Taking apart a large transformer

No, but some of that research -- or more correctly the conclusions drawn from that research -- was later proven incorrect. This is something the left-wing, atheist, tree-hugging hippies will not admit.

(As an aside, both sides in the environmental debate have made a cottage industry out of discrediting scientific studies supporting the other side's position. It takes some very careful reading to separate the solidly supported positions from the speculative ones and those from the junk science.)

--RC "Sometimes history doesn't repeat itself. It just yells 'can't you remember anything I've told you?' and lets fly with a club. -- John W. Cambell Jr.

It was pretty obvious from the post that OP was dealing with a dry transformer. You couldn't see the construction details he was describing in an oil-filled transformer.

Considering that you didn't know, wouldn't it have been more reasonable to ask first?

Remember, two conditions had to be met before the OPs transformer could be considered dangerous. 1) It had to contain oil and 2) It had to be manufactured more than about 30 years ago.

To my mind it's worth determining at least condition 1 before sounding the alarm.

--RC

"Sometimes history doesn't repeat itself. It just yells 'can't you remember anything I've told you?' and lets fly with a club. -- John W. Cambell Jr.

For those who are interested in a little of the history of PCBs I work for a utility that has some experience with it.

Firstly, size doesn't matter, it was everywhere at one time, and ignoramus's original post did not mention if the transformer was dry or not. So I think Doug's response to be wary of PCBs was the right thing to suggest, given the possible dangers involved.

PCBs were the answer to a maidens prayer for transformer and capacitor manufacturers, since it had much better heat transfer characteristics combined with excellent dielectric strength. Plus it allowed more compact designs, and a cheaper overall product cost. All was well in transformer and capacitor land until a couple of incidents that drew attention to some of PCB environmental effects.

One incident, came about because PCBs look and smell remarkably like cooking oil, somewhere ( Japan I think ) a barrel of it found its way into a restaurant and it was used to cook food. A number people were hospitalised from its effects, burning of the mouth, throat etc.

Another incident involved a fire in a basement substation in a high rise building in the US. Although it is hard to burn, a fault in the transformer set it alight, and the buildings airconditioning system pumped the smoke from the fire through the building. PCB's produce dioxin when they burn, and the building was contaminated with dioxin. I'm not sure the mess has ever been cleaned up.

Once they started looking at the chemical, they found that it had the property of being very stable, and of accumulating in the food chain. If someone did dump it in a lake, it would still be in the lake 500 years later, most likely in the fish at the top of the food chain.

Experience in our own area was with a customer who bought us a sample capacitor to have tested. They had been asleep in bed, hot night with the fan on, when a capacitor in their ceiling fan leaked PCB's on to them. They had fairly serious skin reactions on their faces, necks, and legs, like a reaction to strong bleach, although the reaction was not immediate. The fellow who bought us the capacitor had the burns, so I've actually seen the effects of pure PCB.

We removed all our PCB capacitors from our network, and replaced them with non PCB types. We stockpiled these for disposal on an incinerator ship which cruised the world destroying the PCBs by burning them at exteremly high temperatures, to destroy the dioxin, out at sea, since it was too dangerous to attempt it on land. Funny thing was the ships kept sinking, the cynic in me thinks it must have been cheaper to load up an old ship to the gunnels with the suff, and sink it rather than actually burn it.

While we had no PCB transformers on our network, we acquired a network which did have some. The problem was that maintenance processes had cross contaminated a lot of other transformers with the stuff, and at one stage the EPA here had set a limit of 5 parts per million contamination of PCB before the oil was clasified as hazardous. I believe it is now at 20 ppm. I believe this to be a major over reaction to risks involved, it's the pure stuff that needs to be treated with respect.

While there is a fair bit of hysteria surrounding PCBs, there are some real risks with the pure stuff that people playing with old transformers and capacitors need to be wary of.

regards,

John

It is a labor intensive operation. I take a knife, and using a light hammer, tap the blade between the laminations peeling them off one by one. The transformer might be worth more to someone as a transformer.

Kevin Gallimore

Thanx for the warning, I was not aware that there still might som PCBs arround in old oil filled transformers and old capacitors so I'll keep that in mind next time I go shopping at the local scrapheap :-)

/Morten

Thank you for an extremely interesting article.

If you mean bury it? NO! It is insulated copper probably!

Polysol insulation will burn off, Polythermaleze will burn off with a lot of heat, Formel insulation will probably not come off with any fire. These coatings are usually made to withstand severe heat in use.

You could use it for a long wave antenae or how about a lightning collector to power that 25W bulb for a few seconds with the $100K in equipment to catch that once in a lifetime strike?...LOL

Wind a huge Tesla coil on your roof and show the neighbours your nuts! (or drop your pants when they are looking)

Can't this tranformer be used by somebody to generate a second 120V from a single phase 120V inverter? It sounds pretty beefy.

BTW: once you knock the wedge out of the coil form the laminations will be easier to get out. This keeps them from buzzing until the varnish and other impregnations go into it.

You may consider it a "minor ailment", but have you seen the photos of that Ruskie politician who was purportedly poisoned with dioxin? A year ago he looked about like baby faced John Edwards, now he looks more like a puffy faced, acne ridden Andy Rooney...

DJ

What are the voltages (and type) on the capacitors? I may be interested.

I am mystified as to how they manage to put the windings on Toroids.

The Copper wire can be used as Grounding but you must check the diameter required against the load it is intened to Ground, this can be achieved by twisting many strands of it together of course (as with any other type of wire).

As for getting the wire off a laminated transformer in one peice, whew?

Most of my component stock is derrived from this sort of venture and that odd screw is very usefull to have around if you need one!

----------------------------------------------------------------------- Ashley Clarke

I thought we were talking PCBs?

Interestingly enough, they use a toroid winding machine. A hoop is split to fit through the core. The hoop is then used as a carrier to wrap the wire around the core.

You quoted me and answered my post in the thread.

No, I will use it as a grounding wire leading to the ground bar at my main panel.

What is that?

It has a lot of connectors. I ppulled another, isolation looking transformer (1:1) from the unit, will probably sell that.

This one looks like a multi voltage unit.

thanks for the tip!

No deaths? OK. But, why is it considered dangerous?

But the GUY who disassembled the transformers is okay, right?

Maybe there's PCBs. Maybe not. If there are PCBs, there might be enough to be detectable. If so, diluted 1-trillion-to-one in a nearby pond might be sufficient to give one fish a headache.

Bah! Who cares?

This is Turtle.

i , first before starting to take apart this transformer contact your Medical insurance company and add on a Cancer Policy for you and the family members for your may need it if you spill any of this liquid at your house or on you. The transformer oil in not cancer causing stuff till it is used over a year or so and then it become PCB . the stuff is activated by the electricity going through it and become a Cancer causing stuff after they have been used. Now here is a chance to get rid of a unwanted Brother in law or kind folks by just getting them to take it apart and get the oil on them. In Short order your in the class of getting cancer soon.

So if you interested in keeping your family safe and not have cancer. You need to have it hauled off to the Power company work station and dump it out when they are not looking and they have the means to dispose of it properly. There maybe $30 or $40 of copper in it but having Cancer will wipe out that profit real fast.

i , DON"T TOUCH THAT STUFF AND GET RID OF IT.

TURTLE

I've heard OLD veteran teachers say they think there's something in the water - people no longer have reading comprehension skills. Luckily, you and two others here seem to escaped this fate.