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windmill
Thu 07 January 2010, 15:59
Hello Gents,

In my application, I do have a couple of appliances (servos, breakout board, spindle controllers) require different current under the same 24V DC power, they are:
1): Servo drive: 24VDC with 12A
2): Control signals: 24VDC with 4A
3): Control signals for the spindle controller: 24V with 40mA

I am trying to just use on power supply to supply all the power supply since they are all 24V DC. So I made an electrical drawing diagram with circuit breakers, but I am not sure if it is correct. Please help me to verify the diagram. Thanks,

jhiggins7
Thu 07 January 2010, 16:33
Windmil,

I don't know exactly what you are asking.

If you have 3 "loads" (servos, breakout board, spindle controllers) which each require 24 volt power, you simply wire each load to the 24 volt power supply. Each load will "draw" the amount of current (amps) it needs to operate. You simply have to calculate the size of the power supply to meet the "draw" of all the loads...as you have done. You should always size the power supply to be, say, 25% greater than the calculated load.

One note, you include the breakout board in the list of loads requiring 24 volts. If you are using the PMDX-122 BOB, it only requires 12 volts DC or 9 volts AC. 24 Volts would probably destroy the PMDX-122 BOB...I haven't tried it and I definitely would not recommend it.

In my case, I built a dual voltage power supply which delivers 12 Volts DC and 24 Volts DC. I use 12 Volts DC to drive the BOB and I use 24 Volts DC to drive 24 Volt coil Contactors for the Spindle, Dust Collector and Vacuum Hold-down. I also use 24 Volts for the E-Stop Circuit.

Perhaps you could expand your diagram and provide some part specifications or part numbers.

windmill
Thu 07 January 2010, 18:09
jhiggins7,

Thank you for your quick reply. Here is the mean well power supply that I will choose, http://www.meanwell.com/search/se-450/default.htm

I am not really an electrician, so I would prefer buying parts off-the shelf. By the way, I am using a servo motor (Teknic Servo Motor M-2311P-LN-16K with encoder/ coupler) to drive the gantry machine. The motor's cont. current is 5A, peak is 15A. I do have 3 axis, so I figure out the current that I need is:

3*5*0.67=10.05A, So I picked that 12A meanwell power supply.

I don't know if the calculation is correct for the Teknic brushless servo motor (since this equation is for steppers, right?)

Another question that I have is the circuit breaker. Right now, I choose the circuit breaker according the the cont. current from the motor, but not from the peak current, am I right?

Thanks,

Windmill

Gerald D
Thu 07 January 2010, 20:03
Windmill, are you building a MechMate?

windmill
Fri 08 January 2010, 02:38
Greald,

Not exactly, I am trying to build a desktop 3 axis gantry machine using servo motors.

Gerald D
Fri 08 January 2010, 03:21
Sorry, "This forum is exclusively for MechMate builders or people seriously interested in building them." <----- quote from front page.