the wiring requirements, may have done something that damaged the switch

Thoughts? Suggestions?

I do have one unopened (and thus never damaged) Maestro CL 153-M, but if I the issue is more likely to be wiring (particularly the ground - I think all other interconnects were done well), then I'd like to investigate those avenues before I assume the switch is cooked and open the other one.

Any advice appreciated.

Tom

Good afternoon Tom B,

While Lutron has not conducted any testing on the LED set-up that you have installed and would not be able to guarantee the performance you will experience, there is a test you can conduct to determine if the control is still good. Since you have one application that is working properly swap the locations of the two dimming controls to see if the issue follows the dimmer or if it stays at the same location. If it follows the dimmer our tech support would be able to replace the MACL, however if the issue stays at the location it would be load related.

Does the working application have more, less or the same amount of wattage as the application that will not turn off? Some very sensitive LEDs can pick up on the very slight trickle charge that the MACL produces while in electronic off which can keep the LEDs from fully shutting down. Also, all of our controls are UL rated to work without a ground connection so even if you still had the original ground on the dimmer hooked up it more than likely would not resolve the behavior you are experiencing.

Please let me know if you have any questions.

Lee Valley, a local vendor, seems to sell your Skylark and Skylark Contour switches with the Armacost transformer and the LED tape lights. I was wondering how the switches behaviour (particularly current emitted while 'off') would differ between those and Maestro CL?

The load that is working completely as expected has 60" of 120 LED/m tape. The load that is still showing illumination has 36" of 120 LED/m tape. Not sure of the wattages (need to look up the equations) but the load for the LEDs should be about 60% of the load that works.

Mind you, isn't the transformer the load? The transformer data sheets suggest its behaviour should be consistent with any load from 0 to the maximum supported. (Of course, that may be the claim and the reality may somehow differ)

Anyway, I have another Maestro CL that is in the package so I can swap it and the switch whose installation is not behaving fully correctly. If the other dimmer that hasn't been opened before behaves the same way, I'd say it isnot switch related.

I can probably also temporarily chain on more of the LEDs to see if changing the load will change the behaviour.

Assuming I don't want more LED tape installed, is there some way I can vary the load (to increase it) without adding new tape? Is there a way to add a resistive load to the circuit that would eliminate the issue?

Observation:
If I use the button for incrementing light level to turn on the Meastro from its off position (where the LEDs are still emitting light), something odd I have observed - the first few klicks reduce the light level below the 'off' level I am observing (it dims 3 or 4 notches with pressing the up button) and then it will start brightening from there to the maximum.

I'm not sure if that observation casts any doubt of the integrity of the switch but it seems odd that current must be dropped a few notches further as I try to bring the light up (versus the 'off' current).

I'll post further data once I try increasing the load temporarily and/or swapping the switch out. I've got countertop issues that have delayed this (ah, renovations.....).

Tom B,

The Skylark control when in the off position completely disconnect the power running out to the lighting load. This dimming control would be able to turn the LEDs off without a question, however we would be unable to guarantee the performance that you will experience with this dimmer since we have not conducted testing on this LED set-up. Also, the only resistive load Lutron would be able to recommend would be to incorporate an incandescent or halogen bulb onto this switched leg.

Please let me know if you have any questions.