24VAC to 12VDC converter

[cglaeser 0]

I have an Altronix 24VAC power supply used for IR Illuminators and want to add a couple PIRs that are spec'd between 6-18VDC. When converting 24VAC to 12VDC, do you have any favorite converters?

 

Best,

Christopher

[Soundy 1]

They're called "voltage regulators" One of these fits nicely inside most Altronix cans: http://www.electronicproductonline.com/catalog/product_info.php?products_id=1770 (sorry, yes, it's a store link - I can't find a manufacturer's page).

[CCTV_Suppliers 0]

The only one that I know that works well is this one: http://computarganz.com/product_view.cfm?product_id=291

[Soundy 1]

It's not a complicated circuit, really: a bridge rectifier, a couple filter caps, a voltage regulator IC, a heat sink, and maybe some voltage-divider resistors if you want to make it adjustable output...

 

http://www.circuitstoday.com/fixed-positive-voltage-regulators

 

 

[cglaeser 0]

Thanks, that's very helpful. I also found the Altronix VR series (VR1, VR1T, VR2T, ....).

 

Best,

Christopher

[ak357 0]

Thanks, that's very helpful. I also found the Altronix VR series (VR1, VR1T, VR2T, ....).

 

Best,

Christopher

 

Any 24 V old, broken camera has inside 24 to 12 V converter

if u electronically incline person should be very easy

[rory 0]

They're called "voltage regulators"

Not to be confused with a Voltage Regulator used for power protection.

Traditionally "Voltage Regulators" are boxes that plug into the wall before an electronic device and provide automatic voltage regulation, such as those from Tripplite and APC.

[Soundy 1]

Traditionally, a "voltage regulator" is ANYTHING that regulates voltage, AC or DC, single component or complex circuit.

 

This is a voltage regulator:

 

As is this:

 

And these:

 

This is one too:

 

BTW, Tripp Lite doesn't have any products that they list as "voltage regulators". Their site lists Uninterruptable Power Supplies (aka UPSs or battery backups), which I believe is what you're talking about, and Surge Suppressors (among other things), but nothing that's specifically marketed as a "voltage regulator".

 

APC lists UPSs and "Surge Protection and Power Conditioning", but nothing that they actually call a "voltage regulator".

[rory 0]

BTW, Tripp Lite doesn't have any products that they list as "voltage regulators". Their site lists Uninterruptable Power Supplies (aka UPSs or battery backups), which I believe is what you're talking about, and Surge Suppressors (among other things), but nothing that's specifically marketed as a "voltage regulator".

 

APC lists UPSs and "Surge Protection and Power Conditioning", but nothing that they actually call a "voltage regulator".

 

No, im not talking about a UPS, Im talking about something that protects. Current gets too high, it stops it, current gets to low, it stops it, in other words the outputs are disconnected. A really huge spike of high voltage will fry this, but the devices connected to it are fine, as happened to one the other day.

 

Some, not all, UPS have Automatic Voltage Regulation built in, but I prefer to keep it separate even then. "Voltage Regulators" are also half the cost of a UPS and in most cases a UPS is never needed or is useless due to the short backup times most consumers can afford. Additionally I have found a UPS not to provide power sometimes when the electricity comes back on, although rare its a problem when the customer wants their system running 24/7 and nobody knows until days later. Also basic surge protection is useless in most cases. Dont get me wrong there are cases where a UPS is invaluable, such as when developing software or using other certain apps that when the system crashes the file being used is corrupted beyond repair, or ofcourse just never saved.

 

This is a voltage regulator: These suckers protect against some really tough brownouts and spikes, proven almost every day here

http://www.apc.com/products/category.cfm?id=12&subid=57

 

Tripplight calls them line conditioners, I had one of theirs for over 10 years.

http://www.tripplite.com/en/products/product-series.cfm?txtSeriesID=838

 

We use "Voltage Regulators" religiously down here, not having a "Voltage Regulator" is like not having a roof on a car.

 

I guess I should have been more specific, as in "Traditionally" I meant in the PC and CCTV industry, and more specifically on this forum, thats what we know a Voltage Regulator as, but yes as with many things there are more than one type. But basically I only posted to let people know that this was different from the other Voltage Regulators we use every day.

[rory 0]

This is one too:

Sure, I have used those same models, but they are rubbish compared to the APC units.

 

APC loves selling their VRs to their latin america clients like us (yes to the US, Caribbean is latin america) as we get to really test their products in the real world in ways they might never be able to.

[Soundy 1]

I guess I should have been more specific, as in "Traditionally" I meant in the PC and CCTV industry....

Here in Canada, at least, a "voltage regulator" in CCTV means the thing that gives you a clean 12VDC instead of 16-17VDC out of a wall-wart....

[rory 0]

I guess I should have been more specific, as in "Traditionally" I meant in the PC and CCTV industry....

Here in Canada, at least, a "voltage regulator" in CCTV means the thing that gives you a clean 12VDC instead of 16-17VDC out of a wall-wart....

