At Precision Zone, we specialize in Fanuc product repairs which include a wide range of AC Servo drives. One of the many servo lines we service is the Fanuc analog servo line.

These drives originated back in the mid-1980s but can still be found running today! The model number for these units begins with A06B-6050 and come in 1, 2 and 3 axis varieties. These velocity control amplifiers run off of 185VAC from a corresponding Fanuc power transformer unit. The power transformer has a similar model number beginning with A06B-6050 but then is designated by H021, H022 or H023. Various jumper settings on the drive allow for setting alarm detection levels, loop gains, and pulse coder feedback settings, among other things.

The ease of access to check terminals on the main PCBs allow for voltage checks for troubleshooting and preventative maintenance.

When assessing the functionality of a drive, our repair team conducts a four-step evaluation:

• 1. Visual Overview
• 2. Static Test
• 3. Checks Under Power
• 4. Alarm Codes Verification

This overview is Precision Zone’s basic troubleshooting process. Once our repair team starts on the job, we use specialized and customized testing fixtures, Huntron trackers, signal generators, oscilloscopes, milli and mega ohm meters, as well as any other necessary tools we have available to assure quality repair work. Most importantly, every repair is fully tested in our custom-built simulators under load with a motor to replicate real-life working environment.

Precision Zone goes as far as using heating chambers and overnight dynamic testing, when applicable, to guarantee performance of the repaired product when it arrives back with the customer.

Repair Process for Fanuc Alpha Series AC Analog Servo Drives

Visual Overview

When conducting a visual check, the technician inspects the drive for any mechanical damage to the drive itself and any printed circuit boards. The technician then proceeds to verify connections are tight and correct inside the drive and there are no loose screws, wires or debris. Additionally, the unit is checked for any burn marks on the components, printed circuit boards or chassis. During the visual inspection, excessive dirt on cooling components is noted as well as the functionality of the heat sink.

Basic Static Check

Output Module Testing

To perform output testing on these Fanuc AC Servo Drives, Precision Zone repair technicians use digital multimeters with diode testing capabilities and also take resistance measurements to conduct a static test. For these units, in particular, our team of technicians uses the diode function of the multimeter as well as huntron devices to check the output modules.

The capacitor values on the PCBs are verified and any relays, contactors or circuit breakers in the drive are examined to ensure proper functionality.

Checks Under Power and Alarm Code Verification

Upon successfully passing all visual and static checks, the drive is tested under power. Any reported alarm codes are verified and if no alarms are present or once the drive has been fully repaired, the drive is tested in our Fanuc simulator. Alarms can be verified by an array of LEDs directly on the servo pack.

List of Alarms

S SERIES

For more information on these alarms as well as any other failures, please give us a call at 800-551-4420 or email us today!

Precision Zone Repair Benefits for Fanuc Alpha AC Analog Servo Series

• 1. FREE evaluation by expert technician includes:
• Visual Inspection
• Static Check
• Power Tests
• 2. FREE job estimate
• 3. 12 month warranty on our parts and labor
• 4. Flat Price
• 5. Exchange Option
• 6. Rush Service