New Sanwu 304 green laser not working (solved)

[LeroyLaserkins]

I already contacted Sanwu lasers. I bought all three of the 304 lasers (violet red green) all of them work except for the green one, they all have saftey lock with key. I’ve tried everything switching out different batteries etc. opened them all today green one never turned on once

 

[Philipnzw]

Try using the tail cap from one of the other 304 lasers. It could be a tailcap issue. I had similar problems with a 303 green laser.

If it is a tailcap issue then you could just ask sanwu to send you a replacement tailcap.

 

[LeroyLaserkins]

Try using the tail cap from one of the other 304 lasers. It could be a tailcap issue. I had similar problems with a 303 green laser.

If it is a tailcap issue then you could just ask sanwu to send you a replacement tailcap.

I tried using tail caps from the other 303s and it didn’t help

 

[Philipnzw]

Ah, then it's probably other issues/a dead laser.
Since you already contacted sanwu, that wouldn't be a problem. Sorry to hear that your laser is DOA but those 303,304 style lasers aren't exactly high quality. But it's a good thing that you purchased it through a reputable source such as sanwu.

 

[Giannis_TDM]

I tried using tail caps from the other 303s and it didn’t help

switch around the battery polarity, In the green laser the battery - should be facing the head and the + the tail cup

 

[LeroyLaserkins]

switch around the battery polarity, In the green laser the battery - should be facing the head and the + the tail cup

Problem solved!

 

[Encap]

Problem solved!

You are lucky that the 304s Sanwu resells are from one of the best manufacturers of those low cost mass produced lasers and have reverse polarity protection. Most of those 300 series types don't and all you need to do to kill one is put the batteries in the wrong way once and the laser is toast/killed.

 

[Alex2893]

You are lucky that the 304s Sanwu resells are from one of the best manufacturers of those low cost mass produced lasers and have reverse polarity protection. Most of those 300 series types don't and all you need to do to kill one is put the batteries in the wrong way once and the laser is toast/killed.

Luckily now a days reverse polarity protection is standard in most built lasers these days. i remember about 6 years ago it was standard for flashlights but not lasers. even some nice lpf build lasers. All it takes is one time not paying enough attention and accidentally putting in a battery wrong. I did that with a laser Tmack i believe his name was build me. i had it on for half a second before i realized. didnt kill it but reduced the output by half.

 

[LeroyLaserkins]

This was a simple fix and I’m very happy I posted on here. I was bummed I was gonna have to wait along time for a new green laser.

 

[LeroyLaserkins]

green laser working thank-you

switch around the battery polarity, In the green laser the battery - should be facing the head and the + the tail cup

++kudos for the help

 

[Giannis_TDM]

green laser working thank-you



++kudos for the help

No problem! always happy to help.

 

[LeroyLaserkins]

No problem! always happy to help.

hopefully this may help someone else one day. personally was really dumbfounded that this laser wasn’t working. such an simple fix

 

[Giannis_TDM]

turned out the green laser has the opposite battery polarity.

hey do you want to learn why is that too?

 

[LeroyLaserkins]

hey do you want to learn why is that too?

yes i would, ive had a green laser before that took an 18650 and I believe it went in with the positive side facing the laser beam Unlike this 304 green one

 

[Giannis_TDM]

yes i would, ive had a green laser before that took an 18650 and I believe it went in with the positive side facing the laser beam Unlike this 304 green one

Nope In all DPSS Chinese greenies the battery + is facing the tail cup and you ask: Why is that? Here we go!
Its because the diode is case positive meaning that the + pin of the IR pump diode is connected to its metallic case too, So if we were to use the battery case negative like the rest of your lasers it would short out/Not function at all because the driver won't be powered properly because the driver itself regulates on the - rail and actually takes the + input from the case pin.

 

[hakzaw1]

switch around the battery polarity, In the green laser the battery - should be facing the head and the + the tail cup

That was ^^^^ what I was about to add.
afaik either all or most 532s are case positive--so + towards the tailcap.no such 'rule' for other wavelengths BUT all DPSS are case positive I think.
It is possible that your l;aser did not have reverse polarity protection.
SO if you tried first the wrong way --well you know- NOT good.
also I 'THINK' in some lasers the protection mostly aves the diode and may harm just the driver.. (cheaper to replace)


'When in doubt --leave the batts out' (until you know for sure.)
Doing even a 'quicky' test the wrong way or w/o a driver may still be a laser killer. Same with using a battery alone-- no do no do.
Trying both ways is a BAD idea.
These are lasers not Xmas tree lights.

these and other things are why very few sellers allow a replacement.
IF it dies.. very likely owner error.

good luck to you and stay safe!!

hak