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Top Indramat DDS Drive Failures and Fault Codes

Testing an Indramat Drive Repair - DDS

Finding Fault:  Initial testing of Indramat DDS drive during repair.

There are 3 common failures related to the Indramat DDS series drives.  They are #60, #61, and when a unit shows nothing on its display.  We will take a look at these, the causes and the possible cures.  There are many other faults, and we will show a list of those as well.  The Indramat DDS drives are very robust units, but will need refurbishment from time to time.  It is rare to have one that cannot be rebuilt.

Allen Bradley 1391 AC Controller

Allen Bradley 1391 Drive Fault Code Break Down – What They Mean, Causes, How to Fix

The 1391 Series Allen Bradley drives are still in use on many machines throughout industries, especially automotive, aerospace, food production, wood products and conveyor-type systems.  A stout servo drive system, the 1391 comes in both analog and digital.  Here, we will look at the analog side, but it’s meanings are the same in digital.

Indramat power supply DIAX04

Recent Job Report #5 – Indramat HVR Power Supply Repair- DIAX04 Series

Today, we have an Indramat HVR02.2-W010N power supply in for repair. After a static check, we connect power to the unit to confirm the fault. It is then disassembled; and taken to our wash-down area for a full cleaning and bake, before we begin the repair. This unit came from a parts manufacturer in Detroit and experienced a voltage spike which burned up incoming line voltage. 

Indramat HDS drive repair at Repair Zone

Top 5 Error Codes for Indramat Diax04 – HDS Drives: Descriptions and Solutions

Error codes are flashed when there is an issue with your Indramat HDS (Diaxo4) drive.  Error codes are usually 4 digit codes beginning with an E or F.  The following are the most common error codes seen on a faulty Indramat HDS drive, found on Eco-Drives as well:

Indramat HDS drive error codes and repair

Indramat HDS drive system will flash an error code when not working correctly.

#1  Code F208/UL

Description: If a servo motor or a different drive has been changed out for the original unit in the loop, due to troubleshooting or an upgrade.

Solution: This is fairly simple.  After powering up and code is registered, hitting reset on the drive and power supply, then cycle power and unit should be functional.  

Frequently checking backup batteries on HMI's is essential preventative maintenance protocol.

2 Things You Need to Do When Buying or Repairing an HMI (Human Machine Interface)

HMI repair

Maintaining an up-to-date copy of the software in your HMI can save your machine.


A Common Scenario When Purchasing a Machine: a conversation with a service technician from the field

Let me go over some of the common problems when purchasing a used machine. Yesterday, I was basically at a customers, they bought a machine, when they purchased the machine they thought it was in good, working condition, at least that’s what they were told.  

How Aging Components Impact Your Servo Amplifier or Drive

Aging of electronic components like resistors, capacitors, and diodes can fault out your drive, bringing your process to a screeching halt.

Aging of electronic components like resistors, capacitors, and diodes can fault out your drive, bringing your process to a screeching halt.

Most Common Reasons for Failure

Industrial electronics such as servo drives, power supplies, amplifiers, HMI displays and any electronic equipment that has printed circuit boards (PCB’s or PWB’s), will potentially fail during their life-time of usage.  No matter how well it can be designed, there are numerous reasons a circuit or components on a PCB will fail.  Some of the most common reasons are over current, over voltage, contamination, corrosion, manufacturing defect, operating environment and aging.  In this article, we will look at aging, and how it affects the electronic boards and components on your unit.

Start-up procedure for Fanuc Alpha servo amplifiers.

Start-Up Procedure for Fanuc Servo Amplifier (Alpha Series) – Overview

Here is a quick guide overview to start your Fanuc Alpha servo amplifier after it has been replaced, removed, or repaired in your machine.  This is an excerpt from the official Fanuc maintenance manual.  For all Alpha Series Control Motor Amplifiers (servo amplifier units  A06B-6089-H*** and  A06B-6090-H***).

