The AM Forum
March 28, 2024, 11:31:20 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1] 2 ... 5   Go Down
  Print  
Author Topic: Hit with 6kv yesterday... DON'T trust the Millen connectors!  (Read 53561 times)
0 Members and 1 Guest are viewing this topic.
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« on: December 17, 2018, 11:53:23 AM »

Lucky to be here to write this today.

Yesterday I got hit with 6kv.  Through my hand, out my leg.  Also a small hole in my opposite pinky finger. 

Hand hurt so bad it was on fire for a couple few hours, until the morphine kicked in.

Bought me an overnight stay in the hospital thus far.  Hand hurts still, burns being attended to.

Never trusted the Millen hv connector.......  This amp was complete, bought from someone else.  Was reaching around to move the wire from the line section to the bird.  Plasma arc reached out and hit me three times.

Merry Christmas everyone.  This one will have a very special time for myself and my family.

Be careful friends, fellow hams and homebrewers.  I got hit, all covers on, safety interconnects installed and working and all the screws in this thing.

--Shane
KD6VXI
(from the hospital bed, 17 hours after the fact)

Edited for pics
Logged
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #1 on: December 17, 2018, 11:54:06 AM »

Pic


* 20181216_165023.jpg (4197.6 KB, 4160x3120 - viewed 930 times.)
Logged
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #2 on: December 17, 2018, 11:55:17 AM »

Pic

Have a pic of the exit hole in my leg, but it's too big to post.


* 20181216_164942.jpg (4560.98 KB, 4160x3120 - viewed 767 times.)

* 20181216_134611.jpg (4556.25 KB, 4160x3120 - viewed 793 times.)
Logged
KF7WWW
Member

Offline Offline

Posts: 91


« Reply #3 on: December 17, 2018, 12:16:40 PM »

Its good to hear that your ok!
Ive never been bit with that much, 4400 was the highest for me.. Changed my mood that day.
I certainly hope that wasnt the power supply that you built from the parts you bought from me.. We both know what currents its capable of!

Take care   73's


Sam
Logged
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #4 on: December 17, 2018, 12:41:19 PM »

No, not with the xformer I got from you, but this was no joke, either.  2.5A ccs at 4200 vac.  16x1800uF caps.

Someone else built it.  Doesn't excuse anything but it sure feels better to be able to say that!


Worst thing is, this is one of those injuries 'you hear about'.  Amp was completely done, all screws in it, had been tested.  Was just 'moving a wire' into a more accessible area.

I got really lucky, I don't believe I had a direct strike.  I believe my hand was close enough to cause a plasma arc to start.  I //heard// 3 distinct strikes before I was able to throw my self free.

Just as easily could have been someone's pet, a grounded piece of coax, etc. That got too close to the connector / wire area.

Wake up call, and as you said....  A mood changer!

My nurse is a traveling nurse from Colorado.  Her boyfriend is a W1 lander.  She asked me what had happened, I explained it was from a 'ham radio amp', and she seriously turned white (she's Hispanic)...

Her boyfriend had sent her a pic that afternoon.....  He got the station up at their new house in Denver!   She responded with pics of my hands and my call! Lol.  Poor guy.


--Shane
KD6VXI
Logged
KF7WWW
Member

Offline Offline

Posts: 91


« Reply #5 on: December 17, 2018, 01:15:17 PM »

 Shocked

Um... Yes, Your defiantly lucky to still be here..  112.5 uf Is one hell of a supply to discharge through you and to still have the 2.5 amp grunt with probably a 5 amp peak behind that... Makes my chest hurt from here.. I know that you know your stuff but we all tend to get a little careless around HV.
I have several times found myself reaching into a "hot" hv supply, the few times Ive been bit, Im sure I will have some long term issues from it. You might want to revisit the doc after you heal.. An EKG might be a good thing to pursue just to make sure you dont have any lingering heart damage.
You have to hang out on this planet for years to come, there aren't enough competent techs that will touch the big boy stuff.. Grin
Logged
PA0NVD
Member

Offline Offline

Posts: 615


Nico and Chappie (Chappie is the dog...)


