LEDgardener

Usually, for low cost luxmeters (<100$) it depends on the spectral distribution of your lamp. The highest error is for both blue and red dominant spectrums.
If you are not using correction factor you can even get twice the amount you are supposed to measure.
Tho, a low cost luxmeter is not a problem, you can get very accurate measurement using correction factor. But to got this number you need the response curve.

unfortunately i can't find any datasheets for your luxmeter so anyway.

LivingLight wrote: ↑

Thu Apr 19, 2018 9:56 am

unfortunately i can't find any datasheets for your luxmeter

i found the relative sensitivity curve they also list correction factors:
x 1.1 for mercury lamps,
(x 1.0 for: CFL, cold light, daylight)

Anyone made any real life voltage measurements of the vesta strips? Im trying to confirm if i can run 9 vestas (one channel) at 1400mA on a hlg320-c1400. Max Output voltage is 229V so would be a real tight fit, estimating 25.25V at 1400 mA.

Rocket Soul wrote: ↑

Sun Apr 22, 2018 10:29 am

Anyone made any real life voltage measurements of the vesta strips? Im trying to confirm if i can run 9 vestas (one channel) at 1400mA on a hlg320-c1400. Max Output voltage is 229V so would be a real tight fit, estimating 25.25V at 1400 mA.

by "one channel" do you mean "2700K AND 5000K together" or only one of the channels "2700K OR 5000K"?

tazztone wrote: ↑

Sun Apr 22, 2018 9:06 am

LivingLight wrote: ↑

Thu Apr 19, 2018 9:56 am

unfortunately i can't find any datasheets for your luxmeter

i found the relative sensitivity curve
20180422_105535-01.jpeg
they also list correction factors:
x 1.1 for mercury lamps,
(x 1.0 for: CFL, cold light, daylight)

Okay nice, that means your luxmeter is calibrated on a 5000 or 6500k CFL, with these informations i think i can give you a decent correction factor. For now i'm busy but i'm gonna do it within a few days

Hey Tazz. The idea is to use 9 strips with one 320hc1400. The current comes out of the driver and goes to a 3way wago. Out of the wago i have 2 lines, each with a light switch rated for voltage/current of the driver, one going to 2700 the other to 5000. That way i could easily switch between 5000 and 2700 and also use half and half/paralell. But will 9 strips run at 1400 on a hlg320c1400?

why do you wanna run each Row at 1.4A when they are rated 1A?
700mA sounds much more reasonable

I want the option of running either channel at 1400 or both channels in paralell at 700 each.
Its rated at 1 amp nominal per channel, 2 amp max so its within specs, at least in my understanding.
This fixture is really for a friend whos converting to led. The idea is to get him a fixture with variable spectrum, to be able to evaluate how spectrum affects stretch/transition and other photomorphological effects. We are building a few different ones for him to see what he likes more. This fixture would the more spectrum driven, the rest are straight 3000k.

probably okay if you have a decent heat sink. because they get fairly warm.
when i tested both rows at nominal current it reached 41°C (ignore temp. on picture)
(with 10mm heat transfer tape and aluminum curtain rail): anyway
it should work with the driver you mentioned. even if it's 25.4V. and even if it doesn't you could always dim down the output amperage of the driver with a (variable) resistor. right?
unfortunately i cannot test the vestas voltage at 1.4A because my driver only reaches 25V max.

Hey tazz

I finally got the results for your luxmeter.
To get a corrected lux measurement for the vesta full spectrum you got to multiply the luxmeter reading by 0.92
it is an approximation of course because it depends on the calibration
For a calibration on a 6400k Cool White CFL i got: 0.9287
And for a calibration on a 5000k daylight CFL i got 0.9089
So i think 0.92 is a decent approximation. Considering the curves' digitalisation, it's not relevant to be too accurate.
You can use this correction factor to get a better lux measurement and then use the lux to PFD conversion factor or any other conversion factor for your vesta.

If you want it for another spectrum, idk maybe the 2700 or 5000k vesta alone, now i got the data it's gonna be easier.
If you want more informations on the process or the spectrums i've been using, just ask