Tag Archives: fanuc


A06B-6079-H106 Servo Amplifier by FANUC – Product Spotlight

The A06B-6079-H106 is a 1-axis Alpha Servo Amplifier Module that uses a Type A or Type B interface. When installing the module, observe the ambient temperature and output rating requirements. The continuous output rating  or continuous operation period of some amplifiers may fall as ambient temperature increases. If the amplifier is used continuously with an excessive load applied, the amplifier may be damaged. Before operating the amplifier for the first time, mount and adjust the speed and position detectors so that an appropriate waveform is obtained. If this is not done, the motor may not rotate normally or the spindle may fail to stop as desired.

If the motor makes any abnormal noise or vibration during operation, stop operation immediately. If operation is continued, the A06B-6079-H106 could become damaged. Take corrective action before continuing with operation. Be sure to only replace the battery when the servo amplifier is on. If the battery is replaced while the power is turned off, the stored positioning data will be lost. Also ensure that the battery connector is correctly inserted. The cover on the front of the A06B-6079-H106 carries a label indicating the specification code. When mounting a previously removed front cover, take care to mount the correct cover to the right unit.

You can observe an instantaneous motor current value on the A06B-6079-H106 by checking the voltage across a reference voltage check pin and a motor current check pin with an oscilloscope. You cannot use a device such as a multimeter to find the correct values. To check the power supply voltage, use the reference voltage check pin and the power check pin with a multimeter, oscilloscope, or similar. This will tell you the power supply voltage for the control circuit in the amplifier.

MRO Electric and Supply has new and refurbished A06B-6079-H106 Servo Amplifiers available now. For more information or to request a quote call us at 800-691-8511 or email us at sales@mroelectric.com.


FANUC A06B-6079-H206 – Beyond the User Manual

The FANUC A06B-6079-H206 is a 2-axis servo amplifier module. Its standard dimensions are 380 x 60 x 307 mm. The Status display is a 7-segment LED that indicates the operation status on the module. If the Status display is not on then the power is not turned on, the cable has a power connection, or the module is defective. If the module is defective, replace the fuse or servo amplifier. If there is a single middle line on the display, the control power supply is waiting for the ready signal. If all the outside lines are on, the servo amplifier is ready to operate and the servo motor is supplied with power. If an alarm is issued on the servo amplifier, a value other than “0” and “-” is displayed.

A pin board can be used with the A06B-6079-H206. The use of a check pin board allows you to observe the signals inside the servo amplifier. CN1 and CN2 are wired with a one to one correspondence. The connector pin numbers correspond to the check pin numbers. You can observe an instantaneous motor current value by observing the voltage across a reference voltage check pin and a motor current check pin with an oscilloscope. Note that you cannot use a device as a multimeter to observe the correct values. You can also measure the voltage across a reference voltage (0V) check pin and a power check pin with a multimeter, oscilloscope, or the like to observe the power supply voltage fr the control circuit inside the servo amplifier. If the measured voltage is within 5% relative to the nominal voltage, the measured voltage is considered acceptable.

A special lithium battery can be installed in the A06B-6079-H206. Be sure to install the battery with correct polarity, otherwise it may overheat, blow out, or catch fire. Use the factory-installed protection sockets in the unused connector after installing. This can help prevent the battery from short-circuiting.

MRO Electric and Supply Company sells new and refurbished A06B-6079-H206 servo amplifier modules.  To request a quote or for more information, please email sales@mroelectric.com or call 800-691-8511. 



Troubleshooting a Fanuc Motor

Here are some basic principles for troubleshooting a FANUC motor circuits with meter or megohm meter. This procedure will show you how to test for shorts in windings, cables, or opens. Before starting to test, make sure to turn all all the power sources to the machine and then disconnect the 3-phase motor lines from the drive end. Visually confirm that there are no problems with the cable and then begin testing.