(NOTE: When maintaining or inspecting the servo amplifiers, keep the power supply switched off. Also, make sure that the “CHARGING” LED (red) beside the circuit breaker on the front panel of the servo amplifier is off as well.)

Quick Guide for Fanuc System Troubleshooting: Is it the Cable, the Amplifier, or the Servo Motor?

Checking a Fanuc system to find out why it is faulting.

Finding fault with a Fanuc servo system

When your CNC machine outfitted with Fanuc system stops working, the person running it or maintenance personal must quickly figure out the root-cause and then formulate a plan to get the machine running again.  Seems simple, but rarely is it simple or easy.

Being a Fanuc repair facility, a common happening is that we will get a Fanuc motor or amplifier in for service, then go through our process to evaluate and we find out: the unit runs fine

Your Options For Failed Allen Bradley Equipment: Repair, New, or Surplus


When your Allen Bradley equipment fails you have options.  You can choose to purchase the Allen Bradley equipment new from the Original Equipment Manufacturer (OEM), have the equipment repaired, or buy surplus.

There are many advantages to having your Allen Bradley equipment repaired versus buying new from the OEM, or purchasing surplus inventory.

Purchasing from OEM:

  • Many Allen Bradley series have been deemed obsolete and the OEM may no longer support your series
  • High expense
  • May need to replace entire system which can be costly
  • Long lead times can lead to lengthy downtime for your machine

10 Signs Your Servo Equipment Needs Repair

Fanuc Servo Motor needing repairIs your servo equipment noisier or less efficient than when you first purchased the equipment? Your servo equipment is probably ready for a thorough inspection, cleanse, repair, and simulated machine test.

The following list, discusses ten noticeable signs your servo equipment is ready for a repair, which can help save you from unexpected machinery downtime.

1. Noisy Servo Equipment

If your servo equipment is louder than usual, do not ignore the sound. When your servo components become noisier, the noise can mean the bearings have worn out, the keyway has worn out, the shaft is not fitting right, and/or the fans are not working correctly.

Most Common Alarm Codes for Fanuc Servo Amplifiers (Indicated on the Status Display)

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Most common alarm codes found by Repair Zone technicians during repair.

When your CNC machine suddenly stops working what is the first thing that you do?  Probably open the cabinet and check the controller or amplifier?   If your machine is equipped with Fanuc Automation components, you probably check the status display on your Fanuc servo amplifier and see a number displayed?

These numbers are called alarm codes, or error codes.  There could be 9 possibilities.  The drive and amplifier technicians at Repair Zone use these alarm codes, also called fault codes, to help them troubleshoot during a repair.  When

Drive Cabinet Air Condition fan contamination due to lack of filters. Cooling fan failures followed by drive failure due to overheat condition.

2 Reasons Why Your CNC Machine Will Break Down

By Jade York with Jonathan VanDenboom

The very nature of a CNC machine suggests an environment that can be harmful to itself and cause its own demise: Lots of lubricants and cutting fluids, oil, metal shavings, dirt and dust, etc. are everywhere.  Sound extreme?  Well, it is, and a recent visit to a manufacturing facility confirmed a long known fact: If not properly maintained, CNC and other machinery will fail sooner than later.

Job Report #3- Fanuc Spindle Power Supply

contaminated power supply

We received a Fanuc Spindle Power Supply Module for repair.  From the looks of it, this power supply seems un-repairable and should be thrown away due to the vast amount of contamination and debris.  It has been denigrated by its hostile environment; the cause can be as simple as a lack of maintenance and cleaning.  In some machines, however, cleaning is not possible.

The pictorial below follows Adam, a Fanuc repair specialist at Repair Zone, on his way through this sticky repair.  See if he can save this power supply, and the customer!

