Dr. SJ's Spectral Analysis...

TheVillageIdiot · 02/16/2006, 09:31 AM

I have a couple of questions about it...

1. What does CCT stand for?

2. How can I use the info on his site to estimate the increase in my houses electric bill?

3. I understand what PPFD/PAR stand for, but where is this measurement taking place? Is it at the water's surface or at depth?

anyway, i've read a couple of the articles but i couldn't find this info, so if someone has it our can point me to it, I'd be much obliged!

thanks,

Matt (TVI)

TheVillageIdiot · 02/16/2006, 09:39 AM

just to clarify, i'm wondering about that Wattage rating of bulbs, for example, if I get 2x 250w bulbs, is that 250w per hour, second... etc?

mpomfret · 02/16/2006, 12:30 PM

I haven't seen the thread in your first post. Do you have a link for it ?

Your 2nd post. Wattage is a measure for rate of energy usage. 1 Watt = 1 joule/second. The number on your electricity bill is given as kilowatt-hours which is a unit of energy and is more convenient to use than joules (1 kW-h is 3.6 million joules).

To figure out what the effect of your tank will be on your electricity bill you add up the number of kilowatt-hours the equipment will use and multiply that by the energy cost shown somewhere on your bill ($0.15/kW-h maybe). For example if you have a 20 watt pump that runs 24/7/365 you get

20watts * 720 hours in a month = 14,400 watt-hours = 14.4kW-h
14.4kW-h * 0.15 $/kW-h = $2.16 to run the pump for a month.

For lighting you can't simply add up the bulb wattage since the ballast uses some power as well. Its power requirments are probably on the label somewhere.

Matt

TheVillageIdiot · 02/16/2006, 02:08 PM

Matt,

Thanks for the reply!

the website is...

http://www.reeflightinginfo.arvixe.com/

thanks,

Matt

mpomfret · 02/16/2006, 11:32 PM

CCT is correlated color temperature. It's explained in article #1 in the articles menu. It's expressed in degrees kelvin and is supposed to give a measure of the quality of light. Daylight is usually given as somewhere in the 6000K range. A 10000K light will have more blue in it.

The same article talks about PPFD and PAR and says that PPFD is "a measure of the number of photons between 400 and 700nm incident per unit time on a unit surface." It sounds to me like the test is done in air at a standard distance from the source in question. Photons per square meter is going to drop with the square of the distance.

BTW, for power calculations, watts can also be figured by multiplying voltage by current. If you have a resistive load, then the voltage across it times the current through it will give you power dissipated: V=IR. This doesn't work for reacitve loads like pump motors and balasts because the voltage and current are out of phase.

Matt

02/16/2006, 09:39 AM	#2
TheVillageIdiot Registered Member Join Date: May 2005 Location: Woodstock, GA Posts: 894	just to clarify, i'm wondering about that Wattage rating of bulbs, for example, if I get 2x 250w bulbs, is that 250w per hour, second... etc? __________________ Click my little red house! Current Tank Info: 65g Anemone Tank

02/16/2006, 02:08 PM	#4
TheVillageIdiot Registered Member Join Date: May 2005 Location: Woodstock, GA Posts: 894	Matt, Thanks for the reply! the website is... http://www.reeflightinginfo.arvixe.com/ thanks, Matt __________________ Click my little red house! Current Tank Info: 65g Anemone Tank

02/16/2006, 09:31 AM	#1
TheVillageIdiot Registered Member Join Date: May 2005 Location: Woodstock, GA Posts: 894	Dr. SJ's Spectral Analysis... I have a couple of questions about it... 1. What does CCT stand for? 2. How can I use the info on his site to estimate the increase in my houses electric bill? 3. I understand what PPFD/PAR stand for, but where is this measurement taking place? Is it at the water's surface or at depth? anyway, i've read a couple of the articles but i couldn't find this info, so if someone has it our can point me to it, I'd be much obliged! thanks, Matt (TVI) __________________ Click my little red house! Current Tank Info: 65g Anemone Tank

02/16/2006, 12:30 PM	#3
mpomfret Registered Member Join Date: Aug 2005 Location: Houston, TX Posts: 94	I haven't seen the thread in your first post. Do you have a link for it ? Your 2nd post. Wattage is a measure for rate of energy usage. 1 Watt = 1 joule/second. The number on your electricity bill is given as kilowatt-hours which is a unit of energy and is more convenient to use than joules (1 kW-h is 3.6 million joules). To figure out what the effect of your tank will be on your electricity bill you add up the number of kilowatt-hours the equipment will use and multiply that by the energy cost shown somewhere on your bill ($0.15/kW-h maybe). For example if you have a 20 watt pump that runs 24/7/365 you get 20watts * 720 hours in a month = 14,400 watt-hours = 14.4kW-h 14.4kW-h * 0.15 $/kW-h = $2.16 to run the pump for a month. For lighting you can't simply add up the bulb wattage since the ballast uses some power as well. Its power requirments are probably on the label somewhere. Matt

02/16/2006, 11:32 PM	#5
mpomfret Registered Member Join Date: Aug 2005 Location: Houston, TX Posts: 94	CCT is correlated color temperature. It's explained in article #1 in the articles menu. It's expressed in degrees kelvin and is supposed to give a measure of the quality of light. Daylight is usually given as somewhere in the 6000K range. A 10000K light will have more blue in it. The same article talks about PPFD and PAR and says that PPFD is "a measure of the number of photons between 400 and 700nm incident per unit time on a unit surface." It sounds to me like the test is done in air at a standard distance from the source in question. Photons per square meter is going to drop with the square of the distance. BTW, for power calculations, watts can also be figured by multiplying voltage by current. If you have a resistive load, then the voltage across it times the current through it will give you power dissipated: V=IR. This doesn't work for reacitve loads like pump motors and balasts because the voltage and current are out of phase. Matt