Testing for a short to ground:

  • Using an Ohm meter: Disconnect all power from machine. Check all three wires at T1, T2, and T3 (all three phases) to the ground wire. The readings for this should be infinite, and if it is zero or reads any continuity then there is a problem with the motor or the cable. For this disconnect the cable and check each separately. Be sure to make sure leads on both ends are not touching anything, including the other leads. Most servo motor shorts can be ready with a regular quality  meter going to at least 10 megaohms.
  • Using a Megohm meter: Disconnect all power from machine. Check all three wires at T1, T2, and T3 (all three phases) to the ground wire. Reading should be between 600-2000 Megohms. Most shorts will be below 20 Megohms. Be careful not to touch the leads or the wires to anything when taking the reading because it can give a false reading. There should be about 1000 Ohms of resistance for each volt of incoming power, but this is not a standard rule. If it is 230meg to 600meg there may be deterioration in the cable.

Testing for Open or Short in the windings:

  • Using an Ohm meter: Disconnect all power from the machine. Put meter on ohms and test T1 to T2, T2 to T3, and T1 to T3. The range should be between 0.3 and 2.0 ohms, with most being at about 0.8 ohms. If it is zero there is a short between the two phases. If it is an open the reading will be infinite or well above 2,000 ohms.
  • Cable and plug notes: Often times the connector on the cable to the motor will get coolant in it. You can dry it out an retest, if it is still bad the inserts will get burn marks in them and cause a slight short, so they need to be replaced. If it is a DC motor, check the brushes. There should be 3-4 round caps to remove around the motor. Under these there is a spring with a square block (brush). Check to see how much is left, they may need to be replaced.


MRO Electric has a large stock of FANUC motors available. If you would like a replacement or spare, or if you have any questions, please call 800-691-8511 or email sales@mroelectric.com.
FANUC Motors
FANUC Motors

Fanuc AC Spindle Motor Repair

We recently rebuilt a Fanuc AC Spindle Motor, part number A06B-0828-B302. The customer was in a rush and needed this 357 lb motor so that he could get back up and running right away. We didn’t have the motor in stock, but we did have all of the parts in stock to build the motor.

Within 3 days we were able to rebuild, repaint, and fully test the motor to get it ready to go back out via freight to the customer, so they were back up and running in less than a week.

Our rebuilds for these size motors usually take 2-3 days, so we were right on schedule for this Fanuc motor. We have the full list of motors that we stock and repair here, and you can email sales@mroelectric.com for more info. We also have pictures of the finished product below as an example.

A06B-0828-B302 Fanuc AC Spindle Motor
A06B-0828-B302 Fanuc AC Spindle Motor
A06B-0828-B302 Fanuc AC Spindle Motor 2
A06B-0828-B302 Fanuc AC Spindle Motor 2

Fanuc Motor Safety Procedures and Tips

We have people ask about best practices for working with Fanuc motors all the time, so here are some Fanuc Motor Safety Procedures and Tips. For more info you can visit our website here or email sales@mroelectric.com.
When working with servo motors:
•NEVER pick up or carry the motor by the cables or the shaft. (Always carry by the frame.) Use a crane or lift tomove the motor when necessary.
•NEVER drop or subject the motor to impact. The servo motor is a precision device.
•NEVER set heavy or sharp objects on the motor or cables. Do not step or sit on the motor or cables.
•NEVER use a metal hammer on any part of the motor. If it is absolutely necessary to use a hammer, use a plastic hammer.
Keep the motor properly secured and away from the edge of the work area when servicing the motor, as a dropped motor could

