Title: NEJE E80 weak laser power after fire – stable 24V, normal current draw, new protective lens
Hello,
I need help diagnosing a NEJE E80 laser module.
I purchased the NEJE Max 3 / E80 laser from the seller/store, and before the problem it was working very well. The E80 module was able to cut thick pine wood and had strong cutting performance.
During one cutting job, the material caught fire. After this incident, the cooling fans were damaged and I replaced them. The module still powers on, the laser still emits, and the beam can be focused, but the cutting power is now much weaker than before.
I have already checked the following:
Power supply voltage:
24.1V idle
around 23.7–23.8V under 100% laser load
so the power supply does not seem to collapse.
GRBL settings:
$30=1000
$31=0
$32=1
LightBurn / firmware:
the laser temperature is displayed normally.
Example message: “Laser temperature: 22.7C”
During engraving I have seen around 42C maximum, so the temperature feedback appears to work.
Current measurement in series on the 24V input:
Laser OFF / idle: 0.62A
10% power: 0.90A
30% power: 1.47A
50% power: 2.12A
75% power: 2.90A
100% power: 3.79A
This means the current increases normally with PWM power, and at 100% the module draws about 3.79A from 24V. Because of this, I am not sure if the main driver board is the problem.
I also replaced the protective lens with a new one. The focus distance is correct, around 24 mm. The nozzle was also removed for testing, so I do not think the beam is hitting the nozzle.
The laser still creates a focused spot/line, but the optical cutting power is much lower than before. For example, even at very slow speed and 100% power it barely cuts compared to how it worked before the fire.
My questions are:
Based on these measurements, is this more likely to be:
degraded laser diodes after overheating/fire;
damaged or contaminated internal optics;
damaged coating on the internal lens/FAC optics;
driver board problem;
cooling / NTC / fan related problem?
If the E80 still draws normal current at 100% but the optical output is weak, does that usually indicate degraded LDs or internal optical loss?
Is there any safe way to inspect the internal optics of the E80 without losing alignment?
Are the internal LD / optical assembly parts available as spare parts, or only the full E80 module?
Can someone confirm what should be checked first after a fire event where the fans were damaged but the module still works electrically?
I can provide photos/videos of:
the module;
the protective lens;
the test lines;
the current measurements;
the inside of the module if needed.
Any technical guidance from NEJE support or users who have repaired an E80 module would be greatly appreciated.
One possibility is that during the fire, excessive heat built up because the cooling system failed to dissipate heat quickly enough. This can cause irreversible thermal damage to the laser diodes (LDs).
If you’ve confirmed that the input voltage and power are normal, then thermal degradation of the LDs is the most likely cause.
Please note that new NEJE mainboards with updated firmware now feature enhanced thermal protection. The system communicates directly with LightBurn—if the module overheats due to oil contamination, poor heat dissipation, or other factors, the firmware will trigger an automatic pause to prevent further damage.
Yes, I have confirmed the input voltage and current. The power supply remains stable at around 23.7–23.8V under 100% load, and the module draws about 3.79A at 100%. The laser still emits and focuses, but the cutting power is much weaker than before the fire.
Based on your explanation, it seems that the LDs may have suffered irreversible thermal degradation.
Could you please advise what the recommended repair solution is in this case?
Is it possible to replace only the E80 LD/optical assembly, or is the only practical solution to replace the complete E80 module?
Also, if I buy a new E80 module, can you confirm that the currently sold version includes the updated mainboard/firmware with enhanced thermal protection and LightBurn communication?
Actually I am looking for solution to repair them but…
The E80 features real-time temperature feedback—a standard in all NEJE laser modules. The recent updates primarily involve the motion control board firmware. You can simply open the NEJE software and upgrade to the latest version to access these improvements. For more details on how the LightBurn thermal linkage works, please refer to the NEJE Blog section, which has a dedicated explanation.
Regarding the repair, the only viable solution is to replace the entire optical system module. The LD optical assembly is incredibly complex; it involves the LD array and a sophisticated 4XFAC multi-lens system. Aligning these components requires highly specialized laboratory conditions and precision tools. Furthermore, the LDs are filled with protective inert gas during sealing. Repairing this is virtually impossible for individuals, as any breach of the seal compromises the gas protection and leads to immediate failure.
From an economic standpoint, even at the factory level, repairing a single module is not feasible. The labor and calibration costs involved would significantly exceed the cost of manufacturing a brand-new module. Therefore, replacement is the only practical and cost-effective recommendation we can provide.
Thank you very much for the detailed explanation and for clarifying the situation.
I understand that the E80 optical system is a very complex sealed module, with the LD array and 4XFAC multi-lens system, and that repairing or realigning it is not practical outside factory/laboratory conditions.
Based on your explanation and my measurements, it seems likely that the module suffered irreversible thermal degradation during the fire incident.
Could you please advise me what the best practical next step would be in this situation?
I would like to ask whether there is any possible replacement option for the complete E80 optical system module, or if the only realistic solution is to replace the full E80 laser module.
I would appreciate any guidance you can provide, including whether there is any service option, replacement part, or recommended way to proceed.
The majority of the E80 core module’s cost comes from its 4-FAC multi-lens system, which accounts for most of the manufacturing expense. Therefore, we do not currently offer the optical assembly as a standalone replacement part for users. Typically, we recommend replacing the entire module.
However, if you are a developer requiring this for R&D purposes, we can provide support for the optical module upon request.