<div id="RTEContent">Possible... but using a lamp like that would be a huge hit in<br> system reliability. Lamp can burn out / damage from vibration.<br> <br> next ? :^P<br> <br> H^) harry<br><br><b><i>Oren Leavitt <obl64@ix.netcom.com></i></b> wrote:<blockquote class="replbq" style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"> You might try a simple 12V incandecent lamp in series with the solenoid <br>coil.<br>The inrush current to the cold lamp will give the coil the full 12V <br>"kick" it needs to start. As the lamp warms up, its resistance will <br>rise, resulting in reduced voltage across the coil.<br>Choose a lamp the settles to your desired 6 to 8 volts.<br><br>Hope that helps,<br>Oren<br><br>Nick Liebrecht wrote:<br>> Hi all,<br>> <br>> I need to make a circuit to protect some solenoids in a flow cell from <br>> getting too hot. Basically, I need to apply 12V to the solenoid coil <br>>!
for
about 100ms, and then bring it down to about 6 to 8V. I measured <br>> the maximum current through the solenoid to be around 225ma. I was <br>> thinking of using an ADSR to create the proper voltage transients, <br>> followed by an emitter follower (using a PN2222A, Ic=500ma) to provide <br>> enough power to actuate the solenoids.<br>> <br>> I need six of these, and i was thinking of using the ASM-1 ADSR as a <br>> starting point, replacing all the pots with the appropriate resistor <br>> values for the timing and sustain level I need.<br>> <br>> Does this sound like it will work???<br>> <br>> Thanks,<br>> Nick Liebrecht<br>> nick.liebrecht@gmail.com<br>> <br></blockquote><br></div>