Acorn DMM Power requrement sanity check

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RaptorMachine
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Acorn DMM Power requrement sanity check

Post by RaptorMachine »

Hey guys,

i want to be safe but not overkill. currently ordering breakers e stop contactor etc and just want to make sure i order the correct parts..

system background Bridgeport BOSS
2 hp spindle motor using a FMX TD 400 3 HP VFD with a 10.5A output ( will be running 220 single phase input )
3 DMM Dyn4 750 watt servos ( will be running at 220 volts )

so i believe i need 3 20 amp dual pole breakers for the servos and a 15 amp double pole breaker for the spindle

and a 75 amp contactor ? is this over kill ? what do you think the system would really draw as i need to run a breaker and outlet from the electric box as well

just want to be sure i order the correct parts

thanks ! Joe
RaptorMachine
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Re: Acorn DMM Power requrement sanity check

Post by RaptorMachine »

one last thing.. maybe someone can recommend a nice terminal block for the main power.. thanks !
RaptorMachine
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Re: Acorn DMM Power requrement sanity check

Post by RaptorMachine »

looking a little closer at the DMM videos, do i need a contactor per DYN4 ? and they are showing a 20 amp circuit breaker followed by a 12 amp contactor.. so power ----- circuit breaker ------ contactor -------- DYN4

thanks in advanced

Joe
Last edited by RaptorMachine on Wed Feb 10, 2021 8:41 pm, edited 1 time in total.
tblough
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Re: Acorn DMM Power requrement sanity check

Post by tblough »

I would say the servo breakers are properly sized to prevent damage to the motors and drives, but you will NEVER see a combined load of 60 amps from them. A 30A main disconnect (or 45A) with a 30A main breaker should be more than enough for that system.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
RaptorMachine
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Re: Acorn DMM Power requrement sanity check

Post by RaptorMachine »

tblough wrote: Wed Feb 10, 2021 8:32 pm I would say the servo breakers are properly sized to prevent damage to the motors and drives, but you will NEVER see a combined load of 60 amps from them. A 30A main disconnect (or 45A) with a 30A main breaker should be more than enough for that system.
thanks for the reply Tom,

so a 30 amp main to a 30 amp contactor to 3 20 amp breakers for the individual servo drives ? or run separate contactors for each servo drive ?

joe
tblough
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Re: Acorn DMM Power requrement sanity check

Post by tblough »

I'd probably run a single contactor since you'd never want to control just a single drive.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
martyscncgarage
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Re: Acorn DMM Power requrement sanity check

Post by martyscncgarage »

Yes, one estop contactor for 3 750W servos is fine.
I believe individual breakers are overkill. That's your call. Did you take a look at the FADAL TRM project I did?
I used a line reactor and per DMM's suggestion, I used a regenerative resistor on the non-counterbalanced Z axis to cure a drive fault problem when the Z axis was coming down. Between the two, made me a believer in using them.


Marty
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