Yep, I guess 2 different things though somewhat similar. But the one I meant is the high voltage version with protection, something the wall-wart (and everything else) plugs into, without this the wall-wart wont last here, and in many cases why it fails in other places also but on a lesser scale. In other words this Voltage Regulator protects your equipment, and also regulates the voltage. As mentioned many UPS have the AVR built in as well, but the VR is the most important part as without that, wont have anything left to backup. Basically its a line conditioner, but APC calls it voltage regulation and thats one of the most popular. IMO without a voltage regulator, such as this, I dont think anyone should complain when a hard drive fails. Ive yet to see one fail when its on one of these, after 15 years of using Tripplites and APCs. Although Ive seen hard drives and other parts fry all the time without them, even with UPS they fail all the time, unless it has AVR (Automatic Voltage Regulation) built in, which some do not. Ofcourse if a location is completely Solar or has an entire building line conditioning system then there is no need for these. If they never have brownouts or voltage spikes then also there is no need for this, ofcourse anytime the power goes off and comes back on though there is the chance of a brownout or too much voltage depending on how good their electricity source is there, here it sucks.

 

We've talked about these Voltage Regulators for years on this forum though which is why I felt I should clarify the difference from the one you mentioned, thats all.

 

ps. my lights been dipping all night tonight, the APC Voltage Regulator protected me each time, there is a clicking noise it makes when it detects too high or too low voltage and it adjusts, if it is too much either way such as in a full blown brownout or over voltage then it cuts the power.

[rory 0]

Here in Canada, at least, a "voltage regulator" in CCTV means the thing that gives you a clean 12VDC instead of 16-17VDC out of a wall-wart....

BTW whats a 16-17VDC wall-wart? Do you mean an AC Adapter? If so what type gives 16-17VDC?

[Soundy 1]

Here in Canada, at least, a "voltage regulator" in CCTV means the thing that gives you a clean 12VDC instead of 16-17VDC out of a wall-wart....

BTW whats a 16-17VDC wall-wart? Do you mean an AC Adapter? If so what type gives 16-17VDC?

Have you ever actually measured the output of an unregulated transformer-type "12VDC" adapter? A typical design for a 120VAC-input design uses a 10:1 transformer to step 120V RMS down to 12V RMS... 12V RMS equates to 16.8V peak-to-peak... when you run that through a bridge rectifier and a filter capacitor, you end up with around 16VDC.

 

Regulated supplies add a regulator, typically similar to the 7808 pictured above (for up to 1A output).

[rory 0]

Have you ever actually measured the output of an unregulated transformer-type "12VDC" adapter?

All the 12VDC AC adapters I have used are metered at 12VDC output.

I have 6 different shaped ones sitting on the table now and all are 12VDC max output.

They range from 500ma to 2amp. Ive never used a 12VDC adapter at 16/17VDC.

I have a 2amp 12VDC one spliced powering all 4 of my cameras as we speak.

Are we talking about the same thing?

[Birdman Adam 0]

What he's saying is that even though it says 12VDC on the rating, if measured with no load on it, it will show ~16VDC. These should still be fine for powering 12VDC devices, because once they are put under a typical load, the voltage sits at 12VDC.

 

Here's a great article that talks all about wall-warts:

 

http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=103

[clearsignal 0]

I think what Soundy is saying is that if you crack that wall-wart open, you'll likely find that 16V somewhere between the rectifier and the regulator. The output, if regulated, should be at 12v.

[rory 0]

What he's saying is that even though it says 12VDC on the rating, if measured with no load on it, it will show ~16VDC. These should still be fine for powering 12VDC devices, because once they are put under a typical load, the voltage sits at 12VDC.

 

Here's a great article that talks all about wall-warts:

 

http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=103

Maybe with some but all I use are still just 12VDC with no load.

Come to think of it though now that you guys mention it, I do recall one a few months back with 16VDC, threw it away and used one of the others I had. Thats the only one I ever saw with that voltage ever since Ive been doing this. I always meter a 12VDC plug before connecting it to check wire polarity. Its good information to know for the future though, but Id just chuck it if it is not 12VDC and use another.

[Soundy 1]

ANY transformer-type will read ~16V unless it's regulated. Doesn't mean there's anything wrong with it, that's just the way they work. We used them like that for years... most of the ones that come with cheap cameras are the same. It's not a big deal, because most "12V" electronics are designed with tolerances to account for the "overvoltage".

 

For the most part now, we're using switching-type adapters, which are inherently regulated, and tend to be smaller, lighter, cooler, more reliable, and cheaper.

[rory 0]

ANY transformer-type will read ~16V unless it's regulated. .

Then I guess that means everyone (but that one) Ive used in the past 10 years has been regulated. Its good to know I dont have to chuck the rare 16VDC one I do find though Still regulated or not one should plug that into a Voltage Regulator to protect it and the device

[Soundy 1]

I guess I shouldn't say "any"... 9VAC RMS would rectify to 12.6V P-P, so some may be designed with a 9V transformer instead.

 

Either way, variations in INPUT voltage will still be translated to variations in output voltage, unless the unit specifically says it's regulated.

[rory 0]

I guess I shouldn't say "any"... 9VAC RMS would rectify to 12.6V P-P, so some may be designed with a 9V transformer instead.

 

Either way, variations in INPUT voltage will still be translated to variations in output voltage, unless the unit specifically says it's regulated.

 

Ok thanks, good info