mechanical pwm

So I was racking my brain to figure out how to incorporate a pwm into my system useing the electronics on my truck i.e. points coil etc.Anyway to no avail.But I found something else lying around the shop and decided to give it a try.Tried to post a photo but my camera isnt working.I found a mechanical device I took off a sign that flashed.It has two sets of contacts and is completely ajustable as far as intervul etc.It works great.Iknow there is a slight risk from the very small sparks created by rhe contacts but I will encase the device in a wood box and I think that will take care of the problem.Part of the reason for using it is it 's free but also having a tough time sorting through what not to buy.It's very cool and works great!I can finally justify not throwing something away.

PWM off a blinking arrow.

I need some one to tell me why I have trouble with Pwm getting code E01 on my unit when the cell has no shorts what really concerns me is water is a great ground how dose the PWM get around that?

Does the water have Electrolytes?
Check your connections.

i think you do not need a pwm if the cell is bult right im new at the forums and no disrespect to all i been doing this hho stuff for 5 years and spent over 70k on it and having fun with it but you will need a big alternater like 350 or 420 and the right kooling system look at my youtube (jaimemarcial69)and see for yourself i think a pwm is worthless if you cant go over 200amps but i am willing to try anything that works looking into a golfkart speed controler for bigger cell like the one i have in the video 55 plats.the alternator will cost about 500 to 700 it worth it hope this helps jaime out