Laser Machine Service near Pinxton, on an Omtech 740 x 400 – 60watt – Central Coffins Ltd
The visit to our new customer Central Coffins Limited was because they had an issue with their Omtech laser machine. The customer had reported that the unit would not power on correctly and the HMI would just flash on then off. This repair and laser service was conducted by our highly experienced service engineer ‘Gavin Edwards’. The service visit included: –
Omtech 749 x 400
Upon arrival at the Central Coffins Limited premises the Omtech machine was visually inspected. The machine was found to be very dusty.
The machine was powered on to observe the fault reported by the customer. The following videos demonstrates what was observed.
To fault find this particular problem, there is a need to follow the flow of the electrical connections. First off the incoming voltage was checked and was found to be stable. The output voltage was measured and the 24V output from the PSU was fluctuating between 0V and 10V. The 24V PSU was replaced with a new unit, but the issue persisted. This step is to show whether it is the PSU that is faulty, or something further down the line.
On the 24V output of this PSU there were 3 connections. The connections were all disconnected and the machine turned back on. The voltage was then again measured. The PSU was now outputting a normal voltage. The three wires were then reconnected one after the other to find which wire was causing the issue. The offending wire was identified and traced to the controller. From previous experience this type of fault is the result of some wiring being fault and pulling the 24V down to ground. In essence the live and neutral wires are shorting.
The 24V rail on the controller was removed and the machine tested. The error had again disappeared. So each 24V output was traced. The resulting fault finding indicated that there was an issue with the auto-focus system. Further discussions with the customer whilst on site indicated that the customer had previously had an issue with the workbed only moving downwards. This shows a fault with the auto-focus pen. Omtech had already supplied a replacement auto focus pen and cable, which aligns to the fault finding indications.
The old auto-focus pen was removed and the customers own auto-focus pen was installed. Upon inspection of the old cable, you could see strands of the copper wire poking through the insulation, which would have caused the short.
Whilst discussing with the customer above any other errors that have occurred on the machine the customer did mention that they had previously had a ‘Water Protect’ error on the controller which prevented the laser from firing. They had managed to bypass the issue at the time but were unsure as to how. Upon investigation it was found that the water protect function had been disabled within the software. This is, however, a critical safety feature as disabling it would allow the laser to operate potentially without any cooling being active, potentially resulting in severe damage to the laser tube.
We would only advise to use this disabling feature in extreme circumstances, such as processing jobs whilst waiting for either replacement parts of a service engineer to visit.
The ‘Water Protect’ function was re-enabled and the laser was attempted to fire. It correctly displayed the ‘Water Protect’ error. The system was then checked for the cause. The flow sensor was investigated and was found to be faulty, this was replaced. Whilst installing this new unit, it was also noted that the chiller unit had been connected with the water flow going in the wrong direction. This was correct accordingly.
Following all of the above the unit was turned on and was now operating correctly. The engineer then preceded with following on with some standard service checks and maintenance.
- Inspect and Clean all Mirrors
- Focusing Lens Inspected and cleaned – was found to be installed upside down
- Cleaned Nozzle and Laser Head Carriage
- Water Cooling Chiller Inspection, Clean, Drain & Refill – Cleaned chillers filters
- Inspect and Clean all Belts
- Inspect, Clean and Lubricate all Linear/Guide Rails
- Electronics Inspection
- Check overall machine function by Test Cutting Customer Materials
When it came to the extraction of the fumes the customer had a unique setup. The customer was advised that this setup was inadequate and if they didn’t want to install a dedicated extraction unit, then at least an inline centrifugal extraction fan and extend the pipe to outside the building.
Any of the consumable items mentioned above, Lens, Mirrors, Laser tubes, Power supplies are all available and can be bought separately in our online shop.
If you would like further information on our Laser Machine Service near Pinxton capabilities or anywhere else in the country, or any other Laser Repairing requirement or Laser Application, please request a call back or, talk to one of our service engineering specialists by going to our contact page – link below.
Contact Us for Laser Engraving, Marking & Cutting Advice (thinklaser.com)
Frequently Asked Questions:
How do I improve Inconsistent Cutting Depth?
Verify that the laser head is correctly focused for the material’s thickness
Check for debris or dust on the mirrors and lenses.
Ensure that the cutting bed is level across the entire work area.
How do I stop the laser from cutting unevenly?
Inspect and clean the optical components (mirrors and lenses).
Check that the work bed is level; an uneven bed will affect cutting depth.
Ensure the material is flat and secured in place on the bed.
How to stop the laser head dragging on Material
Ensure that the material is flat and not bowed or warped.
Check the height adjustment of the laser head and set the correct z-axis distance.
Verify that the workpiece is secured properly on the bed.
