|
Posted by Ignoramus23517 on June 5, 2009, 4:53 pm
Please log in for more thread options
I have several 3 hp DC fanuc servos, which I want to test for basic
operation. Any idea what I can quickly do to spin them up. One
connector is four big pins, another is many small pins. I assume that
big pins are for DC current plus field voltage?
i
|
|
Posted by jw on June 5, 2009, 5:02 pm
Please log in for more thread options On Jun 5, 3:53=A0pm, Ignoramus23517 <ignoramus23...@NOSPAM.
23517.invalid> wrote:
> I have several 3 hp DC fanuc servos, which I want to test for basic
> operation. Any idea what I can quickly do to spin them up. One
> connector is four big pins, another is many small pins. I assume that
> big pins are for DC current plus field voltage?
>
> i
I don't know about 4 big pins. Should just be +/- pins for power.
The set of small pins would be the encoder (or resolver) for feedback.
In any case, apply power to the main power pins and it should spin. A
good first test would be to ohm out the windings. "Normal" will be
3-4 ohms. If you have a set, it will give you a population study for
normal.
Do you have an asking price in mind?
JW
|
|
Posted by Karl Townsend on June 5, 2009, 5:34 pm
Please log in for more thread options
>I have several 3 hp DC fanuc servos, which I want to test for basic
> operation. Any idea what I can quickly do to spin them up. One
> connector is four big pins, another is many small pins. I assume that
> big pins are for DC current plus field voltage?
A DC servo is just a DC motor with a feedback device. Resolver and tach for
old ones, encoder for new ones. Check motor operation by hooking large wires
to a 12 volt battery.
Many fanuc servos are AC brushless units, quite a different animal. I don't
know of a way to test them without connecting to a servo drive.
karl
|
|
Posted by Ignoramus23517 on June 6, 2009, 12:29 am
Please log in for more thread options Thanks, guys, I posted a followup in a separate thread about actual
testing.
i
>
>>I have several 3 hp DC fanuc servos, which I want to test for basic
>> operation. Any idea what I can quickly do to spin them up. One
>> connector is four big pins, another is many small pins. I assume that
>> big pins are for DC current plus field voltage?
>
> A DC servo is just a DC motor with a feedback device. Resolver and tach for
> old ones, encoder for new ones. Check motor operation by hooking large wires
> to a 12 volt battery.
>
> Many fanuc servos are AC brushless units, quite a different animal. I don't
> know of a way to test them without connecting to a servo drive.
>
> karl
>
>
|
|
Posted by Ned Simmons on June 5, 2009, 5:56 pm
Please log in for more thread options On Fri, 05 Jun 2009 15:53:22 -0500, Ignoramus23517
>I have several 3 hp DC fanuc servos, which I want to test for basic
>operation. Any idea what I can quickly do to spin them up. One
>connector is four big pins, another is many small pins. I assume that
>big pins are for DC current plus field voltage?
They're almost certainly brushless motors, which are essentially
3-phase permanent magnet synchronous motors. The "many small pins" are
the connections for the commutation feedback, which is most often 3
Hall effect sensors that tells the drive the angular position of the
rotor. If there are more than 10 pins or so, there may be encoder
connections mixed in there as well.
You can drive a brushless motor with a VFD (without the commutation
feedback), but getting the VFD's parameters set properly is not
trivial.
If the resistance of the motor's 3 phases is equal, and it generates
an equal voltage on all 3 phases when you spin it, the motor itself is
probably OK. I'm not sure what you could with limited equipment to
test for other potential problems like a failure in the Hall sensors,
insulation breakdown, or a demagnetized condition.
--
Ned Simmons
|
| Similar Threads | Posted | | Followup -- How do you test a DC servo motor | June 6, 2009, 12:27 am |
| Mitsubishi HA80 CS Servo Motor- Which drive to use | August 26, 2009, 6:59 am |
| Motomatic II servo driver | May 10, 2006, 8:31 pm |
| Mori Seiki SL1 Servo error | May 23, 2006, 2:51 pm |
| Re: WTH Servo Dynamics amp repairman, or WTB rebuilt SD amp | May 30, 2006, 4:11 pm |
| Need Haas 5C Rotary Servo Controller Manual | November 23, 2008, 4:32 am |
| Haas servo bar & irregular push length's ? New too Barfeeding | July 19, 2008, 5:20 am |
| Motor Alarm ? | May 11, 2006, 4:03 pm |
| fanuc motor specs | May 10, 2006, 10:44 am |
| Doerr AC motor, need information | March 8, 2008, 11:54 am |
|
|
Yahoo! 
Google 
Windows Live 
del.icio.us 
digg 
Netscape 
XML Sitemap
> operation. Any idea what I can quickly do to spin them up. One
> connector is four big pins, another is many small pins. I assume that
> big pins are for DC current plus field voltage?
>
> i