Just metered my beds for the first time. Got some questions.

[SouthBeachSunWV]

I metered one of my beds (100W) with new bulbs and new acrylics and it read 33.5 on the 5.0, and .96 on the 6.0.

These normal readings on brand new bulbs?

Should I wait another 20 hours of bulb life to get a more accurate reading?

[solarmeter®]

The 33.5 is quite OK for 100W. Are they new era or old era?

The 0.96 / 33.5 = 2.87% UVB... so probably new era.

They might go up a bit as they break in (10-20hrs) - and swirling stops. Then, of course, they will head down maybe 15% in 100 hours and slowly fall 30% in about 500 hours+.

PS: Old era peaks at 350nm and usually has higher percent B and lower amount of A.
PS: New era peaks at 365nm and usually has higher amount of A and lower percent B.

If you don't know which kind you have, ask your sales person... or if he/she says "huh?" then ask John at URI.

[SouthBeachSunWV]

Originally Posted by solarmeter®

They might go up a bit as they break in (10-20hrs) - and swirling stops. Then, of course, they will head down maybe 15% in 100 hours and slowly fall 30% in about 500 hours+.

Wow, spot on. I tested a bed with bulbs that had 522 hours on them and it read 22 on the 5.0. A little over 30% drop from the new bulb reading.

[SouthBeachSunWV]

Also, what exactly do you mean by old era/new era?

What are the pros/cons of each?

Thanks for the education!

[Shane]

New era would be something along the lines of 9K90's. Old era would be more like a Beach Sun lamp.

hope that helps.

Also, don't use your 5.0 to compare 1 bed to another. Only use it to calculate % drop in that bed.

Each bed could have the same exact lamps, brand new, and meter slightly different.

[SouthBeachSunWV]

So how do I know if my beds are running well if I don't compare a new bulb bed to an older bulb bed? (Assuming they are the same make/model)

[Shane]

If they are the same make/model, the reading should be close, but are normally slightly off.

It's really made to meter when new and measure drop off from there. BUT it will give you a close idea for now until you relamp the ones with older lamps.

[solarmeter®]

If the lamps and the beds are the same make/model then comparing them should be fine. Any differences in voltage, cleanliness and acrylic age could influence the readings.... but usually not too much.

But like Shane says... different beds with more or less lamps and higher or lower canopy will read significantly different even with same kind of lamps at body position.

[Drew]

.96 is a 6.5 lamp in a 24 lamp bed with the top closed and meter placed on bottom acrylic pointing up.

.85 is a 5.0 lamp on the same bed.

old era lamp

[solarmeter®]

Hey - I thought you threw your 6.0 meter in file 13.

.96 is a 6.5 lamp in a 24 lamp bed

Not if the 5.0 meter (in same position) is reading 33.5. Then it's a 2.9 lamp. Sounds more like new era to me.

IF the 5.0 was reading down at 14.8 then it would be an old era 6.5 lamp. 0.96/14.76 = .065 = 6.5% B.

Perhaps you should send me your meters back for a re-cal check. They are getting older than dirt. Older than Don Smith now! I know they last virtually forever... but yours have been used and abused for a hundred duty-cycle years.

One duty-cycle year = 50 on-button pushes. The blue-tooth chip in your 5.0 tells me it now has >5000 pushes. It reads out on my car On-Star display and on my top secret ssl gps spy website.

[Drew]

I don't use the 6..i just remember the numbers.

I know what beds and lamps are supposed to read so I can re calibrate them myself. but I don't drop them so they stay good.

I would send them back if I thought they were F'ed up..trust me.