You actually asked two questions .
1 how is amperage / voltage controlled
2 is it really beneficial to generate all that hydrogen
I will answer the second as it seems the more pertinent.
what you are generationg is HHO not just hydrogen. This is an important difference because if it were just hydrogen then you would lose the benefit of it turning back into water and the subsequent "steam" boost in compression values and cleaning benefits of the system. Although the hydrogen by itself would not mess with the O2 value and would allow for the engine to run without jiggering with the EGR and related systems, you would lose a lot of the potential and possibly all the monetary bennies . Using a variable modification device to re set the O2 action levels in the computer system you may add nearly all the HHO gas you want in place of feul in present HHO systems. You only need to insure that readings sent to the on board feul injection computer or throttle body are low enough in O2 (or that your settings are low enough not to trigger more feul to be sent) but rather less feul ( which you are replacing with HHO.)
Now certainly if you generate enough HHO for an eighteen wheeler and you drive a vw beetle then you are going not to need it all even if you are using pure HHO. But that is a matter of common sense Nes pas?
gabatsns
