I got a cheap enclosure for PATA drive data transfer (to the PC), and it has no fan cooling, or venting, for that matter.

I want to tap the Molex connector in the enclosure, for power to a tiny 12V fan (amp draw = 0.06A).

Will the drive (WD 250G PATA) leave enough power for the fan?

The enclosure PS A/C adapter says:
12V = 1.5A
5V = 1.5A

The drive label says:
5V (insert funny symbol ???) 0.65A
12V (insert same funny symbol ???) 0.65A

I hope to keep the MAGIC SMOKE inside of the circuits!!! Once it gets out, nothing works...

Hey, that's it, smoke and sand.

A WD Caviar (80Gb) lable has these details...

so, that current draw...

12VDC @ 0.50A + 0.65A = 1.15A

so you have about 0.35A to play with.

IMHO, It should be OK to try.

I have one addittional thought about current draw and voltage regulation,

The fan will consume any current it can source,
where as the HDD has a power reg built in, and
the hdd will fault if it can't access the current
required for the circuit board and motors.

Watch out when (and if) the fan gets dirty, it will draw more current.

Regards Glenn

Hi

A word of caution here.
The fan requires a peak in rush current when it starts to rotate.
That may exceed 60mA (even though 60mA is the max current stated on the fan)

Typ. Specs.
WD 250G IDE 2.5" WD2500BEVE SCORPIO BLUE, 250GB, 5400RPM, 8MB, PATA, 2YRS
Electrical Specs
5VDC : Current draw :Read/Write 500mA; Idle 400mA; Standby 60mA; Sleep 60mA

It appears that 12VDC supply is not used by this drive.
If you are using a 12VDC fan (60mA stated), and the features on the enclose draw little current, then the 12V 1.5A supply should be more than adequate.

On another note, simply adding a fan to an enclosure is not a whole cooling solution. The fan is used to create airflow over the surfaces of the hard disk, and to expel as much hot air from the enclosure (drawing in cooler air from outside the enclosure) as is necessary. So consideration must be given to the physical placement of the fan, the path the airflow is to take, and disruptions to that path posed by cabling, and other obstacles within the enclosure, and the air flow rate offered by the fan, and the airflow possible through openings in the enclosure.
Therefore when selecting a fan it is important to consider fan: size, design (ie. bearing type, brush-less, etc), flow rate, pressure, and electrical requirements.

Selecting the wrong fan is a waste of time, and it's almost never a case of "any old fan will do".

Hope that assists.

Regards

C.

The 5V line has more current available, upto 10 amps or more.

Air circulation is important, but any extra air-flow will usually help.

ref. POWER_FROM_PC.HTML (website nolonger available, circa 1997) Quoted here for prosperity...
I've used pc powersupplies to test and run many electonics devices I've made. I couldn't of done that with out this pc-power-supply knowledge. Many thanks to Tomi Engdahl.

Hope this helps... regards Glenn

Hi,

The OP is not using the system PSU. External unit with external power supply unit.

BTW, I suggest you replace the vbcode tags 'quote' to 'code' thus cleanup presentation. No one likes to scroll through a quote this long. Someone wishing to read will use the provided scroll bar.

@OP Simply adding a fan may not solve the flow through the enclosure. You do need 'free air' flow. Inlet & outlet for good flow throughout the enclosure. Most fanless systems do provide some free flow but most depend on transfer via a exhaust port. Be sure the enclosure does provide sufficient flow when you add the fan.