I don't see any ground point on the body of the transformer.

That pole looks like it's been there a while, I see it is starting to split down the side.

I've seen similar looking transformers in old parts of Santa Ana and Los Angeles in neighborhoods dating back to 1900 - 1920's

From what I can see, it might be the bushing on the right side.

I have seen a fair number of these old guys over the years. I have alway had a question about them, which perhaps someone might be able to answer. I have seen some of these pots with long leads extending from the insulators on the HV and LV sides, and I have also seen very short leads (usually from the LV side only), with splices made to additional conductors. Question; were these transformers manufactured with long leads permanently connected to the internal windings and then brought out through the insulators, or were there connector terminals inside where conductors could be attached and brought out?

In any event, those porcelain brown or white insulators are a treasure.

Mike (mamills)

Hi,

I've seen some pictures and drawings in old electrical books of transformer connections of these old units. From what I can tell, These old transformers had terminal blocks inside where taps could be reconnected / relinked for different primary voltages and one was able to connect the secondary for either series or parallel or series with a tap for the neutral for supplying a 120/240 volt service. Leads were already preattached to the terminals, as portrayed in an old advertisement for GE I seen once. I would assume that these connections would have been modified (If needed)either at the factory, or at the POCO's shop, and not on the job. Even in modern times this fact can probably account for the short leads that you (and I) have seen. I have seen them mainly when you can tell that there had been some work done on the secondary, such as being upgraded to triplex or such. It would obviously be much easier to splice and not open up the pot.

Regarding the picture, I don't see any primary cutout. That seems odd, because the transformer does not appear to be self protected. I'm just guessing, but just based on the size of the primary bushings and insulator on the pole, I'd say this transformer is on a 7,200 V line. (Probably rated 6,600 V)Almost all of these old transformers I seen were connected to 2400 V lines (either 4160Y/2400 or 2400 delta)

Yes, the old distribution transformers had pigtail leads that were continuous from inside the "can" to the outside. They passed through hollow porcelain bushings, and the space between the bushing and the conductor was sealed with something called "compound" (a mysterious substance which had myriad uses in 20th-century electrical practice).

I believe the overhanging top of the can (a "signature" of Westinghouse transformers, though other brands may have had it as well) was intended to shield the bushings from rain.

PCB's?

Kale:

Are you wondering if it has PCB issues? Or, asking about PCB's??

The POCO xfrs here (NJ) were tagged 'NO-PCB's' for 'clean' ones; and all the non-clean ones were swapped out.

The oil within many if not most OLD transformers contained
PCB's (Polyclorinated bi-phenyls). That is a controlled hazardous item, which has caused large amount of pollution/contamination.

It was used a lot in xfr oil, and OLD magnetic ballasts. The 'newer" mag ballasts were marked "no PCB's" or "Non-PCB"

Large xfrs were 'treated/flushed' and refilled with non-PCB oil. This process did not totally eliminate the PCB contamination, it lowered the 'count' to levels acceptable to the US EPA/DEP standards.

'Old' ballasts that contained PCB's were treated as regulated hazardous waste, and required packaging into a steel drum, sealable lid, and a LOT of EPA/DEP documentation. Needless to say, this was and still is a expensive proposition to dispose of legally.

I had (customer owned) 9 'mat' setup 500Kva xfrs 'cleaned', and 3-750Kva that had to be 'disposed'. The 3x750 Kva removal/documentation/disposal by a Lic Haz Waste Disposal company was in excess of $15k, back in '81.

Just curious John, do you know what the hazardous waste disposal companies do to get rid of PCB contaminated stuff? What do they do with the old PCB oil?

Going by memory, the xfrs were set in containment trays, pumped down into 55 gal double wall drums, sealed, tagged and paper trailed to an incineration plant in Ky or Ohio.

The xfr bodies were re-plugged/sealed, shrink wrapped, put on flatbed truck to be incinerated. All was documented, and it is about 25 lbs of paper.

THe old ballasts met the same demize; incineration; I believe it was about $500 per steel drum.

Now...it's fluorescent bulbs and HID lamps; MUST be recycled here in NJ

Incinerator for PCB's

At least Mercury, while toxic, can be reclaimed and reused.

You will find a lot of info on PCB disposal (legal) by googleing 'PCB Disposal'. There's an EPA/DEP site with a lot of info.

There is still a haunting of PCB contamination in the Hudson River (lower) and the Passaic River (NJ) leading into the Newark shipping terminals. It rears it head everytime dredging the channels comes up for public comments. Besides PCB's there's also remnants of Agent Orange from the Vietman era.

PCB's were outlawed in the mid to late 70's.

Regarding the dredging stirring up old contaminants, back in '86 when the carrier I was on needed an emergency dry-dock in SF bay, the local environmentalists got a little bent out of shape when it was disclosed that the dredging to open access to the dry-dock stirred up radioactive contamination (among other materials) that had settled in the bay from decontaminating the 1950's atomic blast observer ships.

No, I do not know what happened to the dredging spoils.

Larry C

Gee John, I had no idea it was that complicated and that expensive to dispose of PCB and things containing PCB. Nasty stuff, my instructor in electrical class said whenever electrical equipment containing PCB blew they had to have hazmat come out. I read on the internet PCB production was banned in the 70's.

Packrat:
Yes, it is $$$$.

Also, as a side note the fluorescent lamps and HID lamps are 'supposed' to be legally recycled. It's sort of in effect here in NJ, but the proverbial stuff is going to hit the impeller soon.

Recycle fees for lamps are a cost a lot of the sparkies and building owners are not aware of yet!

I agree with you on recycling those light bulbs, out here for recycling it's only #1 and #2 plastic, paper, cardboard, aluminum and tin cans; those are the ones I remember anyway. They'll take scrap aluminum, steel, copper and galvanized but those have to be taken directly to Pacific Steel and Recycling. They won't take glass though which is a shame, I wish they would.

Ikea and Home Depot both take fluorescent lamps for recycling around here, and Home Depot will also take ballasts--both for free. Of course, they would probably frown if you brought a whole case of lamps or a palate of ballasts in for recycling. Some local hardware stores are also jumping in on the bandwagon and offering lamp recycling.

I'm not sure if HID lamps are included...

I did not see that at the local HD. I'll have to check it out ASAP.

Twp I work in just shelled out >$500 for about 12-15 cs, mostly U-tubes and 4', all T12.

John., if you don't mind fill me in what is cs is cases ?

Merci,Marc

One of the plants I service here in Houston is in the business of disposing of HAZMAT waste. They have all sorts of separators and ovens they process waste. PCBs are burned there.

Apparently, these incinerators are some very heavy duty stuff, back in the early 90's we had a PCB amnesty here, I was reading at the time a book on how these PCB's are disposed of, the temperature that they incinerate these materials at, is something quite phenomenal.

We were sending a LOT of PCB filled gear (or the oil itself) to France.
Unfortunately, there are still a lot of devices here still in use here that contain PCB's and are only being found when they break down and have to be replaced (like fluorescent lighting ballasts).

We have a few of those old school trannys still working hard here in Hawthorne, CA. They are in rough-looking condition though. I'll try to get some pics for here soon.

The one shown in this thread has had an arc to the can, look to the left of the right-hand HV bushing. You may have to select the full size pic to see it clearly.

John,

In northern NJ my POCO still has some very old looking transformers on their poles. I wonder if they have been cleaned up.