LaserPhysics Reliant 300WC help

[FRITZ HID]

Hi Everyone!

I scored a LP Reliant 300WC this weekend. condition unknown, but it looked clean. after cleaning some FOD out of the fan cowling, i fired it up, 3x in total. over the period of a day, fired all 3 times perfectly. adj control worked fine. beam rose and fell accordingly. no odd smells or anything...

then after it got dark, i went to fire it up a 4th time... fan-check, filament coil humming-check, 1st relay click-check, then the igniter... 5 full cycles... no beam.
tried 2x after 30 min rest...
nadda...
after removing the cover i discovered 4 diodes (Rect) that 2 were charred, the other 2 showed thermal stresses and all had warped solder joints...

these are the diodes & their location in the chassis...






has anyone else had this specific issue, if so, was there another cause i should be looking for or just replace them and hope that does the trick?

 

[paul1598419]

I'm not familiar with this particular device, but from my years of experience I'd say they are four rectifiers made to be a bridge. The three legged device next to it may very well be a regulator IC or transistor. They could have burnt because a diode in the bridge shorted, or there could be a short immediately at the output of the bridge. It should have been fused, but I can't tell from your photos if it was. If it isn't, I'd certainly add that to this circuit.

Edit: I see there is a part number on the regulator and it would be easy to find out exactly what it is. It is an inexpensive regulator IC that can carry up to 3A. Your Reliant 300WC is an Argon laser that outputs 300mW and this is the driver board for it. I'd say that it is probably limited to the immediate power supply, but that isn't certain. I think Bloomplye has an old thread on the tear down of this board.

 

[DJZ]

Your Reliant 300WC is an Argon laser that outputs 300mW and this is the driver board for it.

Actually, the 300WC is an Argon/Krypton producing several blue lines, a couple green lines, 1 or 2 yellow and 1 or 2 red lines. Sweet little unit!

Hopefully it's just a burned up diode but I would certainly test for shorts. I'd make sure the diodes are failed before replacing them.

I opened up my Reliant 1000M and I appear to have an identical power supply board so if you need any meter readings or component id's I may be able to help.

 

[paul1598419]

I'd replace all the diodes in that bridge and also check for shorts. You will also want to cut/ clean the carbon off the PCB where the diodes burned and charred the board.

 

[icecruncher]

:drool::drool:

AFAIK those are almost impossible to find for any price in the realms of normal people.

Post some pics if you get if running.

I'd love a 300WC !!!!!!!!

Hi Everyone!

I scored a LP Reliant 300WC this weekend. condition unknown, but it looked clean. after cleaning some FOD out of the fan cowling, i fired it up, 3x in total. over the period of a day, fired all 3 times perfectly. adj control worked fine. beam rose and fell accordingly. no odd smells or anything...

then after it got dark, i went to fire it up a 4th time... fan-check, filament coil humming-check, 1st relay click-check, then the igniter... 5 full cycles... no beam.
tried 2x after 30 min rest...
nadda...
after removing the cover i discovered 4 diodes (Rect) that 2 were charred, the other 2 showed thermal stresses and all had warped solder joints...

these are the diodes & their location in the chassis...






has anyone else had this specific issue, if so, was there another cause i should be looking for or just replace them and hope that does the trick?

 

[FRITZ HID]

:drool::drool:

AFAIK those are almost impossible to find for any price in the realms of normal people.

Post some pics if you get if running.

I'd love a 300WC !!!!!!!!

you don't wanna know what i paid for it. lol

 

[paul1598419]

In that case, I hope you are successful at repairing the driver board.

 

[ultimatekaiser]

In that case, I hope you are successful at repairing the driver board.

lol good luck! These are definitely nice lasers! I love my 643 omni though, and wouldn't give it up except for maybe a SP-2060.

you don't wanna know what i paid for it. lol

Bet its got nothing on my D3's pricetag...

 

[icecruncher]

you don't wanna know what i paid for it. lol

Right place at right time, I'm sure

I just need that to happen to me with one.

 

[FRITZ HID]

$30. i saved it from an electronics recycling place that i like to frequent. i also picked a very nice SP-107b 35mW HeNe from there.
the LP ar/kr had already been picked at by someone, they yanked the Hr meter out of it :/ but the rest of it was in good shape. a lil FOD in the fan cowl but the tube and boards are as clean as can be.
when i 1st fired it up, the beam seemed to be well within specs. very bright and the reds came in at about 1/2 power. i'm just hoping that these 4 diodes getting replaced will be all it needs to get back to functioning.
i'm thinking of replacing the fan with one that i can exhaust outside, being in FL, we have enough heat indoors as it is, i don't need a 2kw blast furnace making my A/C work even harder than it does.
can these be over cooled? as in, i have several high CFM fans but they are over the specs of the stock fan,... if i use one of these, will the higher CFM cause problems with over-cooling?

 

[ultimatekaiser]

Very nice! I wish I found deals like that more often...and it is best that it's left as designed usually. Too much or too little cooling can cause odd things to happen and uneven cooling. A somewhat faster fan might not hurt if the circuit can handle it... But realistically some tubes don't mind, others get touchy. It's hard to say... But too big a thermal gradient can damage the tube. The tube is designed to operate within a certain temperature range... You actually wanted to get a little bit hot because that's actually what drives the ionization And cavity length.... But too hot or too cold and you'll potentially end up warping or popping it or losing power.

 

[hakzaw1]

great thread guys- super info + 8 when I can..good luck!!

 

[FRITZ HID]

Very nice! I wish I found deals like that more often...and it is best that it's left as designed usually. Too much or too little cooling can cause odd things to happen and uneven cooling. A somewhat faster fan might not hurt if the circuit can handle it... But realistically some tubes don't mind, others get touchy. It's hard to say... But too big a thermal gradient can damage the tube. The tube is designed to operate within a certain temperature range... You actually wanted to get a little bit hot because that's actually what drives the ionization And cavity length.... But too hot or too cold and you'll potentially end up warping or popping it or losing power.

well, i was thinking a ducted fan, 120v self powered, not off the laser PSU... i Could connect a relay to have it controlled by the laser but that seems unnecessary IMO. maybe just an indicator light to let me know when it wants the fan on/off and just flip the switch by hand. there doesn't seem to be any feedback signal to the main board so not worried about that aspect. just want to be able to vent the heat outdoors and if at all possible, quiet things down some. stock fan is loud as hell, lol.
guess i look into a slightly larger CFM fan, prob squirrel cage, and manually operate it. laser powers fan 1st then everything else, then lets fan run about 90s or so after shut down, maybe less so i think i can handle that issue.

new diodes will be here in a few days (3 at most) and i'll swap them out and check other components,......
then i'll say the Gas Laser Prayer and attempt firing.

Send good thoughts everyone! :angel:

 

[VirtueViolater]

May the laser gods be with you
Danny

 

[paul1598419]

Really, don't forget to clean up that burnt board too. You don't want another current path in that circuit.

 

[FRITZ HID]

Really, don't forget to clean up that burnt board too. You don't want another current path in that circuit.

ohhh don't worry... spent the last 20 years repairing electronics. have a full rework station in my lab. but TY!