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I've got 4 lots of servo drivers and 4 lots of 2.2KW motors to match.
9.5AMP each. Think peak amp is 19AMP each
The servo driver is single phase or 3-phase 220V input and it outputs to the motor single phase or 3 phase 220V. Now obviusly in UK there is no single phase 220V.
My building as 100AMP main fuse.
I've spend a fortune on this servo&motors.
I know the running cost will be high on single phase but will it run on single phase.?
If the drives are rated for 220V single phase input, then no problem.
just realisred a 10kw shower even draws 40amp so aslong as nothing else is used "for testing purposed" should be fine.
Can I ask what it means by peak amps. i take it that is when it is under heavy load?
Yes, ''peak amps'' is under absolute maximum load. A very unusual condition in a properly sized system. For the most part, the servos will use a small fraction of their rated power except for brief bursts of acceleration as needed.
So when all 4 motors are running and aslong as they are under the main fuse 100AMP (UK household) I should be fine. I seeQuote:
Originally Posted by Jim Dawson
Although the outlets will not work as they are rated 13amp.
It just means running a new 80-100amp three core cable from the main fuse board to the garage.
Yes, I think you will need to run a heavy cable to your garage.
Out of curiosity what kind of machine are you running? 2.2kW is unusually large for axis motors on most machines one would find in a home shop.
powering actuators for a motion simulator. 4 motors; weight of 200kg been tossed about. load will vary between all 4.
will use a clamp around cable amp reader to study the amp usage
If it is around average of 40 amps running those then i'll be dead happy
So the advantages of three phase motors is : cheaper to run i guess. loads is spread over the three phases.
and nothing else.
but then again 3 phase motors are more expensive to buy in first place.
i wonder if the effiency/savings are around 25-30%
Ahh, a very cool project. I would love to see some pictures if you would like to share.
Just to put the expected power usage in perspective, Below is a graph of my shop power usage over the last hour. The only machine running is my CNC lathe. Three 1.8kW axis servos, and a 7.5kW spindle servo. The shop power is 240V single phase, and the lathe is fed through a rotary phase converter to supply 3 phase power to the machine.
The short spikes are rapid moves, moving a 750KG carriage. The spindle is pretty lightly loaded for the current part, about 15% max power. The two excursions above 5kW are when the air compressor kicked on. I would expect to see something like this for your power usage.
https://www.cnczone.com/forums/attac...d=470548&stc=1
25 amps max , is that all?
why did it shoot up at those points?; blockages. jams?
why do the servo manufactures put these sort of high figures when they sell them?
is it because incase of a jam? i bet when it locks or jams the ampage goes so high; so realistically you dont need such a high TRIP.
You can put a lower trip to always be on the safe side. INCREASE the longevitiy of the servo and motor *thumbs up"
you can always replace the trips with higher rating if required in future.
Yes, about 25 amps max. The shop is fed with a 100 amp breaker off of my house main.Quote:
Originally Posted by damunk
The two points > 5kW is the air compressor added to the load. The other short spikes is just the power required to make rapid moves (about 400 IPM) of the carriage. It takes a lot of power to accelerate a 750Kg carriage to 400 IPM and stop it again over about 6 inches. The torque required to do that is in the 25Nm range
The servos are rated by 4 parameters, Max continuous power, Absolute Maximum power, torque, and RPM (rated and max). You can always limit the torque in the parameter setup, and thus the max power usage. Most times there is a setting for max amps also, so you can set the overload fault trip point.Quote:
why do the servo manufactures put these sort of high figures when they sell them?
is it because incase of a jam? i bet when it locks or jams the ampage goes so high; so realistically you dont need such a high TRIP.
I would use breakers or fuses rated per the manufacturer recommendation, and just set the trip parameters in the drive to what you desire.Quote:
You can put a lower trip to always be on the safe side. INCREASE the longevitiy of the servo and motor *thumbs up"
Well The fact that I will be using a new cable on it's own to power it means thats the only thing that can go wrong /fire up although it shouldnt like you said just use the correct breakers.
When I get to that stage will just get an electrician anyway.
I appreciate this chat because like you said , gotta feelings your setup is similar to mine. yours is more weight but I wiill have more acceleration and travel. hope to see simiar results then will be happy dayz.
Well the good news is that servo motors only use just enough power to do the task at hand. They draw very little power when idle. So average power is normally a very small fraction of rated power. If my machine were to get into a condition where all of the servos needed maximum power at the same time, it would most likely trip the main breaker. But that condition is a very unlikely possibility, for all practical purposes really can't happen.
I think you will be fine with your setup.