I have a Lutron Caseta Switch (not dimmer). It powers a single led bulb. I don’t know the actual wattage of the bulb, only that it’s a 75 watt equivalent.
When the switch is off, the led bulb is not completely off, but burns dimly.
The model of the Caseta switch is supposed to be the one that requires a neutral. I thought with a neutral connection, it would mean the led would turn completely off.
I thought the model of the switch that doesn’t require a neutral means that a small amount of current flows through the circuit even when the switch is off, meaning that with a small load, the bulb might keep burning dimly.
Am I correct in my understanding? Is it possible that somehow I have the wrong model of switch, the one that doesn’t require a neutral? Or, if I actually have the correct switch, that it was wired incorrectly? I had an electrician install the switch.
It's possible that the switch leaks a bit of current. I only have Caseta dimmers so maybe someone will correct me on this. If there is an audible click when tuning on and off the switch, then there is a relay inside that opens it there isn't it's a solid state relay and it can leak a bit.
If your power comes from the light fixture to the switch and back on what's called a switch leg, when the switch is open (off) these wires can act as a capacitor and due to the low power requirements of an LED bulb can cause them to glow slightly.
Actually, caseta switch model # PD-5WS-DV does not require a neutral (I have a few).
If you look at this spec sheet, you’ll see Lutron does warn that glowing when the switch is off can occur with the non-neutral model at low wattages (eg with LED bulbs). They do recommend installing a device similar to that aeotec bypass in the linked thread.
I’m not sure if that can occur with the neutral-required caseta switch, PD-6ANS. I would think no, but I’m not an electrician.
It does not in my experience. I have one of those controlling two 6 watt LED bulbs. After I read your post, I removed one of them, and the other stays off. I suppose I could actually measure the voltage in the bulb socket when the switch is off, but I'm reluctant to do that right now.
Edit: There is definitely leak-through voltage/current even with the PD-6ANS. I removed one bulb and replaced the other with an older 8W LED filament bulb. When the switch is off, the bulb continues to flash (rapid on/off).
I have about 60 + Lutron switches/dimmers and it does occurs for me in some. Most of my LED bulbs are same (so I think it depends on the wiring and not the bulb or the switch).
It's not strange. They are control by electronics inside unlike the dumb switch or other smart switches with relays.
Not to mention all these standards for LED circuits.
But if there's a physical relay inside (presumably on load), then there should be a complete absence of current on load when the switch is off, no?
I guess, it must have some sort of solid state relay that permits low level leak? I don't know enough about electronics to know if that's even feasible.
I specifically chose the the PD-6ANS switch because I understood that the neutral wire would mean no low level current leakage and therefore no low level lighting when the switch is turned off.
Apparently, my “understanding” was a misunderstanding.
Why does Lutron make two types of switches, one that works without a neutral and one that requires a neutral (PD-6ANS)?
FWIW I had to install a bypass on a newer model Inovelli switch(not dimmer) as well that also has a neutral; older model didn’t require it. This was for a switch that operates a LED transformer where LED lights attached to th pie transformer would flicker every ie and then when off. My neighbor had same exact situation with a Caseta switch that controlled a transformer as well and bypass solved it.
I recall reading that the newer relays used require a minimum load to actually turn completely off so the bypass solves that.
These devices must be using a solid state relay of some sort, as @aaiyar mentioned. I checked a few of mine yesterday and I cannot hear the telltale click of a mechanical relay.
It’s strange to me because my understanding was that the negative wire required by this particular switch would prevent low level current from going to the bulb when the switch is in the off position.