It is okay of i let on 24/24 a 150w led ?

This is a complicated question that most people here will give you a very simple answer on.... the truth is, its not that simple. You'll see me write PPFD as umol/s it is actually umol/s/m2 but I'm not gonna type that every time. Cannabis growers in general give their plants far too much light, me included. Light is measured by the number of photons of Photosynthetically Active Radiation per second. This is umols/s and you'll see most lights market this number. Plants cannot make use of all this light, without an increase in the other inputs. Imagine the leaf is a factory, it can only go as fast as it slowest operation or what it has the least materials of. So, lets say we are giving it 1300umol/s of light. It would now need, more water, food, and namely, CO2 to make use of all this extra light. The only way a plant is going to make use of the 1300umol/s of light most of the lights market, is to supplement heavy with 1200-1400ppms of CO2. That is only for photosynthesis, then you need to think about how much light the plant is getting throughout the day. That is its "Daily Light Integral". A DLI of 60 is the "perfect" outdoor exposure for a 12 hour day with clear skies brilliant sun perfect conditions ( 2000umol/s). Most likely, you are gonna be around 43DLI, cause nothing is ever perfect. So... back to your question, let's make some assumptions. Let's say you are using a 150w Mars Hydro TS1000 ( cause I know the numbers off the top of my head) You won't get 1300umol/s with this light unless its literally 4 inches away from the plant, and I don't think you are supplementing with 1200ppm of CO2, so lets go to baseline co2. Baseline co2 in most cities is 400ish ppms. At 400ppms we can take in 500umol/s of light comfortably. 18 inches with the mars hydro will give you about 500umol/s Now, lets see what our DLI is at 500umol/s for 24 hours of light. μmol m-2s-1 x (,3600 x photoperiod) / 1,000,000 = DLI 500umol/s x (3600 x 24 ) / 1,000,000 = 43.20 So after all of this, you can run with that light, at that intensity, at that distance, for those amount of hours, and not stress your plants out. Thanks to Nobody'sbuds for all the references and info when I was going through all this. For more information, Dr. Bugbee's Cannabis lighting myths is a great video to watch. Hope this helps!

Generally speaking, you'll be okay. - There's a few risks tho. The important one is, that the plant uses night time to heal up, so any damage, whether if it's a broken branch, cut leaf or nutrient deficiency, it'll take longer for it to heal up if it's on a 24/7 schedule.

You can 24/0 a plant with a LED or any other light without a problem. But you are going to have better results with 18/6 in veg.