What Is the 5136 Alarm?
Simply put, alarm 5136 represents DC Link Undervoltage. In Fanuc αi, βi series servo drive, when the DC bus voltage is lower than the minimum threshold, the system will trigger this alarm.
To put it bluntly: it means that the driver "can't eat enough electricity”, and as a result, it can't drive the motor normally.
What Are the Common Causes?
We have summarized several types of high-frequency causes, each of which has been encountered.
1. Power supply problems
Once, the machine tools of an automobile parts factory frequently reported 5136. After checking, we found that the voltage in their factory often fluctuates, and the voltage drops a lot during peak hours. In other words, the quality of the power supply is not stable, leading directly to the drive "lack of power.
2. Loose or oxidized wiring
This kind of problem is very hidden. A customer sent the driver, the appearance of the problem, but the power always alarm. We dismantled a look, DC bus terminals have oxidation, contact resistance increases, the voltage with a load will fall.
3. Drive internal components aging
Especially capacitors, generally 5-7 years life. Once the capacity decreases, the DC voltage can not support the load. We have tested a number of old drivers, capacitance has been significantly reduced.
4. Motor overload or short-circuit
Some customers have spindle or servo motor faults, such as short-circuit or excessive load, instantly pulling down the voltage, which can also trigger the 5136.
5. Environmental factors
High temperature, dusty workshop and poor heat dissipation will also make the driver more prone to alarm.
How Do We Troubleshoot?
Usually, we will follow the steps below to locate the problem.
1. Measure the power supply first
Use a voltmeter or power quality analyzer to see if the input voltage meets Fanuc requirements (±10%). Often times, this is where the problem lies.
2. Check the wiring
Remove the DC Link terminals and look for signs of looseness or oxidation. Clean and retighten as necessary.
3. Measure the bus voltage
Taking 200V class driver as an example, the normal bus voltage should be 300-325VDC. If it is obviously low, it is most likely a problem with the capacitor or power module.
4. Drive test
Here is Songwei's advantage. We have Fanuc special test bench, can simulate the real working conditions, the drive unit, spindle module, power module run together, to avoid "single point test” missed the problem. 5. check the motor with megohmmeter.
5. Check the motor
Measure the insulation with a megohmmeter to see if there is any short-circuit or aging of the windings; also check if there is any mechanical stall or overload.
Repair or Replace?
This is the most important issue for customers. We generally suggest this:
* Repair what can be repaired: For example, if the capacitor, IGBT and other common components are damaged, the repair cost is only 40-60% of the cost of buying new parts.
* Serious damage or old models: If the power module burns out, has repeated problems, or the model is outdated, it is more suitable for direct replacement or refurbished parts.
Practical experience shows that about 65% of Fanuc drive problems can be solved by repair.
How to Prevent?
We always emphasize that prevention is more important than repair. A few practical practices:
* Regularly replace capacitors: Check them once every 5-7 years, don't wait until something goes wrong.
* Stabilize the power supply: Adding a UPS or voltage regulator, if possible, can prevent 30-40% of failures.
* Pay attention to the environment: Keep the cabinet clean and good heat dissipation.
Why Choose Songwei?
We have extensive experience in Fanuc drive repair and testing:
*
Specialized test benches: Support a complete set of intermodulation of drives, spindle modules and power supply modules, avoiding misjudgment caused by separate testing.
* Strict standards: In accordance with European safety and quality requirements for testing, the results are more reliable.
* Flexible program: Whether you buy brand new, refurbished, or repaired, we can provide the right choice.
Our goal is simple: to help our customers reduce downtime, extend equipment life and ensure production stability.
Summary
Fanuc Servo Alarm 5136 is essentially the result of insufficient voltage. It can originate from a power supply, wiring, internal components of the drive, motor, or environmental issues. With proper troubleshooting and professional testing, the problem can be found and resolved in most cases.
If you are currently experiencing a 5136 problem, please contact
Songwei and we can help you quickly locate the problem, fix the drive, and get your production back to normal based on your site conditions.