« Reply #6 on: December 17, 2018, 01:46:29 PM »

Happy to hear you came out well Shane, these are no voltages to be careless with. I always worked with voltages up to 12 kV DC up to 150 kW. It made me very careful. My "HV teacher" always told me to learn from an old technician, bad HV technicians don't grow old....
He told me to connect HV always with a coax and in addition a screwed-on ground wire. An isolation issue at the HV coax will always result in a short and the HV can't escape.
Logged
W1ITT
Member

Offline Offline

Posts: 573


« Reply #7 on: December 17, 2018, 02:29:37 PM »

Glad you're here to report the incident Shane.  I never liked the Millen HV connector either.  I use HNs and a proprietary HV connector that has a long leakage path and no chance of exposed conductors to reach out and bite.
I'm curious what the doctors' concerns were after a 6 KV hit.  Were they primarily looking at cardiac electrical stuff?  Do you know if they ran a cardiac enzyme blood test?  (That one checks for cardiac muscle decay products in the blood stream.)  Any concern for immediate internal tissue damage at input and output sites?
Or did they just want to watch you grab a cold water pipe to make sure you were fully discharged?
 de Norm W1ITT
Logged
K1JJ
Contributing
Member
*
Offline Offline

Posts: 8893


"Let's go kayaking, Tommy!" - Yaz


« Reply #8 on: December 17, 2018, 03:57:14 PM »

Wow, pretty nasty hit, Shane.

Fortunately it looks like mostly surface damage.  I'd say the path was spread out over a wider area, which is a good thing, rather than everything going into one small point and exiting at another, thru your heart, head or wherever.

Back in the sweaty summer of 1972, I got my first and worst belt.   800 VDC went from one hand to the other, right thru my chest. My right hand's flesh got torn open because I could not let go. It caused 3rd degree burns, charred flesh, no blood - cauterized. The skin on my index finger was torn open and hanging.  It took months to heal and kept getting infected. I really should have gone for stitches. I was afraid to go near that rig for 2 days.

So, obviously that 6KV accident you had could have easily been fatal if it took the wrong path.

When I look back at all the MANY, MANY risky, dangerous and stupid things I've done - and near-accidents I've had, I know there is a guardian angel watching out for me. You have one too...  There can be no other answer... :-)  

Hope you heal fast, OM.

BTW, I have NEVER trusted any type of slip-on, screw-on feedthrough HV plugs.  I make it real obvious and strong - I use a 2-3" tall ceramic pillar mounted on the chassis for all to see and avoid in the HV area.  A HV lead connected to a HV circuit on a pillar has never failed me.



T
Logged

Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
W1RKW
Contributing
Member
*
Offline Offline

Posts: 4410



« Reply #9 on: December 17, 2018, 04:36:00 PM »

Glad you walked away from it.  Extremely lucky.

2.5kV for me about 20 years ago.  The path was between the back of my hand and thumb on the same hand. The back of my hand was touching the chassis of a PS and my thumb brushed a hot terminal ever so slightly.  Suffered a similar injury to my thumb. A pin hole where the flame shot out. And a burn mark on the back of my hand. Amazing thing was I did not feel it through the rest of my body.  My heart rate did not change. Talk about luck... until a week later when I needed minor surgery on the thumb for a deep tissue infection from dead tissue.  
Logged

Bob
W1RKW
Home of GORT. A buddy of mine named the 813 rig GORT.
His fear was when I turned it on for the first time life on earth would come to a stand still.
WA2SQQ
Contributing
Member
*
Offline Offline

Posts: 1090


« Reply #10 on: December 17, 2018, 04:43:02 PM »

Glad you are ok. Well at least you can list a conductor on your resume! It definitely reaffirms the fact that we are not immortal.
Logged
WBear2GCR
Member

Offline Offline

Posts: 4135


Brrrr- it's cold in the shack! Fire up the BIG RIG


WWW
« Reply #11 on: December 17, 2018, 05:12:18 PM »

Wow, very very very scary stuff.  Shocked

Wonder if you can say if you were touching the Millen connector itself?

