A Forum run by Enthusiasts of MidNite Solar

General Category => General Discussion => Topic started by: Ron Swanson on November 07, 2019, 10:59:04 AM

Title: 12 volt -> 9 volt Power Supply for Alarm System
Post by: Ron Swanson on November 07, 2019, 10:59:04 AM
A customer wants us to come up with solar power backup for an alarm system.

Right now it is powered by a 9 volt wall wart.

We would need some sort of *reliable* converter from 12 volts to 9 volts, everything else can be done with standard hardware.

The power supply says 0.7 amps.
Title: Re: 12 volt -> 9 volt Power Supply for Alarm System
Post by: ClassicCrazy on November 07, 2019, 11:29:35 AM
There are lots of dc to dc buck converters out there on ebay .
I use $2 ones here that are adjustable output - never had any problem with them .
Of course those are the inexpensive chinese ones but sure if you want some kind of name brand those are available too.

Larry
Title: Re: 12 volt -> 9 volt Power Supply for Alarm System
Post by: Ron Swanson on November 07, 2019, 03:45:15 PM
Is there a manufacturer out there whose products can be recommended?

That's kind of what it boils down to, this has to be supported by somebody.  To be a professional solution.
Title: Re: 12 volt -> 9 volt Power Supply for Alarm System
Post by: ClassicCrazy on November 07, 2019, 06:55:52 PM
Quote from: Ron Swanson on November 07, 2019, 03:45:15 PM
Is there a manufacturer out there whose products can be recommended?

That's kind of what it boils down to, this has to be supported by somebody.  To be a professional solution.

Look on Digikey - use filters to select your options for DC to DC converters  https://www.digikey.com/

This place also has filters to narrow down selections  from https://www.perle.com/products/industrial-power-supply/#undefined
Title: Re: 12 volt -> 9 volt Power Supply for Alarm System
Post by: boB on November 07, 2019, 09:10:53 PM

When you say 12V input and 9V output, what input voltage range and how good of output voltage 9V regulation do you need??

Will the 12V be coming from something as wide and varied as a car 12V system ?  Say, 11.5V to 14.8V or so ?

And will the 9V need to be 9.0V +/-  0.1V ?   +/-  0.5V ?   or something different ?

boB
Title: Re: 12 volt -> 9 volt Power Supply for Alarm System
Post by: Ron Swanson on November 08, 2019, 11:36:32 AM
12 volt would be coming from a Midnite charge controller on some kind of AGM battery

9 volt is now being supplied by a cheap wall wart so regulation probably not critical