ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (Scott35), 271 guests, and 19 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Jun 2003
Posts: 1,143
D
DougW Offline OP
Member
Nods to the linemen amongst us! Here's a quick one about a FD "service" call turned mini-class.

Got a call at the FD today for a "transformer on fire". We were coming back form another call, and were only a few blocks away.

When we arrived on location, we looked up, expecting to see the "ash can" ablaze, with that lovely (and tasty) oil smoke, but we see...nothing. Spot an older gentleman on the curb, frantically waving and pointing.

Turns out that this guy had seen a fuse on a 12.5 KV line blow, and fire had shot out of it. Now there was no power in the area. We called the PoCo, and waited. I explained to the gentleman that it was a fuse, that the "real" problem had to be farther down the line. My boss showed up and left me with the pickup truck, and gave me "babysitting" duty since "...you're the electrician on the department".

After a while, PoCo showed up, found that a bird had crossed to ground on a xformer a few poles down - that fuse had blown, and when the system tried to "re-proof" (reset) a few moments later, the fuse by the caller's house had lit up.

The lineman went up in the bucket, and changed out the xformer fuse (snap)... then backed down the alley and discovered that the "burning" fuse (which looked intact) had actually arc welded inside the tube, so it didn't "pop".

Came up and ID'd myself to the lineman when he was done (Hmm... big red truck w/FD on it - no, told him I was a residential spark), and asked how these things worked, since the closest I get to his turf is new services.

Got into a discussion about rope / expulsion(?) fuses, and exactly how the spring loaded fuses on power poles work. He also explained the different layout of the ComEd system, their system status reporting capabilities, and how their OCP works on their lines. I'll tell you guys, watching that dude replace the fuse from the ground using a wobbly 28' fiberglass stick reminded me of a microsurgeon. AMAZING!

All in all, not a bad learning session! [Linked Image]

Joined: Aug 2002
Posts: 1,081
T
Member
I'll never forget the day I saw lightning hit a fuse. After the storm, around 4 in the morning, I heard a loud truck outside. Went out to investigate and there was the PoCo changing out the fuse. They let me keep the old one [Linked Image]

Joined: Apr 2004
Posts: 20
O
Member
On a service upgrade I worked on last year, I was around when the Linemen came. We were chatting and one of them told me that the creepiest thing that ever happened to him was the first time he got next to a 155,000v transmission line that his Kleins literally started to hum and vibrate in his gloves! [Linked Image] That deepened my respect for our line of work and the safety precautions we must always practice.

Joined: Apr 2002
Posts: 2,527
B
Moderator
Many crossarm-mounted medium-voltage fuses are of the expulsion type, and will “vent” noisily on one or both ends of the fuse tube. The bottom end is often open, but at higher fault duties, the top cap is machined to act as a pressure-relief device and vent out of the top of the fuse tube also. However short lived, the arc energy can be sobering.

Joined: Feb 2003
Posts: 939
F
Member
i have few of my freinds they do work on poco and pretty often i call them to help me with service drop[s] and few other oddballs and fwe time they did call me to come out and help some coumster to deal with service drop .

i never forget many years ago , we have major storm kinda like wind shear/ torando and rip 8 miles of brand new 3 phase line and broke over 60 post and one power company they know me very well and they did call me and help them to survey the damage and one thing it was unuseall for reg sparky to work with poco together to get the mess clean up. we been working for a full week to cut a bunch of trees and move damaged lines out the way and restring new one and we have to inspecet each drop for each building for any damagaed and talk to the owner for nessecary repairs and myself i did repaired 22 drops the other electrican i know him he did 32 drops [ he do home and i did commercal sides] and i did learn a bit from them and they learn a bit from us too it was very instering crash course but we work like team. and i have few med voltage fuse with me for collection it was fiberglass tube spring loader type or slinger type.

i wish i can find the photo but i dont rember where i put that photo now it was way back in June 87 if i recalled it right btw my propety was hit very hard and i got hardest hit i lost over 80 trees in spot but the house is good shape .

merci , marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Joined: Mar 2004
Posts: 76
M
Member
I had the honor of being a POCO Line Tech for 10 years, & it was the greatest job on earth. A lot of hazards, & weather problems but I loved it.
Working with 12kv most days keeps you on your toes, but done correctly it isn't impossible to have a long, safe, career.
Modern methods & PPE have made it a different Trade than it was a few years ago.


Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5