Hello does someone know any way to test a Power Supply without a tube on the machine? My tube is damaged and i want to test the power supply if works
Thereās no practical substitute.
Power supplies are relatively cheap and readily available: just buy one and skip the whole life-endangering process of trying to gimmick up a water-cooled negative-resistance high-voltage instrumented dummy load that isnāt a COā laser tube.
Source: been there, didnāt do that.
Basically its a method using GWEIKE laser technicians to test power supplies. There is video showing a procedure
Perching a ceramic wire-wound resistor on a plywood slab and connecting it to a 15 kV supply with low-voltage exposed clip leads is not recommended practice.
Stipulated: I have a morbid fear of dying. If Iām going to do something that risky, itās gotta have a much bigger payoff.
It appears to be standard practice thereā¦ 
I donāt like to scare people, so I try to tell them the truthā¦
I know of nobody that has died of getting across an lpsā¦ Not saying you canāt, but itās much more likely you will get yourself killed by getting across the mains going into your machine, rather than across the high voltage output.
I know many āradioā people that have gotten across 20kV with tube rigsā¦ I am one of those ā¦ we are not dead. Thousands work with neon lightsā¦ all very high voltage, deaths here, again, come from the mains, not the high voltage.
Almost 80% of the people that are electrocuted in the US is from the standard mains, not some kV conversion. Itās usually the 120V half ā¦ this is one of the danger areas that people ignore.
That said, itās not going to be pleasant to become the ādummyā load of an lps.
Anytime you get a āshockā, the possibility of death is a realityā¦
Most hobbyists take things apartā¦ itās only natural, but understand the basic risk of just a very unpleasant shock.
@ednisley pointed out, for the headache of fixing one, itās much more effective to replace itā¦ Which gives you one to take apartā¦ 
I would not replace it if I were getting a new tube. I would not have replaced the tube without the proper determination of the faulty component ā¦ I hope.
It you connect it and it doesnāt work, then become suspicious of the lpsā¦ Otherwise the āconsumableā is the tube, not the electronics.
I have a high voltage meter on my machineā¦
Good luck
I am not going to hold the cables when testing. Also i work with Neon so 10.000V is usual for me to work with, neon also work around 23-25 mA too but AC. Ampere kills for sure. People are kiled from 110-220-400v network voltage for sure.
It never occurred to me that neon was powered by AC. Never even questioned it. Learned something today so I got that going for me. Thank you.
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Well, yeah, they all stop posting right after that. 
What might be standard practice for somebody āskilled in the artā or at least familiar with the situation is a completely inappropriate recommendation for what seems to be someoneās first encounter with a voltage capable of reaching out through an inch of clear air to shake your hand.
Might not kill ya, but it might just reboot your ticker ā¦ and youāre definitely gonna do an extra load of laundry that afternoon.
.
I did mention they probably wontā like the experienceā¦
I mean the original neon light. Not the newly led neon flex of course. Original neon are glass made with neon or argon gas inside. High voltage ionises the gas and then lights on
You never took apart some junk appliance with a neon light to indicate powerā¦?
Most of those are just a neon + resistor across the mainsā¦ Used to by these by the poundā¦
Was always fascinated by neon displays but never had an occasion to inspect one. Never had access to neon of any kind in appliance or otherwise. Knew how they worked in principle but never questioned the electrical side of it. Just knew they werenāt very power efficient.
The days are long past, but my friends and I liked to find old television sets and disassemble themā¦ lots of capacitors, resistors, tubes and so on. The CRT display tube of a television can hold a charge for rather longer than you might expect, and if you didnāt get it properly discharged, you might find yourself halfway across the room after accidentally touching the wrong leads.
First started with radio, I scavenged a bunch of tvās for the litz wireā¦
I know this for CRT Tvs. They work with high voltage. Also capacitors can give you a good hit if they are charged
Not related to the topic itselfā¦
But this ātesting methodā looks alot like those CNC spindle kits they sell on the internetā¦ 500W spindle 100V with a chinese PSU 0-110V with non isolated mains it works well until it doesnāt, either you get too confortable and slack or you just not focused enough and ZAPPPPPPP.
Smoked a similar one of theseā¦ learned that I should measure the difference between the grounds before assuming anything.
Then I got one of theseā¦ fortunately I measured it ā¦ just over half the mains voltageā¦ 
i have taken the extra step, yes it costed me about 30% more than the 100V kit but i got myself a 500W 48V spindle with a 0-48V named brand PSU.
besides the danger of the PSU itself they cause alot of electric noise not good for the Steppers and mainboard of the CNC.
But Hey @Jimi if you dont wanna invest in a new PSU try to find locally someone that can lend you one for testing, on the other hand if you are really sure that your tube is broken, buy a new tube first install it and then you have confirmation about your PSU.
I am just afraid the chance that the psu is defective and burn my new tube for some reason