Laser will not turn on

[Robert Zielke]

I have a 50W blue 300x500 Chinese Laser. I had an accident while trying to use the laser at a very low setting about 15%. The laser was about 4 inches lower on the bed the the program called for. I stopped the program. I then tried to track the same program. The machine went to the highest speed and crashed into the front of the machine. Then at high speed crashed into the right side of the machine before I could hit the emergency stop. I turned off the machine. I then restarted it. It started normally. This time when I ran the same program it tracked normally in the correct position. I tried to rerun the program and every seemed normal but the laser did not start. I looked at the laser tube in back and I do not see any damage. Any ideas on how to test the electronics and/or the laser tube?

Robert Zielke

[Gene Uselman]

Welcome Robert- be sure to save your Vendor and User files as they are hard to recover.

Restarting any electrical device is the first item on the first aid list- that seems to have fixed most of your problems- good job. It is unlikely the tube is damaged, to troubleshoot you should find your High Voltage Power Supply, usually there is a LED on it when voltage is supplied to the tube. You may need a mirror to see the area the wiring is affixed to the PS. If it is not firing it is either the PS or the wiring leading into it. This PS has high voltage coming out of it- BE CAREFUL. Check the LED and get back to us. Gene

If you are familiar with wiring diagrams I can supply a general schematic.

[Robert Zielke]

The PS LED green light is on. I do not understand about the wire not being connected. I will look. There is a test button on the PS but I do not know what it does.

If I need to replace the Power Supply would it be a good idea to get a higher rated one so I can upgrade the tube in the future. I do not know if a 50 W laser tube needs a particular set of requirements that is different with the various laser tube wattage (60 W or Higher).

Robert Zielke

[Gene Uselman]

The green light indicates power to the PS, the test button will fire the tube. Again, dangerous voltage, be very careful and have a plan in mind before proceeding. You should probably have another person to observe the tube, the test button will likely supply full power. A larger PS will work fine if you intend to upgrade your power tube. I did not mean a wire is disconnected- merely pointing out where to look for the led light. Be cautious!

[Robert Zielke]

I am aware that voltage to the laser voltage can be above 20,000 Volts.

I tried the test button and the laser did not activate.

Does this mean the PS needs to be replaced? I was thinking about eventually upgrading the laser tube so I was thinking about the 70 to 90 W range. I have the original tube and it is three years old and I have had no problems until yesterday. I generally use low power in the 15 to 25% range.

I mostly engrave wood and acrylic but sometimes cut wood such as walnut and purpleheart. Purpleheart has a very high resin content and smokes heavily. I vent the laser to outside so I am not worried about the exhaust.

Do you recommend a company that makes the Power Supply? Will a PS that supports a 70 W laser support a 50 W laser.

If I get a new tube it will probably be Reci.

Robert Zielke

[Dave Vigness]

Uh, here's a quick thought, is your water protect switch functioning properly. Memory says connect WP to ground to bypass, but double check me. With everything good, if you don't have a WP connection, you will get no power to the tube. You may be one of the lucky ones that it failed open. I had one that failed closed and it was an inline that also cut my flow by half when it failed. Nearly cooked a tube.

[Gene Uselman]

Dave, as usual, has a good point. A larger PS can be used on your current tube with no problems. If there is a brand name on the PS, they will normally have a troubleshooting guide online. If you are a Amazon devotee, they sell Cloudray PSs and I beleive they are generally reliable. With the proviso that all parts dealer sell parts from many different companies and some of their Quality Control is poor if any. I have had good luck with LightObject and they seem to stand behind their product. Marco is the main man and is very knowledgeable.

Your next step should be finding a manual on your PS and working out the Water Protection possibility. Troubleshooting electrical problems boils down to checking all systems upstream from the PS and eliminating each in turn. I was trained on this stuff in 1965-6-7 and still retain about 5% of what I learned.
Or- simply replacing parts until something works.

[Robert Zielke]

I have no idea where the water protection switch is located. I do not know where the WP signal line connects to the PS.

The only lines labeled on the PS are the two AC lines and the ground line for the top connector. There is a fourth line above that on the connector but is not labeled. Would that be the WP connection to the PS?

There are five lines on the bottom connector but they have no labeling.

I know that there probably is no standard for the wiring. The wires are red, red, black, blue, and green on the lower connector from top to bottom.

There is no information or label on the power supply included with the machine.

Failing open means that there would be no signal at the PS. is that correct?

I looked at other power supply pictures and the lower connector were labeled H, L, P, G, IN and 5V.

I assumed G was ground and 5V was the 5 Volt line but have no idea what the other letters mean. Can you tell me what they are?

Just in case it is the PS, I ordered a PS that looks identical to the one that is in the machine with the same connectors and test button.

[Gene Uselman]

H and L are probably high and low- does it run on 110V or 220V? It should be labeled. One of my machines was built as 220V and the other is 115V to the wall and then had a huge transformer to change to 220V which actually runs the machine. The Chicoms are 220v [as well as most of the civilized world]. If you have a Chiller the water protect probably comes from that- sometimes there is a water protect switch [which is what Dave is talking about.] The WP can be hooked to the controller, or PS or heaven knows. Good luck to ya sonny. I will be here all weekend if you have further questions. Gene

[Robert Zielke]

My power supply has a switch on the top side that is set 115 V.

I have found some jpg file with the pin outs labeled. The problem is they use different pin outs.

The first one is as follows: G, P, L, G, IN and 5V.

The second one is as follows: H, L, P, G, IN, and 5V

The third one is as follows: K+, K-, G, IN, 5V

My connector has 6 pins and the last one is not attached to a wire. Since all pin outs have 5V as the last pin I believe it is not connected.