The bulbs will not come on (meaning light atually coming from the bulb) from an OFF state if the level is set to less than 70 when light is turned on. For example:
Dimmer on, Level = 100, Set Level to 5, Light is on and dim. Set to anything between 5-100 from there and it all looks right.
But,
Dimmer off, Level = 5, Turn Dimmer on, light is not visibly on
Set to 10, still not on
Set to 20 through 60, still not on
Set to 70, light comes on at 70
Then if I ramp back down from 70 to anything down to 5, it is showing what I expect is the right amount of light
The events and actual state data of the dimmer in Hubitat all looks correct after each level change.
Sounds like you need to set the "minimum brightness" parameter (number 10) to 70, or maybe some value below that where you can still tolerate oddities. If you don't like the way that looks (too bright?), I'm not sure what else you can try with the dimmer itself, but different bulbs might be the easiest option unless you wanted to see if a ZEN77 or other dimmer worked better.
Inovelli has a dimmer with a "'smart' ramp up then down" option to coax some bulbs to lower levels, which it sounds like works for you, but I'm not aware of anything here. You could, I suppose, create an automation on the hub to do something similar, but it will probably be a bit slower.
LEDs are, in general, a lot pickier than incandescents when dimming, so luck tends to vary with different manufacturers of both.
Yea 70% is too high for a minimum. I want to be able to use all the way down to 5-10% which does work but not from off. Are you saying this is most likely something to do with the bulb and not being able to turn on from low dimmer levels? Like it needs to be "activated" with high amounts of power before going low?
Probably? There may be dimmer firmware issues too, and Zooz support may have some ideas if no one else here does. But LEDs are pretty picky. It looks like their newer dimmers all use TRIACs, so that or "leading-edge dimmer" compatibility would be good things to look for on your bulbs (unless you have an older unit). Can you find any information if you look up your exact bulb model specs?
It's the latest version of ZEN72 running latest firmware and driver. I linked the Philips spec page in the OP and it just says "Dimmable: Only with specific dimmers". I found this compatibility PDF and it has some Leviton and Lutron dimmers marked as compatible but I'm having problem figuring out if those dimmers are TRIAC and/or leading-edge.
Sorry, I'm not a philips user so I didn't know the difference. However the same suggestion goes, change the bulb type. And if you still have one, try an incandescent bulb.
Again, this is just for troubleshooting.
Another thing you might try if you can't find other bulbs (or like these enough you don't want to try): a "bypass" like the Fibaro, Aeotec, or Lutron MLC might help reduce the minimum level you're able to set while still getting light (what effect this will have on the output, I don't know; it's normally used if you're in a no-neutral setup and don't have a high enough load to power the dimmer itself or run into problems like flickering).
Tried some Luxrite dimmable LEDs and they work a lot better but still exhibit some of the same behavior at low levels. e.g. If I start at 100 and ramp down to 10 that looks one way. But if I then turn the light off and back on to 10, it turns on but isn't as bright as it was before. Need to ramp power back up then down again to match the previous brightness.
The Leviton 6631 is identified as an incandescent rated dimmer. ALL the incandescent dimmers I've ever seen are TRIAC based, which means they are turn on late in the cycle to dim the load. I would call this leading edge control.
In addition, I would reach out to Zooz. Their support service is 2nd to only Hubitat.