Recent Job Report #2- ALLEN BRADLEY 1391 AC Servo Controller Repair


Last week, we received in an Allen Bradley 1391B-AA45 AC servo controller for repair.  We have repaired hundreds of these units and have a high rate of success.  This customer, in the automotive industry, said they needed it back in a week, if that was possible.  We had it back to them in 3 days.  We cleaned and baked unit, replaced fan and several components at the board level and more.  If you need a repair of your servo drive or other automation equipment, please call 1(888) 706-5263 for immediate service.  To browse our inventory, go to www.repairzone.com  Enjoy!

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Very contaminated Allen Bradley servo controller.   Technician Adam H. removes logic board

                                                                                   during disassemble.

pic4-cropped   pic5-cropped

Test Equipment-Techniques for finding bad components on Printed Circuit Boards (PCB)


Adding diagnostics equipment to enhance your test capabilities is an important part of any electronic repair environment. There are many techniques that can be used to find bad components on a Printed circuit boards (PCB), from a servo drive, or controller. Some of the more common testing equipment are: Multimeters, Huntrons, and capacitors. 


A multimeter, multitester, or a VOM (Volt-Ohm meter), is an electronic measuring instrument which combines several measurement functions into one unit. It is used for basic fault finding and field service work, or to measure at a very high degree of accuracy. They can be used to troubleshoot electrical problems in a wide array of industrial and household devices such as electronic equipment, motor controls, domestic appliances, power supplies, and wiring systems.

4Digital multimeters (DMM, DVOM) display the measured value in numerals, which eliminates parallax errors, and may display a bar of a length proportional to the quantity being measured. Modern multimeters are often digital due to their accuracy, durability and extra features. In a digital multimeter the signal under test is converted to a voltage and an amplifier with electronically controlled gain preconditions the signal.

DMMs are able to offer as standard the basic measurements that would typically include:

  • Current (DC) -(Typically low current without an amp probe)
  • Current (AC)-(Typically low current without an amp probe)
  • Voltage (DC)
  • Voltage (AC)
  • Resistance

Proven Cost Savings


Here at Repair Zone we aim high to satisfy our customers. When you purchase a product or service through Repair Zone our goal is to exceed your expectations.

Repairs allow our customers to hold on to existing equipment longer, thus stretching their initial investment even further as opposed to re-tooling their machines. For example, a 10 to 15 year-old Allen Bradley 1391 Series drive shows superior up-time versus a newer model. Replacing with new can be postponed until well into the future. With the particular model in this example, the newer drive has required far more repairs than the older drive, and the older drive may show a steady or even decreasing frequency of failure with a  decrease in maintenance costs.

We are very price-conscious while pricing each product or service we offer. We want to ensure our customers are receiving our products and services for the best price possible. We compare past  prices to calculate an

Why Do We Clean Drives? What Are The Benefits?

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Many environments are not ideal for precision servo electronics and automation components. Industries such as: Automotive, wood working, plastic plants, water treatment or water associated facilities, and many more, contain small particles of grease, oil, dust, moisture, and all other particulates in the air and surrounding areas. These particles are contaminates and will find their way into your drive.

Most cooling systems are broad systems within the drives. A  fan(s) will be blowing the hot air off of the driver circuits and boards in a broad fashion. As the fans blow, the contaminants are blown across all the critical areas of the drive.

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Repair Zone- Competitive Analysis

contaminates on drives

The Repair Zone team was curious of the quality of services provided by other companies compared to the quality we provide here at Repair Zone. We recently sent out a Fanuc Amplifier for repair to one of our top competitors. Included with the  return of our Fanuc Amplifier was a detailed repair work report.