Was the rig OFF?

Is there a bleeder on the HV?

If you were not touching the Millen connector, perhaps the insulation on the wire
broke down...

Not sure what the max voltage rating on the Millen connector is...

And, I never liked the Millen HV connector much, I rather think 6kv is probably at the hairy
edge of what it can handle...

Glad you are around to tell us all about it! Complete recovery!

                              _-_-
Logged

_-_- bear WB2GCR                   http://www.bearlabs.com
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #12 on: December 17, 2018, 05:20:46 PM »

Thanks to everyone for the wishes.  It definitely served to WTF up (wake the ....).

I don't believe I got a 'direct' hit....  The 70A breaker in the power supply didn't trip nor did the panel breaker, an adjustable magnetic hydraulic set to 60A.  After I 'walked it off', I went out and shut the main panel to the shop down.  Feels like it will be a minute or two before I head back out.

My big dummy load has an HN connector.  I'll have to look into it for HV.  I've used rf style connectors for kilovolt stuff, but nothing over maybe 1.2kv.

I did get a small burn on my index finger on my rt hand somehow.  Almost like step voltage type burn, looks like a kernel of yellow corn right up against my nail.  I've no idea why, unless it was Corona? Lol.

Conductor....  Hahahaha.  I'll have to tell my boss that, although he told me find a new hobby last night.  As an electrician, he feels I'm around voltage too much already.

I think the worst effect is to my kids.  My oldest is pretty shook up.  Definately time to reassess a few things.


Bear, the rig was on, covers installed, etc.  I had already loaded it up, unkeyed and didn't like how a wire was 'dangling' around the back (from a line section to the bird meter).  I went to brush it out of the way, and 6kv jumped...  I think if I would have had my hand anywhere closer I'd be dead.  It did hit me a total of three times before I was able to throw myself free, so I can say the plasma path wasn't continuous.  I think the exit through my leg was probably the first strike. 

Scary thing was the damage to my rt hand.  It was in my back pocket.....  So I KNOW I had some voltage go thriugh my heart.

I was admitted through 'urgent care'.  My fiancee pretty much insisted I at least get checked out.  The doc upon hearing what happened spoke to hospital admitting (the urgent care was physically connected) and they said to admit me.  They hooked me up to a remote heart monitor for 24 hours, had an iv drop of saline (bag and a half).  They also did a full ekg when I was admitted, and chest x rays.  The nurse at urgent care has a W1 call boyfriend who sent her pics of his station he set up yesterday.  Her response was a pic of my hand and my call lol.

If I missed anyone's questions, feel free to poke me and say hey!  Lol.

Again, thanks everyone.  

--Shane
KD6VXI
Logged
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #13 on: December 17, 2018, 05:25:09 PM »

Oh, Sam.  As to follow up care.  Yes, they wouldn't let me leave until THEY (hospital) set my follow up appt with my primary care.  Like you said, they also stated:  their is the possibility of something not seen today, or that manifests itself later.  The doc left work up to me.....  He said physically I appear OK but if I have any doubts, pain or anything else...  Don't.


Also.  Electric chair:  cruel and unusual punishment.  🤔🤔🤔. Shyte hurt!

--Shane
KD6VXI

Logged
KF7WWW
Member

Offline Offline

Posts: 91


« Reply #14 on: December 17, 2018, 07:00:09 PM »

Shane

Good, Definitely need at least one follow up check out, probably one 6 months from then also.

Electric chair.... Well, you forgot to wet the sponge....



73's


Sam
Logged
KK4YY
Member

Offline Offline

Posts: 565


Your best isn't as good as you can be.


« Reply #15 on: December 17, 2018, 07:49:38 PM »

Shane,

Wow. Very scary.

2KV knocked me on right on my azz and I didn't feel quite right until the next day. I was in my 20's back then, wouldn't want to take that hit today.

You must have unfinished work to do in this world.

I can't recommend a good connector, but I think a shielded (and grounded) cable like RG-8 would be safer. See application note attached.

