# Ballast and Lamp Wattage Matching?



## waynet (Apr 22, 2010)

Hi:

I have a IG13-20EL Ballast that is suitable for these lamps: F14T8, F14T12, F15T8, F15T12, F17T8, F18T8, F20T8, F20T12, or FC8T9(22W)G10q lamp.

This ballast came with my 10g tank and a 15" 14W T-8 Florescent lamp. Unfortunately, the ballast has burned out. I have another ballast from Sunpark that has a CFL socket and the ballast is suitable for CFQ18W, Quad, F17T8 (17W), CFT18/2G11, FT18 PLL lamp. For the Sunpark ballast, the CFL tube has burned out. It is hard to find this CFL tube and it is very expensive (over $45 after tax).

So I am wondering anyone tried powering a slightly lower Wattage Lamp (14W) with a ballast for 18-20W?

Both Ballast is for 120V 60Hz. What I find out is that ballast is a current limiting device. Ballast and lamp should generally be fairly close in Wattage, Lenth and Diameter.
So for I (Current) of the two ballasts.

What I know is I (current) = W (Watt) / V (Volt). So 17/120 = 0.1416 AMP vs 14/120 = .116 AMP. The difference is about 0.0256 AMP

For a human, a current of 0.06-0.1 AMP can be deadly:

"At currents as low as 60 to 100 milliamperes, low-voltage (110-220 volts), 60-hertz alternating current traveling through the chest for a split second can cause life-threatening irregular heart rhythms. About 300-500 milliamperes of direct current is needed to have the same effect."

I touched the Tube, I did not notice it is that much hotter than my other 14W lamp. Anyway, I am going to only have this lamp on when I am at home. For sure, I believe my lamp life-span will be shorten. By how much I don't know.























Thanks in advance.

Wayne


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## Dietmar (Dec 15, 2011)

I do not know about matching the lamp to ballast.

However I have a 546-B-TC-P spare ballast.
Trigger start ballast
for one F20W T12
F15W T12
F15W T8 
F14W T12
PREHEAT START LAMP
Seems this ballast is good for 20, 15, or 14 watt lamps.
Its available if you need it. Have anything to trade?


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## waynet (Apr 22, 2010)

Thanks for the offer. I think for now it appears to be ok. The lamp is not heating up like crazy. I am just looking for other peoples' experience with ballasts.


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## waynet (Apr 22, 2010)

At least the light is working well so far. I guess the small difference in wattage didn't matter. I only turn on the light when I am at home anyway.

I got tired on sharing one 15" light between two 10g tanks for two months. I had to put the light at the top tank for a few hours, let the light rest, and put the light at the bottom tank a few hours. At least I am making use of the unused ballast now.


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