It’s the S guy again asking questions about my Geiger 19 inch turntable. I am looking for a power supply or transformer to power the 12 Volt DC can motor for this turntable.
I have pasted below a link to a power supply I found on ebay, and am hoping someone can tell me if this is sufficient for my application. It seems to me that a DC trnasformer would be overkill, since I don’t see any additional need for DC power on my AF all ac layout. Or if anyone has an idea for another solution, please let me know.
That power supply is only a 1/2 amp. As you are in S scale, I assume the locomotives are in the 2-5 lbs range, I think I would be more comfortable with at least a 1 amp (1000mA) supply. Radio Shack has some 12v/1A wallworts.
Hi and thanks for the response. As Ned states in the next post I am just looking for a power supply for the 12 V DC can motor that operates the turntable, but also as you noted the locomotives do weigh 2-5 pounds. I think what you are suggesting is the little can motor may need more that 200 MA power supply to carry the load. And that is exactly the question I am struggling with.
I don’t want to fry the motor with too many amps, but there just isn’t any detailed requirements in the instructions, other than 12 volts DC.
Ned,
Thanks for your response also. I think I will get a 1 amp unit and give it a try.
You can;t fry a motor with too many amps. The motor will only draw what it needs. You can use a fuse rated just over the motor’s maximum current draw to protect the motor and the power suppyl in case of a catastrophic failure of the motor - such as it shorting otu completely, but if that happens the motor’s already fried. The fuse will cut the power though and prevent the motor from heating up, and also protect the power supply from damage. But a 5 amp power suppyl is not going to ‘pump’ 5 amps into a 1 amp motor.
The exception to this is LEDs, because they are current devices, not voltage devices. It IS possibel to put too much current into an LEDs, which is why they are used with resistors. The resistors are NOT to reduce the voltage, they are to limit the current.
Thanks for the education, that helps me quite a bit.
What I have done is purchase an HO transformer capable of producing varaible DC voltage up to 16. I have also purchased a 12 volt DC 1000 MA power supply. I can work with both of these units and determine what works the best.