Halogen transformer question

[velson]

halogen hum

Can anybody describe a transformer used for halogen lightbulbs (interior lighting). Actually I would use it in a way it wasn't ment to be used... I bought a portable refrigerator based on a Peltier device with a brushless fan similar to computer cooling fans, rated 12V/55W to be plugged in a cigarette lighter jack in a car.
The questions would be: can these halogen transformers be used for this purpose (to power this refrigerating unit)?

 

[vicky]

halogen 50v

HI DEAR,

I DONT THINK SO TAHT ANYBODY USE THE TRANSFORMER FOR HALOGEN BULB WHICH WE USE IN OUR HOUSES

 

[velson]

how to test fluorescent transformer

Well, maybe you don't use 12V bulbs in your house...

 

[xxargs]

12v halogen transformer

Can anybody describe a transformer used for halogen lightbulbs (interior lighting). Actually I would use it in a way it wasn't ment to be used... I bought a portable refrigerator based on a Peltier device with a brushless fan similar to computer cooling fans, rated 12V/55W to be plugged in a cigarette lighter jack in a car.
The questions would be: can these halogen transformers be used for this purpose (to power this refrigerating unit)?

First check if transformer/driver make a 12 Volt DC with multimeter

refrigerator of peltiere-type cannot using AC 12 Volt and burn up after short time.

If lightbulb driver make 12-13 Volt DC, check if make good quality DC with low 50/60 Hz 'hum' (ripple) under load - set your multimeter i AC-mode and measure if voltage is below 1-2 Volt under load (ie. driver have capacitor and/or regulation on output) .

Refrigerator of peltiere-type have lower efficity if feeds with unregulated, no filtering high ripple current 12 Volt DC.

---

You can try make DC from 12 Volt AC-transformer if you using rectifire bridge and big capacitance after bridge for filtering of DC. but check first time so your transformer is not going hot after while of time - trafos load is different if going via rectifire bridge and cap to make DC (make high peak current pulses) compare to feed simple halogen ligthbulb.

remember - voltage after rectifiring must be around 12 -14 Volt DC under load or you fry refrigerator after short time. If voltage after bridge make > 14 Volt (12 V ac * sqrt(2) = 16.97 Volt unloaded) under load, you can try using extra power diodes in serie (circa 0.7 Volt each) with refrigator to take down voltage lower than 14 Volt under load.

 

[velson]

halogen transformer 12v

Thanx xxargs! I'll keep those things in mind. Are you sure though, that the voltage won't drop under the hum level under heavy load if 12V transformer is used?
Should I use a higher voltage input i.e. 15V or so? And if so, do the diodes do the trick in dropping the voltage or is a voltage regulator a better idea?
P.S. If diodes are in series, are they all dealing with the same current (max) or divided by number of diodes?

 

[melc]

halogen electronic transformer dc uses

Thanx xxargs! I'll keep those things in mind. Are you sure though, that the voltage won't drop under the hum level under heavy load if 12V transformer is used?
Should I use a higher voltage input i.e. 15V or so? And if so, do the diodes do the trick in dropping the voltage or is a voltage regulator a better idea?
P.S. If diodes are in series, are they all dealing with the same current (max) or divided by number of diodes?

Why don't you start with telling the power of your bulb ? For a 60W 12V halogen the current will be P = U x I so I = P /U = 60/12 = 5A
You need an 8A or 10 A bridge rated at 50V (there is no lower voltage bridge).
The 12V halogens have a delayed power on circuit using usually triacs. That's because if the bulb is turned off for a short time and then turned on again, the filament will burn in 50% of the cases. Also the turning on is done slwly with variable current from 0 to nominal current. Think how could you desin such a thing.

And yes, in many houses from this world there are plenty of 12V halogen lamp. Do you know why ?

 

[mhtplsh]

12 volt dc heavy load transformers

For halogen bulb i used AC supply. But ur car refrigerator will need DC power supply.
Check the specification of both. Then u can easily add rectifier+filter circuit if the power/voltage (after DC) of the transformer is suitable for refrigerator.