What do you know about Transformer sizing?

I think you've answered your own question.

In answering your question, I watched several episodes of transformers and can share some findings.
It seems normal to estimate the size of transformer needed and send the estimated size of transformer.
Usually this first transformer is undersized, and you send in a bigger transformer to help save the day.
I experimented with thinking what the story would be like if they just sent in the biggest transformer every time (Optimus Prime) and actually the story is significantly less entertaining.

Timeismoney08 said:

I can post the motor data tomorrow, but....

The question was if I need to size the power supply to handle all Motors at the same time even if it will never be turned on at the same time.

It doesn't even have to be a motor...Let's pretend it's a LED drawing 500ma...If I had 10 of them, but only 1 ever turns on at a time...Do I need to size the Power supply for worse case scenario @ 5 amps, even if it's fused properly and my program prevents it? Or can I limit the power supply to handle 2 or 3 LEDs since I know I will never turn them on in the program?

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I would say your question of sizing the power supply to how many motors are running all depends on your control scheme. If all 3 motors are interlocked so one cannot run while the other are, I would only size it for 1 motor.

If, however, they have independent controls and bubba can turn on two motors at once even though he shouldn't, you should size for all motors.

Rson said:

I would say your question of sizing the power supply to how many motors are running all depends on your control scheme. If all 3 motors are interlocked so one cannot run while the other are, I would only size it for 1 motor.

If, however, they have independent controls and bubba can turn on two motors at once even though he shouldn't, you should size for all motors.

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Thank you.

I would protect it in the program from ever allowing it to actuate at the same time. If they use jumpers or force outputs, that's on them.

The circuit protection would prevent any over-current being drawn from the power supply and getting to the crowbar circuit being needed.

AustralIan said:

In answering your question, I watched several episodes of transformers and can share some findings.
It seems normal to estimate the size of transformer needed and send the estimated size of transformer.
Usually this first transformer is undersized, and you send in a bigger transformer to help save the day.
I experimented with thinking what the story would be like if they just sent in the biggest transformer every time (Optimus Prime) and actually the story is significantly less entertaining.

Click to expand...

You bring up a good point. Initially undersizing the transformer will result in more entertainment for casual observers, but the best solution for those with vested interest is probably to slightly oversize the transformer from the start.

you do not say what you application is.
what are the moors connected to?
no one can truly answer your question without knowing what the motors are connected to and the application.


for example.
a motor not connected to anything pulls 10 amps.
connect that motor to a car seat track for example and the motor will pull 13 amps.
when that motor hits the end of travel, it will pull 20 amps.
when it starts to run from the end of travel, it pulls 15 amps.
add a 200 lb person on the seat and it will require more power.


just an example and things to consider.
james