They Listed:

  • 19 capacitors replaced
  • unit cleaned
  • fuse replaced
  • integrated circuit

Repair Zone Specialists reviewed and checked the equipment and found:

50-plus Years of Drive-system Evolution

Allen Bradley Drives

As part of its 60th anniversary celebration, Process and Control Engineering (PACE) offers this look back — and ahead — at the continuous search by production-line engineers for smooth operation and speed control. PACE editors spoke with design engineers from numerous markets, who shared their perspectives on how drives have evolved in terms of usability, increased functionality, and improved reliability. Companies represented on the distinguished panel of experts include WorleyParsons Limited, JDN Monocrane and Fisher & Paykel. Among the highlighted technology developments is the use of variable-speed drives in master-follower arrangements; use of drives in hoisting zero-speed lock-rotor applications; and the Smart Drive clothes washer. Read the full article at  http://www.pacetoday.com.au/features/motors-and-drives-control-and-efficiency-shape-the.

Servo Drives & Controllers Defined

Find your servo drive and controller today

What is the difference between a servo controller & a drive?

Controllers and drives are two separate servo system components. With many different original servo equipment manufacturers, you can easily decipher a drive from a controller, such as with Fanuc and Indramat drives and controllers. However, Allen Bradley is an exception when defining controllers and drives, because Allen Bradley has named their servo component, which is equivalent to a drive, an AC servo controller.

What is a controller?

A controller takes signals from different machine monitoring devices (e.g. tachometers, linear scalesencoders, proximity switches, etc.), and the controller figures out mathematically where and how the servo motor needs to move.  The monitoring devices providing are both external to the servo equipment, and some of the devices are part of the servo equipment pieces, such as servo motors have encoders and resolvers built into them and spindle motors have encoders and speed sensors.

The majority of controllers are used for programming offsets, diagnosing, machine status, and part counts.

What is a drive?

In general, a drive takes a signal from a controller; the signal from the controller tells the drive what to compensate for in respect to the servo and/or spindle motor to achieve programming.

A drive can also tell a motor’s status by letting you know if the motor is overheating or if it is being overworked.

Allen Bradley: The exception 

Though drives and controllers can be technically defined, Allen Bradley has been using the terminology AC servo controller for their servo components that are reminiscent of servo drives. An example of an Allen Bradley servo component equivalent to a drive is the Allen Bradley 1391 series of AC servo controllers. The 1391 series AC servo controllers are actually drives despite the name, because the Allen Bradley 1391 AC servo controllers control the servo or spindle motors’ movements.

Allen Bradley does make servo equipment called drives now, such as the PowerFlex series drives. The fairly new PowerFlex series drives, however, are still dissimilar to a regular servo drive. Allen Bradley PowerFlex drives are variable frequency drives (VFDs), which the VFDs do not require a controller, because the controller is built into the drive.

Other Manufacturers

Manufacturers such as Fanuc and Indramat have the traditional separate servo drive and servo controller system. A couple well known series for Fanuc drives and controllers are the Alpha series and the C series; for each type of series, there is both a drive and a controller, which work together in a servo system. A well-known series of Indramat servo drives and controllers are the Diaxo series drives and controllers, which also work together in a complete servo system; the common Indramat Diaxo controllers are the BTV controllers.

Though, there is a clear difference between servo drives and servo controllers for most original equipment manufacturers, Allen Bradley has set its own standards for what makes up a servo drive and servo controller and how they work. Allen Bradley is the exception when defining servo controllers and servo drives.

Industrial Monitor Types: What is the difference?

CRT, HMI, Operator Interface, Industrial Computers

CRT, HMI, Operator Interface, and Indusrtial Computer Explained

Many terms exist for seemingly similar pieces of servo system equipment: Operator interface, HMI, CRT Monitor, Industrial Computer. So, what do the different terms mean, and which servo component terms have similar or different meanings?

Operator Interface

Operator interface refers to a control system a person uses to communicate with the multiple linked servo system components. Operator interfaces include both hardware and software allowing a person to interact with the machinery. Operator interfaces are manufacturer specific, which requires you to use the same manufacturer for all servo equipment parts.


