Maker Pro
Maker Pro

need guidance making a voltage regulator

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
hello. i'm new to the forum.
i tried 4 different forums, and the usual useless Reddit. no luck.
alright so i have a chinese scooter with a regulator rectifier ( if that bugs you down because tis a vvehicle, lets say i have a solar panel or windmil or whatever producing its power.... ). it produce NO ac only DC ( 7 wire ).
the white wire is unregulated and used for the automatic enricher ( basically a heating element heating wax so it extend or retract a needle ).
people use this wire to power headlights since its a 12v output. i tried, and it blow the bulbs and leds.
after verification ( i should of checked that first... the nosense crap people say sometime............. ) it end up bein unregulated.
so its from 8 to 50+ volts depending on engien rpm.
well, that isnt gonna work out. so i tought maybe they just forget to tell they use automotive relay.
it lasted 2 days. i put one of a better quality, lasted 3 or 4 days.
yup. same. it aint gonna work, voltage goes too high.
so... i need to build ( or buy, its its a decent solution ) a regulator that will regulate to aprox 14 to 15v ( yup automotive/motorcycle electronic equipments says 12v but they're made to run on 14.7v since its the charging system voltage ).
ive found guidance on how to go from 12 to 5v and things like that, but nothing i need.

its gonna run 2 headlight led bulb, and also stop/running lights ( full leds. its 2023 duh ) and underglow led stripe.
i need this so headlight comes on only when engine is running. like it originally was but on AC power.
when i have to work on it, it jsut drain the "way too small original battery of 8ah".
the total amp draw is under 10 amps for sure. probably around 5 or 6, but the only thing i know about electronic is its better to make it support higher amp than needed.

thanks.
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
A buck-boost converter will take 'any' DC input and output a fixed DC voltage of your choosing regardless of whether the input voltage is higher or lower than the required output.

Many buck-boost converters are rated in watts so at a 12V output and 'around 5 or 6 amps' you need a buck-boost converter rated at 100W (or more).

Here's a typical eBay link https://www.ebay.co.uk/itm/31413017...vYP5TjFqjGLv/NMt/Oa7ySOZkg==|tkp:BFBMhM-AuJxi
 

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
thanks.
yeah ive seen those.. but they says 8-40v input. my votlage can reach 60v ( thats what ive seen but the stator produce up to 80-85v at 8000 rpm so its probably around 80v on the white wire. multimiter read 60v but maybe its just too slow ).
unless its "suggested" and can handle way more than 40v input ?
 

danadak

Feb 19, 2021
797
Joined
Feb 19, 2021
Messages
797
A post I posted on wrong thread, could not find erase button.

Regards, Dana.
 

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
Perhaps a unit like this would work.
thanks.
thants not a reasonable option.
its huge, and difficult to protect.

after re-thinking ( damn adhd ), i do not need such amps
i only need to drive an automotive 12v relay ( less than 1 amp ).
this way the lights will take juice from the battery but only when the engine is running.
any suggestion for a unit like that ( still need like 12 to 80 volt ) with +- 1 amp ?
or a guidance on how to build one ?
 

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
zener diode to limit voltage ??????
i dont know electronics much, but a zener diode is like a one way valve it let current flow only one way. nothing to to with limiting the vltage ?
as i said i know how to build a rectifier.. but not a voltage limiter as i need it.
 

Delta Prime

Jul 29, 2020
2,133
Joined
Jul 29, 2020
Messages
2,133

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
thanks alot. didnt know it could be done with zener diode.
i have yet to understand why min voltage an max voltage seems reversed ( i want 11 to 90v so i enter min voltage as 11 and max as 90, all calculato say min voltage inpt too low. it worls if i reverse min and max input voltage ? )
 

danadak

Feb 19, 2021
797
Joined
Feb 19, 2021
Messages
797
No on reversing.

Go to page 31 and it talks about min/max usage and why a min or max is
used in the calculations.

Regards, Dana.
 

Attachments

  • HBD854-D.pdf
    374.8 KB · Views: 3

br4inl3ss

Jun 22, 2023
7
Joined
Jun 22, 2023
Messages
7
thanks. i have a friend that can translate this to me.
math is far from bein my thing. really far. so those maths and symbols is chinese to me.
 

Delta Prime

Jul 29, 2020
2,133
Joined
Jul 29, 2020
Messages
2,133
And be careful with those zener diodes at high voltage they are prone to thermal runaway.
Research pros and cons of zener diodes used as voltage regulators
 
Top