cause personal injury or destroy the motor

Basic Motor Safety, Procedures, and Best Practices
• Be safely dressed when handling a motor.
Wear safety shoes and gloves. Avoid loose clothing which can get caught
on the motor. Be careful not to let hair get caught in the rotary section of the motor. Do not handle the motor with wet hands.
• Shut off the power before working on a motor. Wait at least 5 minutes after the motor is shut off before touching any
power terminals.
• Always use the correct cables. Centroid cables are shown in the motor compatibility table. Wiring diagrams and pin outs
for motors are provided in Appendix B.
• Ensure that the motor and motor related components are mounted securely. Ensure that the base or frame to which the
motor is mounted to is strong enough.
• Do not touch the rotary section of the motor when it is running unless instructed to.
• When attaching a component having inertia to the motor, ensure any imbalance between the motor and component is minimized.
• Be sure to attach a key to a motor with a keyed shaft.
• Use the motor in appropriate environmental conditions. Do not store flammables in close proximity to the motor. When
not in use, store the motor in a dry location between 0° to 40° C.
• Do not remove the nameplate from a motor

Fanuc A06B-6089-H105 Servo Amplifier – Product Info

The Fanuc Servo Amplifier A06B-6089-H105 is an SVU α series control motor amplifier unit. It can be used within systems with one or two feed axes. This amplifier has an integrated power supply to accommodate smaller systems. The A06B-6089-H105 servo amplifier is in compliance with VDE 0160, UL, and CSA safety standards. For more information please visit our product page here.

Continue reading Fanuc A06B-6089-H105 Servo Amplifier – Product Info

Replacing Fanuc C Series Servo Amplifiers with α Series Servo Amplifiers

C series and SVUC comparisonIf you experience a system failure due to a Fanuc C series servo amplifier, (A06B-6066-H002, H003 etc.) you may feel like your only option is to replace it with the same exact unit. However Fanuc also offers the α series servo amplifiers which features improvements over the C series. In most cases you can replace your C series servo amplifier with the α series servo amplifier that has the identical final four numbers of the C series model number. The chart below outlines this:

C series comparison pageThe advantages of replacing your C series amplifier with an α series amplifier are:

  • A built in power supply
  • A second interface, type B, as well as the more conventional type A interface
  • Updated power device, intelligent power module, to reduce power loss and increasing reliability

α series amplifiers are also designed with the same dimensions as the C series so that you can install them into your current system easier.

To check out our selection of C series and α series amplifiers check out our website!


A06B-6117-H205 Fanuc Amp – Product Video

Below is a product video for an A06B-6117-H205 Fanuc Amp unit that we have in stock and ready to ship out the same day the order is placed. This servo amp has been fully tested and the specs for it are below along with the manual number.

Rated Input: 283-339V, 5kW
Maximum Output Voltage: 240V~
Rated Output Current:
L axis: 6.5A
M axis: 6.5A
N axis
Manual No.: B-65282
Standard: EN50178

This amplifier unit is a direct replacement for the A06B-6114-H205 Fanuc amp and can be substituted in for the 6114 version with no setup changes to your current machine.

Fanuc A06B-0075-B503 Motor Product Video

Here is a video of one of the many Fanuc AC motors that we have in stock,  and this one is the Fanuc A06B-0075-B503 Motor. This is an AC Fanuc motor that has a brake and a keyway already installed. At 22.85lbs and 8.1 X 15.3 X 6.5 inches, this is one of the smaller motors that Fanuc manufactures. The motor in the video is brand new and comes in the original factory packaging, we only took it out of the packaging to get a video of it. If you are looking to get your old motor repaired, we do also offer a repair service for these AC motors with a standard turnaround of 3-5 days.

If you’re also trying to figure out if your motor is bad you can check out this other blog post that we put up to show some basic steps for testing your motor. The page is here, it has some useful steps to go through to confirm that your motor is causing your problem.

If you have any questions or need additional information feel free to email us at sales@mroelectric.com.

Product Video – Fanuc A06B-6066-H008 Servo Amp

To highlight some of the products that we have in stock and service we’ve decided to start uploading videos of the individual products. Here is a look at the Fanuc A06B-6066-H008 Servo Amp that we have in stock. The unit has been recently refurbished, is fully tested and is ready to ship out today if need be. We also offer repair on these servo amplifier units with a standard turnaround of 3-5 days.