HMI stands for Human Machine Interface. Like an operator interface, an HMI is made up of both software and hardware and allows a user to communicate with the machinery; however, HMIs are part of one machine or a piece of equipment, whereas operator interfaces are part of linked servo equipment. The user communicating with the machinery can manipulate the machines system and view the effects of the users’ manipulations. The HMI is manufacturer specific to the machinery and servo system you are using.

CRT Monitor

Cathode Ray Tube (CRT) monitors are used to display faults, positioning, and machine status. Some CRT monitors do work as Operator Interfaces; for example, Fanuc’s CRT monitors are made to both display and allow a person to communicate with their machinery. Cathode Ray Tube refers to the glass tube screen of the monitor; today CRT monitors are outdated and inefficient compared to LCD monitors; however, CRT monitors can easily be updated to LCD monitors through LCD retrofitting. CRT monitors are manufacturer specific to the servo system and machinery you are using.

Industrial Computer

An industrial computer is a programming terminal; it is used to program the machinery. The industrial computer can be used to change the settings to pick up different faults, and it can be used to save programming for different machinery. Industrial computers are a necessity for older machinery, which rely on the industrial computer for programming. The positive aspect with industrial computers is the computers are not manufacturer specific, so if your machinery still requires an industrial computer you are able to replace it with any other industrial computer if necessary.
Industrial computers are not used in newer machinery systems, because new machines’ servo components have programming specific parts built into the equipment, such as drives, which makes the industrial computer obsolete in newer machinery.

Can You Run a Servo Motor with a Variable Frequency Drive?

Servo System

Testing Servo Motors and Drives

Can you run a servo motor with a Variable Frequency Drive? First, lets look at how a servo amplifier works with a servo motor.

A servo amplifier actually fires DC voltage into the three phases of a servo motor. Each time a phase is fired, it is completely dependent upon rotor positioning reference to the stator windings to be fired. In other words, you need commutation to run a servo motor. Most servo motors will have an encoder that is coupled to the rotor and aligned to give rotor positioning reference to stator windings.

We have actually ran a Yaskawa servo motor open-loop on a variable frequency drive (VFD) The results were not good. You see, no matter how we tuned the drive, the end result was a very inefficient motor that drew high amps and had no torque.  So the answer is:  yes, but not very well.

Top 5 Strategies to Keep Your Machinery Up and Running

Servo System Equipment

Find out how to keep your servo equipment up and running!

(1) Keep it Clean!!!

The most important strategy to keep your servo motors and industrial electronics running is keeping your servo motors and industrial electronics clean.

The filters, fans and heatsinks are the areas that require the most cleaning, because the filters, fans, and heatsinks are the most common fail points in your automation equipment due to the areas becoming clogged with oil mist and dust.

The heatsink, which its purpose is to draw heat away from the servo automation equipment, can cause overheating if it becomes clogged. When the automation equipment overheats, this can cause stress on the component and machinery, and eventually, the IGBT will blow up.

Allen Bradley 1391 Series – AC Servo Controller – A Legend Lives On!

1391 Drive

Allen Bradley 1391 AC Controller

The Allen Bradley 1391 series was first introduced in 1992 and is still widely used today.  Noted for its stout build and workhorse mentality, the 1391 series has machine owners holding on to them much longer than most legacy servo-automation equipment made by other companies.  And though they are obsolete, parts are still available and companies are supporting them through repair, exchange, and selling reman units.

The 1391 drives come in 2 versions,

in 2 versions, Series A and Series B.  Though they are functionally equivalent, the Series A logic boards cannot be used in Series B Controller.  But, the Series B logic board can be used in a Series A Controller.

The 1391 contains many of the standard features required in a servo system:

  • An easily removable Logic Board for easy inspection, troubleshooting, and diagnostics.
  • Transient voltage protected input.
  • A circuit breaker that opens all 3 AC leads in the event of a short circuit situation.
  • A 300V DC power bus supply with a shunt regulator.
  • A shunt regulator resistor to minimize energy generated by the motor during braking.
  • Velocity loop components that compensate or inertia.
  • A power line/DB contactor.
  • (3) Controller ratings.
  • UL listed.

