# Battery based DC motors

I am looking into building a motor controlled lift.
I need it to be portable.
The motor I have in mind may draw 30 Amps under full load.
I have read that a voltage boost regulator is a good thing to have between the battery and the motor.
So, my question is:
Where can I find a 12-14V in, 12V+ out at 30+ amps boost regulator??
donald
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Donald wrote:

I wouldn't say that is an absolute.

If you need to regulate the speed then you may want to build a motor amplifier, at that current, PWM. Otherwise, if you don't need to control speed, just use a high current relay.
A "boost regulator" may be usefull if you want to make the motor go faster than it would at 12V. Torque of a motor is based on current. The voltage required to drive a motor at a specific speed must be higher than the back EMF of the motor at the desired speed.
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Donald wrote:

What are you expecting from a regulator? You're not going to get out more power than you put in.
John Nagle
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
John Nagle wrote:

I would like to speed control the motor involved.
As the battery gets low, I can keep the speed constant.
Or am I totally off base !!
Donald
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
John Nagle wrote:

That is "true" in the purest sense, but a "boost regulator" can increase the voltage, thus raising the point where you reach equilibrium with the back EMF of the motor, allowing the motor to spin faster (assuming you have not exceeded the capacity of the power supply). Obviously, the boost regulator will use more power than a batter connection because a boot regulator is not 100% efficient and the motor will be spinning faster than it would under direct power.
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
hai donald, its better u buy that boost regulator