Take a look at this..

SD on 13/10/2004 at 23:02

What you are trying to do is essentially impossible. Effectively, you want to have Constant Effect Absorb 100pts Health from everyone within a 50ft radius! There is no item in the game that could even come close to holding that level of enchantment, and I doubt very much whether you could ever raise the kind of money necessary.

Constant Effect enchantments normally apply to oneself, and are useful for such things as Fortify Attribute, Levitate, Restore Health, Bound Items etc. Nice items to put CE on include Exquisite rings, amulets and shirts and Daedric armor (I have Fortify Strength 45 pts on my Daedric Towershield :D)

If you're looking to enchant your weapon with Absorb Health, by far your best bet is to have it Cast on Strike ie when you hit the enemy with your weapon.

SD

Karraz on 13/10/2004 at 23:05

"set the magnitude from 100 to 100
and area at 50

I selected constant effetct, now the spell says "on self" which I dont understand.

Furthermore, the price was ridiculous... almost 4 billion gold...

So I guess I did something wrong..."

It would seem so. A couple of things, keep an eye on the upper right corner as you adjust the magnitude and area. You were trying to excede the capacity of the enchantment. Try a magnitude of 20-50 and keep the area low around 0-5. For the absorb health you are putting on the sword I woud not use constant efect. Use the "on strike or hit" that way you don't actually use the charge until you've had a successful hit.
I use the constant effect for exquisit robes and such enchanted with sanctuary, camelion, sheild, atrib boosters, or stuff like that and then have it apply to "on self".
If you are not sure what to do, save the game and then experiment. That way if you screw it up, restore the game and try again.