×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

amp control question

amp control question

amp control question

(OP)
i have a bank of 12 V batteries, charged by solar cells, that i want to run a wireless camera with.the cam requires 12 volt 80 mA source.i also have a receiver that requires 500 mA at 12 volts,that will be seperate from the camera. what is the best way to control the amp problem so they don't fry.appreiciate  some advice-this is not my speciality.thanks

RE: amp control question

As long as you provide 12V to each device, each one will draw only the current it requires and everything will be fine.  Not sure how you plan to wire this, but each device needs to connect to the + and - of the twelve battery - they are in parallel.

RE: amp control question

You use 80 mA for your camara and the reseiver 500mA.
This is a total of 580 mA that is possible to take from one battery.
The supply wires of the differend units needs to go directly to the battery, in this there is no influence of the differend currents.
This is only if the impedance of the battery is low.
If the impedance of the battery is high the voltage drop will be greater and the charging from solar cells will be higher, this not danger for your Scells because the impedance of the cells.
It could happen if the battery will get a short but if the battery is low there the impedance gets higher and limits the current.

RE: amp control question

I would put in some extra fuses as well. They likely have there own internal fusing but worth checking out. Buzzp

RE: amp control question

You need a simple linear low drop-out regulator.  Since you are also charging the batteries from solar cells, your voltage will be up around 14.4 volts or so, assuming you are using some type of charge regulator.  While the camera and receiver may operate for a while at this higher voltage, it will definitely shorten their life expectancy. You can find these regulators in places like Digi-key or Mouser for a dollar or so.  Get a datasheet for the device you select and follow the application notes.  Don't you a switching regulator, or you may find your receiver swamped with switcher noise.  Hope this helps.

Lewis

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close