Stay safe,
Don

* AN-07.pdf (370.65 KB - downloaded 321 times.)
Logged

All your worries won't add a day to your life, or make the ones you have any happier.
K1JJ
Contributing
Member
*
Offline Offline

Posts: 8893


"Let's go kayaking, Tommy!" - Yaz


« Reply #16 on: December 17, 2018, 09:00:39 PM »

You said:

"I don't believe I got a 'direct' hit....  The 70A breaker in the power supply didn't trip nor did the panel breaker, an adjustable magnetic hydraulic set to 60A."


Shane,

BTW when applied to the right place on the body, it only takes about 18 mA  at 2KV to kill someone.  That's just 36 watts.  (or much LESS voltage - whatever it takes to draw 18 mA thru the critical body areas.)  Your 70A breaker at 240V = 16,800 watts.   The breaker didn't even know you were there... :-)    Those movies showing electrocutions with the lights dimming and transformers humming are a crock of bull hype...   IE, primary fusing and breakers will not protect anyone, even on a more sensitive, smaller 50 watt Novice tube rig.  Has anyone EVER seen a breaker or fuse blow when getting belted on a tube TV, tube audio amplifier, small ham TX or tube receiver, etc? ? I doubt it...   This is something to remember.

The only thing that usually saves anyone is that they were somehow able to get away and break the circuit.... period.  As the body cooks, the current will increase (and become even more deadly) as the flesh carbonizes and the path resistance goes down.   There is no small-signal fail-safe trip protection from HV to chassis ground, so we are screwed.



So glad you are safe, OM.

T
Logged

Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
KB2WIG
Contributing
Member
*
Offline Offline

Posts: 4484



« Reply #17 on: December 17, 2018, 09:38:52 PM »



"  had an iv drop of saline (bag and a half).  "

So, I guess they figured that you were not conductive enough.


klc
Logged

What? Me worry?
KD6VXI
Contributing
Member
*
Offline Offline

Posts: 2648


Making AM GREAT Again!


« Reply #18 on: December 17, 2018, 09:47:35 PM »

Hahahaha!  Yeah, well.

A good friend of mine was a conductor for Union Pacific for years....  Guess we have something in common now?

--Shane
KD6VXI
Logged
Detroit47
Member

Offline Offline

Posts: 644



« Reply #19 on: December 17, 2018, 09:53:24 PM »

Dude you rode the lightning What's up with that you trying to visit Golden Arms or Dragon Base. Don't forget the big man on reservation. I won't lecture you know better. That was just a little warning. I am glad you are above ground. I am sure they did an EKG. You know the thing that is scary if you had internal arcing. that happens in your chest. The bad thing is when tissue dies and they don't see it. Did you get that funky metallic taste out of your mouth yet.
47
Logged
K6JEK
Contributing
Member
*
Offline Offline

Posts: 1189


RF in the shack


« Reply #20 on: December 18, 2018, 12:32:57 AM »

Congratulations on surviving. Down to eight lives now. Maybe MOSFETs are in your future.
Logged
Opcom
Patrick J. / KD5OEI
Contributing
Member
*
Offline Offline

Posts: 8308



WWW
« Reply #21 on: December 18, 2018, 12:36:48 AM »

I'm glad you are 'OK' after that. When you feel like it, could you please post (pr0n) pics of the amp and PS, including the area of the Millen connector and Bird line?

My 3CX AM project is kinda stalled right now but I am still trying to be sure that any HV connectors are enclosed within the rack with doors shut, and opening the doors shuts off the HV. Now I can understand that the line section and any cables should not be close to the HV terminal if it could be avoided, I appreciate that. There are always some risky times when trying to get something to work and It might be worth it to hook up a strobe that flashes for me when the HV contactor is energized as well as an extra HV meter in the back of the thing as meters are cheap enough, boxes of them here. That project has the stock Henry RF generator HV connector right now.

The tabletop 3CX amp here is another matter. It has also a Millen HV connection exposed on the back, fed through HV wire surrounded by braid tube from RG8, with a ground lug. There are a couple inches of HV wire and the Millen connector exposed outside the enclosure and about 4500V there. I don't like that kind of hookup. I've never trusted HV connectors to be touched in any way let alone with HV enough to arc.

