Maintain current

[h2ocommuter]

I did a mockup of your pencil drawing if anyone wants to copy the design.

I apreaciate this pic. I am bad enough with the scamatic in front of me, the pencil pic. was omg.

I'll get the parts and give it a try.

Thank you too ridealong..

[Keith's Garage]

First off, Thank you so much for coming up with this circuit. My only issue is that the ground wire and the current sense resistor are getting really hot. I am testing this circuit on a breadboard and these two wires are getting so hot that they are melting the breadboard. Any ideas?
Thanks

[sp1r0]

Breadboard's are good for prototyping but are good for MAYBE 2 amps. Sounds like you should go on to building this thing with high guage wire with short distance between connections.

[ridelong]

Keith's Garage,

You built it COOL!

The power resistor is going to get hot, but not hot enough to melt solder, it's the nature of the beast.

The power stuff (HHO wires, fet, current sense resistor, etc) should be 10 ga. wire. Solder them solidly for good connections. Look at my original post with the link to the schematic, it has some additional info on it.

[Jaxom]

RideLong....PM'd you about part numbers.

[h2ocommuter]

Kieth, thanks so much for helping could you send a pic. so I could see how to lay it out on a viro board or whatever kind of board it needs.

I am just learning and it would help if I had an example to see.

failure is not an option for me to learn what I am doing.

I am the only dog trying to eat this elephant.

[ridelong]

Here is a parts list for the current feedback pwm, and where to get.

PART DIGI-KEY P/N COST
-------------------------------------------------------
12 VOLT ZENER 1N5349BTPMSCT-ND .40
500 OHM POT CT2201-ND 2.71
LM339 LM339NFS-ND .47
FET IRL1404ZPBF 3.67
20 OHM 20.0XBK-ND .50
20 K OHM 20.0KXBK-ND .50
49.9K OHM CMF49.9KQFTR-ND .30
(2) 24.9K OHM CMF34.9KQFTR-ND (.60) .30
1 K OHM CMF1.00KQFTR-ND .30
133 OHM CMF133QFCT-ND .30
.01 UF 1460PH-ND .17
10 MEG OHM 10MQBK-ND .27


PART MOUSER ELECTRONICS P/N COST
------------------------------------------------------
.01 OHM 25 WATT 71-RH25-0.01 3.76

[hydrotinkerer]

I apreaciate this pic. I am bad enough with the scamatic in front of me, the pencil pic. was omg.

I'll get the parts and give it a try.

Thank you too ridealong..

Didn't someone forget on the redraw (left of page 12volt zener 1/2 watt) or did I miss something?

[Jaxom]

Thanks for the parts list...that'll make things much easier.

[h2ocommuter]

Can someone help me out on this one.

I ordered the parts to build three of these today and realized I didn't have the knowledge of where the temp probe is comming from in the circuit.
Next rereading everything here two more times I cannot figure out if the hydroxy cell gen. is fed equal 12v from the battery and that same 12v from the battery feeds the pwm circuit?
or if the lower wire (the D wire from the FET) comming from the gen is actually the temp probe for the feedback or the ground for the gen.

I am a vergin