[StirCrazy]

Originally Posted by ldzielak

Why series? Do the bulbs not run with 2 reds on each? Your still only going to get 220W from the balast. I don't have another WH7 now to play with, but I'm thinking of replacing my Tar unit with a WH7 to maybe prolong bulb life. I don't need the tank any more blue.

Lee

the output of the bulb is dependent on the current through it for its length not the wattage of the ballast.

so if you use 2 wires you will get current levels that HO ballasts produce.
this amount of curent will power VHO tubes at about 65% of there rated output.

to get the full curent required to power a VHO tube you need to use 3 wires to one bulb. sence you can only hook up one bulb this way if you have two you have to use the series method to creat the ilusion of running one bulb. so if you use two 36" VHO bulbs then it will power at full curent to the full 190 watts. if you use two 48" VHO bulbs it will power to the full 220 watts.. this is why it will not work properly with say two 5 foot bulbs.. the power requirment would be higher than the ballast output so it might not light and if it does it might kill your ballast early.

IceCap clames that by using two wires and driving at HO levels (they don't admidt the do this, but tests have showen that the IceCap output is identical to a HO ballast) that you extend the life of the VHO.. this is true in part.. the big part of the life extension is the starting of the electronic ballast.. it is much easyer on the bulbs that the start a Tar ballast gives.

I have proven this my self with NO bulbs on my freshwater tank.. 2 years of running 10 hours a day and only a 10% drop in output. I was going through NO bulbs every year befor I went with a electronic ballast.

so I gues sit is up to you.. if you want your 110watt VHOs to output only `70 watts then use two wires.. if you want the full power from the bulbs then use the 4 wires and put them in series. after all why did you buy VHO's if you are only going to use them as HO's? would have been cheper to overdrive NO's to HO levels.

Hope that helps

PS. for got to address something you said Lee.. if you replace you tar (which is running at full VHO levels) with a WH7 running at HO levels you should get a little less blue.. this also might be hard to notice as the frequence of the electronic ballast also enhances the light which is good for about a 5 to 10% increas in light output in its self.. (also one of Icecaps tricks) so what I would do if I was in your place is try them in series.. if you find it to blue after a couple days then rig them with 2 wires each and see if you like it that way..

Steve