Someone on this message board once said that there is a big difference for arcing, corona, and problems from 'conductive dirt' when things get above about 3 or 4 KV.

I work by myself and am nervous about low B+ voltage ranges and possibly afraid of real plate voltage. Not sure it is fear but it is some kind of excitement feeling and always on my mind when the HV is being worked with to the point I check/look at the HV meter is at zero 2 or 3 times before grounding the HV with a hook and fiddling about.

Again very happy you only got a nasty shock. Merry Christmas! The gift of life!
Logged

Radio Candelstein - Flagship Station of the NRK Radio Network.
WA2SQQ
Contributing
Member
*
Offline Offline

Posts: 1090


« Reply #22 on: December 18, 2018, 10:29:48 AM »

Had a very close friend, years ago, WA2LSE. Bill was admitted to the hospital for an apparent heart attack. When he woke up he asked the doctor what happened. The doctor was reluctant at that moment to say how severe it was. Bill looked at the doc and said, I know you used the paddles on me - I know what it feels like to be knocked on my a** by electricity! I can only claim to getting bit by ~800V, inside a power supply for my friends ART-13. IT taught me RESPECT!
Logged
K1JJ
Contributing
Member
*
Offline Offline

Posts: 8893


"Let's go kayaking, Tommy!" - Yaz


« Reply #23 on: December 18, 2018, 11:31:04 AM »

Had a very close friend, years ago, WA2LSE. Bill was admitted to the hospital for an apparent heart attack. When he woke up he asked the doctor what happened. The doctor was reluctant at that moment to say how severe it was. Bill looked at the doc and said, I know you used the paddles on me - I know what it feels like to be knocked on my a** by electricity! I can only claim to getting bit by ~800V, inside a power supply for my friends ART-13. IT taught me RESPECT!


Yep, thankfully most of us learned that lesson very young. Perhaps starting with sticking our finger into an AC wall socket.  Though in your case, 800 VDC is no picnic if it hits you right.


Here's the goods:  Take a DC ohm meter and grab it in each hand. What do you read, 200K? Lots of dead skin there.      Now put it across your tongue… 10K? Moist, tender skin.     (That's what I just read measuring myself)

So the initial shock will depend much on what type of skin the current initially hits and if the layers underneath  have a lot of moisture or not. I can picture a 2KV shock blowing a tonque clean off... and you might die from collateral mouth/throat damage.    While a 2KV shock in the hands may give you a chance to escape with some surface damage. In the real world of accidents, it's really a random crap shoot as to what skin and organs underneath are in the path... and how long the current stays on to burn a more conductive, damaging path.

Picture a live 2KV supply - clip lead various 10 watt power resistors across it in succession.  First 1 meg... nothing happens.   Then 100K... starts to smoke after 10 seconds.  10K... explosion in 5 seconds....    1K, immediate firecraker.......   100 ohms... cherry bomb.   It all depends where on the body the current hits you.

I've read that a very large current thru the heart (> 50++ mA) will cause the heart muscles and tendons to react so violently that they literally tear themselves a part from the epileptic movements.  (The heart is designed to receive signals from the brain in the millivolt level.)  There's usually no recovery from that massive overload.  

As I get older and look at the check list to go from one big rig to another, I realize the chance to make mistakes is increasing.  Maybe the class E and SDR stuff does have a clean advantage there... :-)

T
Logged

Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
W7TFO
WTF-OVER in 7 land Dennis
Contributing
Member
*
Offline Offline

Posts: 2521


IN A TRIODE NO ONE CAN HEAR YOUR SCREEN


WWW
« Reply #24 on: December 18, 2018, 11:52:49 AM »

The ubiquitous 7-16 metric coax connector system works very well for HV, is dirt cheap, too.

Good to hear you'll be OK.

73DG
Logged

Just pacing the Farady cage...
Pages: [1] 2 ... 5   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.071 seconds with 19 queries.