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Jonathan Bowen
03-17-2014, 6:30 PM
So... to cut a horrible long story short. Hurricane will not replace my tube. So I decided to upgrade to a 60 Watt tube... I then broke the first one because my PVC extension wasn't a great idea. I put a flange on and then a 3" T piece and it ended up being a fraction of an inch too small and fit without the boot but I put it on with the boot on and it cracked the tube. Now my second tube has come in and I got a 4" pipe instead of a 3" one and it fits with enough wiggle room to spare if I'm careful. All is good and then I fire the tube the first time and don't get much out of it. A bit of a fizzle and about 4.2 amps. Power supply is brand new but was causing another 40 watt tube (that was close to end of life and now is) to stutter bad on startup. The tech at light object thinks I jacked up the tube by soldering the connections onto it. I've always done this and read up on it on this forum. I'm really quick and wire wrap the cable then basically glob solder onto it hold it in place. He seems to think it is leaking but I'm trying to prove that wrong by waiting and checking the amps over time. It doesn't seem to be dropping at all so I suspect its not leaking. I REALLY don't want to buy another tube... I also really need to get this running fast. Any ideas? Not sure how I can test the power supply but the test button on the power supply and the laser button on the controller both have the same result.

It's a 40 Watt Hurricane Agnes (Gwieke) with a lightobject 40/60 watt power supply and new 60 watt tube.

Dave Sheldrake
03-17-2014, 7:03 PM
Cascading problem by the sound of it Jon,

Possibles,

Trigger wire to the card is loose,(it's a 5V rail)
Tube is partly DOA,
Tube vented when soldering,
PSU was damaged by previous tube,
PSU is adjusted for 40 watt output and not 60 (there is a POT on the underside to adjust amps),

When a tube vents it usually kills it dead, they rarely if ever partly leak, Check your trigger wire at both ends to ensure a good contact then I'd be looking at connecting a big resistor to test the PSU (and adjust where required / if required). Croc clips or the brass bit from a choco block are very good for connecting the wires to the tube and avoid the potential for problems when soldering (the electrodes are tungsten so can't really be *soldered* as such)

May also be a good idea to check the voltage from the trigger wire to ensure that's giving the correct signal.

cheers

Dave

Jonathan Bowen
03-17-2014, 7:14 PM
How can the previous tube damage it? I did notice that I had it turned up a lot higher then the last tube but I forgot to drop it down after the second tube was installed. The other tube was registering 11 amps no matter what power was set to and it was stuttering till it warmed up. I didn't think to lower it because the amps were not moving. I don't think I have room for a choco block. I can probably get an alligator in there. I kinda panicked when he said I could destroy a tube by soldering it but I had seen posts about it and thought it was safe if I kept the solder heat to a minimum. At this point sales have dropped so far that I haven't even grossed enough to pay for 3 tubes this month... Not to mention the shipping time for yet another tube.

EDIT: There is no Pot. I am using the test button on the power supply or the laser both seem to put it to full output. Or at least they did. The 40 Watt was getting very weak and I really couldn't cut anything with it. They also said it was tested before it left.

EDIT2: Well it's not the connections. However the power supply is making some odd noises. I just installed some alligator clips and nothing has changed. Still the same amps and hardly any light in the tube.

Dan Hintz
03-17-2014, 8:48 PM
Dead (dying?) PSU... replace it.

Dave Sheldrake
03-17-2014, 9:26 PM
Sounds like the PSU as Dan says Jon, on occasion a faulty tube can cause the PSU to work above it's safe limit causing all manner of nasties inside it hence my "cascading" problem thought (Tube dies/ kills psu / psu kills new tube/ now dead tube makes you think PSU is dead etc etc etc) you end up tail chasing not knowing which part is actually at fault and damaging new parts with the existing damaged items.

If the tube is lasing then it's unlikely to be leaking or has leaked, when they go they tend to just be dead with nothing coming out.

I'll see if I can find the spec of resistor you need to test the PSU (current) I'd avoid using the PSU on your new tube until it's been tested though.

cheers

Dave

Jonathan Bowen
03-18-2014, 11:15 AM
Thanks Guys. Hopefully a new PSU fixes it. I have 2 40 Watts and 1 60 Watts. I temporarily connected all of them and the 40s all show about 6 amps and the 60 is about 4 amps. All show similar lighting issues. The 40s are all suspected as bad.

Dave Sheldrake
03-18-2014, 12:23 PM
Before ordering a new PSU Jon , it may be a good idea to test the existing psu for total current, need to rule out a bad tube (again) before maybe spending on a new psu, I'm pretty sure it is the psu but better safe than sorry

cheers

Dave

Jonathan Bowen
03-18-2014, 6:48 PM
Well lightobject is covering the cost of the power supply. So I'm going to start there and see what happens. I don't really have the equipment to test the high voltage safely.

Dave Sheldrake
03-18-2014, 9:28 PM
Current Jon, not voltage, a big resistor can be placed instead of the tube to measure the amperage of the PSU. The voltage is less of a problem on PSU's :)

I'll try and dig out the spec of the resistor required....WEike supply them with all new machines so I'll ask Lucy if she knows what it is.

cheers

Dave