The Allen Bradley 1391 also contains these user selectable options:

  • Torque or Current Amplifier Operation
  • Contactor Auxiliary Switch
  • External Shunt Regulator Resistor

The 1391 series includes these Catalog numbers (models):

TheThe following is what the nameplate nomenclature stands for on an Allen Bradley 1391:

The 1391 Series drives are used with the 1326ab servo motor series from Allen Bradley.  The power supply is contained inside the unit, so there is no need for a separate one.  These units run for a long time and in harsh conditions, and when they do break down, they can be repaired and put back in a machine and run with further longevity.  It is also rare that one of these 1391 drives is damaged beyond economical repair.  The legend lives on!


Allen Bradley 1336 Drives

1336 Servo Drive

Allen Bradley 1336 Drive

The Allen Bradley 1336 Plus was the jumping off point for the later 1336 Variable Frequency Drives (VFDs); the 1336 Plus drive line was introduced in 1994, and became the most installed VFD base in North America. The entire 1336 Plus line went obsolete on December 31, 2010. The 1336 Plus II was an upgrade from the 1336 Plus, which the 1336 Plus can be converted to the Plus II.

1336 Series Similarities & Differences

Allen Bradley 1336 variable frequency drives (VFD), including the 1336 Classic, 1336 Impact (E), 1336 Force (T), 1336 Plus (S), and 1336 Plus II (F), are built upon a similar base, and each drive has the same basic start/stop control interfaces and communication options.  The similarities of the different Allen Bradley 1336 VFDs are a major advantage when repairing the drives; once the repair technician learns how to repair one model in the 1336 drive line, the repair technicians are able to repair any 1336 VFD.

The main differences between the 1336 VFD models are the drive’s power output and the drive’s dimensions, which depend on the specifications of each model. The different 1336 VFDs’ power output and dimensions vary to fit the specifications of a given machinery application.

What is the 1336 Regen?

One area of confusion when looking into the different 1336 VFDs is the 1336 Regen (R). The 1336 Regen (R) is not a VFD; however, if you are not familiar with the different 1336 series and models, you may not realize what exactly the 1336 Regen (R) is.

The 1336 Regen (R) works with the all of the Allen Bradley 1336 VFDs. The Regen converts the three-phase AC input source to a DC output source, and it acts as a brake output where the line regeneration package limits the amount of inrush current and provides AC voltage and magnitude information to the converter.

1336 Series Today

Today, the Allen Bradley 1336 lines are obsolete, including the 1336 Regen (R), with the last line (1336 Force) becoming obsolete in October 2012; however, most of the 1336 VFD drives can easily and affordably be converted and upgraded to versions of a PowerFlex drive, which PowerFlex drives are the most up-to-date Allen Bradley drives.

To learn more about RepairZone’s Allen Bradley Repair Capabilities, click the button below:

Allen Bradley Repair


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What Can Cause a Following Error?

Following errors are common cause

Repair Zone Drive Technician

Repair Zone technicians get many people calling about ‘following errors’ and assume it is a problem with their drive and asking what causes them to occur.  Most of the time it is due to 2 things:

  1. the feedback device and the positioning information it receives
  2. or the cable transmitting the information

They are mainly caused by the controller, not the drive, and the information being fed to them by their feedback device or the cable.

We’ve Come A Long Way with Variable Frequency Drives: Cost and Quality

Variable Frequency Drives

Variable Frequency Drives

As with anything, there is an old saying, “You get what you pay for.”  In many cases, variable frequency drives (VFD’s) have come down in price, but then again, it all depends on the application.  For instance, using the 7.5 HP theory,

I would not use a drive that does not have the option to run in closed loop sensor vector mode for an extruder.