PC bulb question

[dgasmd]

I am planing on buying some retrofit 96 watt PC units for my 125 gal tank. The ones I am looking at are the ones sold by hellolights.com They say they are the Japanese 4 pin bulb and sockets.
*What is the light quality diference between the 4 pin ( :: ) and the 2 pin bulbs ( : )?
*Any quality difference between them?

**Also, I was told by someone that VHO bulbs should be changed every 6 months because the light quality degrades enough by then. They also said that PC bulbs should be changed every 6 months as well. Is this true? I had heard from so many other places 9-12 months for PC, but this guy is very adammant about it. What is the deal??
Alberto

 

[dgasmd]

Anyone??

 

[erasmu]

I don't know about the pinout difference. In fact, my bulbs are 4 pins in a row .... and 65 watts. I don't know how hard it will be to find replacements for mine. 55s and 96s seem so much more commonly stocked. Everything I have read seems to indicate that PC bulbs do not need to be changed as frequently. The recommended interval I have seen is 12-14 months. I plan on making it an annual event for my tank.

 

[suckair]

Bulb replacement cycles depend on the quality of the lamp and the ballast. I have VHOs on IceCaps that are well past 24 months old with no discoloration on the ends. I have not taken a light meter to them and have no starting point of refrence but they sure do look bright to me!

I don't know the difference between the 4 end and 2 end. Perhaps both sides of the lamp are on the one end. I have seen some compacts that had the ends coupled together so the gas could get thru and the socket on only one end! Perhaps you are looking at both sides of the lamp on one side

and that is the socket design. I have never run compacts and don't have much experience with them. My buddy Ray has them and his ends are 4 plugs. I know in a normal lamp that the two pins on one end are hooked up to the same potential.

good luck

 

[MattM]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by dgasmd:
<strong>*What is the light quality diference between the 4 pin ( :: ) and the 2 pin bulbs ( : )?
*Any quality difference between them?</strong><hr></blockquote>

Never seen two pin PCs. They are either four pins in a square (Japanese style), or four pins in a row (European sytle).

FYI, "Japanese style" is from the original manufacturer: Panasonic, but if these are from HelloLights then they are of Chinese manufacture. "European style" is from Osram/Sylvania.

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by dgasmd:
<strong>**Also, I was told by someone that VHO bulbs should be changed every 6 months because the light quality degrades enough by then. They also said that PC bulbs should be changed every 6 months as well. Is this true? I had heard from so many other places 9-12 months for PC, but this guy is very adammant about it. What is the deal??</strong><hr></blockquote>

PC's will last 24-30 months with a normal 8-10 hour on cycle. However, there is considerable loss of output. We have verified this with a lux meter. You should replace at 12 months - you will see a noticable jump in brightness when you do.