WARNING!!!
This transformer is being offered for experimentation, custom designed projects or even just to get the large gauge enamelled windings!
The new owner ABSOLUTELY MUST KNOW WHAT THEY ARE DOING, THERE ARE LETHAL VOLTAGES/CURRENTS AT THE PRIMARY
THIS TRANSFORMER HAS BEEN WOUND FOR USE ON 115/230V SYSTEMS (2x 115V primaries in series)
THERE ARE NO INDICATIONS IT HAS BEEN SAFETY CERTIFIED FOR USE IN AUSTRALIA
I firmly believe in sustainability, wherever possible I try to encourage the reuse or repurposing of electronic/electrical components in particular - a LOT of energy* went into manufacturing these transformers and to send them to landfill seems such a tradegy because we are slowly poisoning our environment with masses of eWaste.
*Energy - more about the enormous amount of energy required to manufacture many electronic/electrical components and then their subsequent contribution to eWaste when buried in landfill will be on my site in the very near future.
The asking price for this transformer is only intended to cover my time in creating this advertisement.
HISTORY:
This transformer was used here in Australia in old stage lighting equipment. I suspect the equipment was originally sourced from the Asian region, probably Singapore. Fans were installed installed inside the very large spots to keep everything cool.
This stage lighting equipment was very large and heavy, dismantled due to obsolescence not a fault.
This transformer is physically very similar to the DT 8666's I have advertised separately but the primary and secondary voltages are slightly different to the DT 8666.
AC Stepdown Transformer
Country of manufacture is unknown
Manufacturer (stamped on the former) is MICHAEL
Part # DT 1238-1 EI120a-41,7L-Si
Paper label attached on top indicates:
2x separate 115V windings (primaries)
1x 23V @ 250VA (I think, the first number for the power rating is indistinct, its either a 2 or a 3!)
That's some pretty heafty current capabilitiy (roughly 10A but if I misread the label, possibly up to 15A) but the downside is the weight - this is VERY HEAVY @ 4.9Kg!
Dimensions: 110mm high x 120mm width x 100mm depth
Spade terminals for all connections
All terminals are numbered (see notes below about this numbering though)
COSMETIC CONDITION:
Not stored that well so the iron laminations show light rust to the top area, nothing too bad and certainly this will not affect operation of the transformer
All spade terminations are in great shape
Plastic former is not cracked or damaged
Core frame is a bolt on type and it is undamaged and with all bolts in place
TESTING:
Powered up via my Grundig Variac at 230V NOT 240V
Secondary voltage (open circuit) was measured as:
14 & 20 - 23.8V AC
Windings are all enamelled wire
Don't forget that when AC 230V is first applied, there is considerable primary "inrush" current for a very brief period of time, this is completely normal but it can trip your household circuit breakers. There is nothing wrong with the transformer, it is the "nature of the beast" with these high current AC transformers.
Actually looks to be a pretty good solid build, windings look "tight"
Standard E core using iron laminations
If the transformer doesn't suit your purposes, as long as the former can be removed without much effort, there will be plenty of enamelled wire for another project and "scrap metal" the rest of the transformer via recycling.
WINDING DESIGNATION NOTES:
The paper label on the top does NOT indicate which windings are which but it is pretty simple with this one -
2/3 - 5/6 115V
7/8 - 10/11 115V
18 - 20 23V (actually measured at 23.8V OC)
DC resistance measurements:
Terminals 2/3 - 5/6 2.9 Ohm
Terminals 7/8 - 10/11 2.9 Ohm
Terminals 18 - 20 0.5 Ohm
I applied the test 230V AC to terminals 2 & 8 but 6 & 7 must be shorted together so that the two primary coils are in series
THIS IS NOT AN AUTO TRANSFORMER - ELECTRICALLY THE PRIMARIES AND SECONDARIES ARE COMPLETELY, ELECTRICALLY ISOLATED. I ALSO MEGGER TESTED BETWEEN EACH "SIDE" OF THE TRANSFORMER AND TO THE LAMINATIONS - NO ISSUES HERE.
