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Bixenon solenoid controller

litustim

New Member
Hi all,
I am new here merry christmas to everyone,

I bought a chinese projector lenses and they didnt come with solenoid (beam cutout) controller, while playing with it i discovered they work by this principle:
Two wires, aply 12v to them and solenoid moves, reverse polarity and it moves in other direction, i solved that by making H-bridge but here is the problem, solenoid gets hot really fast that way. So i need your help to make a circuit that aplies 12v to solenoid and after 2sec reduces that voltage to lets say 6v, and when i aply low beam it reverses polarity to -12V and after 2sec reduces that voltage to -6V.

Thank you
 

rjenkinsgb

Well-Known Member
Most Helpful Member
A simple method:
Add a resistor in the positive feed to each side of the H bridge to set the holding current, and add an electrolytic cap across the resistor.

Each time it changes over, the capacitor will provide full current for a short time until it charges, then the resistor maintains the low current.
When it changes back, the other side does the same and that side cap discharges via the resistor.
 

rjenkinsgb

Well-Known Member
Most Helpful Member
I was thinking just something like a 470 or 1000uF cap across the resistor - but that looks to work fine and could be "tuned" for timing with low power presets, rather than changing electrolytics!
 

KeepItSimpleStupid

Well-Known Member
Most Helpful Member
Good for single polarity. But the OP needs a circuit that changes drive polarity.
So, it's a starting point. The TS already has a H-bridge. So, the enable pin gets a PWM signal.

Then you have to play games with rising and falling edges of "direction" that triggers the circuit and changes the polarity.
Still doable.

I actually made 3 different solenoid drivers.
1. Used a big pass transistor and I had plenty of cooling available. Fiber optic Light shutter.
2. Leedex rotary solenoid. Required pulses to a CW coil and CCW coil. No hold nonsense.
3. Slow turn-on. Shutter for a 1000W light source used 3 min off, a few minutes on duty cycle near a $1000.00 USD 1mm thick glass filter.
I didn't want clunking. A factory upgrade removed manual control of the shutter. I used a velleman PWM controller that had slow-start built in.
 
Last edited:

rjenkinsgb

Well-Known Member
Most Helpful Member
Is this any good?
I can't make that out...

Go back to your first schematic and just replace the centre FET at each side with an electrolytic cap, leaving the resistor etc. as is?
Plus you can remove the stuff that controlled those extra FETs.
 

KeepItSimpleStupid

Well-Known Member
Most Helpful Member
yea, kinda did it like Danwvw but I threw in a transistor. I needed a logic level trigger of some sort. i don't quite remember the design, Too long ago.
 

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