HISTORY:
Imported from an international research laboratory (by ship!) as the equipment was being disposed of due to the previous establishment upgrading their equipment in the early 2000's. This is yet another very nice item of industrial equipment which I have decided will become an organ donor.
It is the MATSUNAGA (Yokohama Japan) Frequency Converter, intended for laboratory use and providing up to 240V AC at a user adjustable variable frequency. Not only that, the AC voltage output could be varied across a wide range AND the user could set current limiting, so it could alter all three aspects of the AC output wavefrom, frequency, voltage and current limiting. I actually fired this gear up and it was working great but oh dear! What to do with it? Sure you could put up on the workbench but at that sort of weight it needed a lot of space and a good solid workbench. I decided a while back to offer this equipment as a complete unit "elsewhere" online for a while but there was no interest at all so I pondered over what to do with this equipment (to keep or not to keep) but it had a few things going against it.
As a complete unit it was EXTREMELY HEAVY, over 50Kg, which means that my arms are now 30cm longer from lugging this beast around the workshops! ... but more seriously, shipping would have been difficult to ensure safe travel AND very expensive. It also had other minor cosmetic issues because it is not easy moving such a monster around so it suffered scrap marks on various places of the all steel casing.
So, the "donor operation" has begun and here is yet another inductor from the equipment .... a small iron core choke
The component manufacturer, Haruna-Denki (Tokyo Japan) began operations in 1981 and remain active in the design & manufacture of generator sets, transformers, high power equipment etc
UNIDENTIFIED (Japan) - High Current Low Inductance Choke
Made in Japan
Circa late 1990's
Inductance: 100uH
Voltage: up to 250V AC in the original equipment
Current capability: 30A (!)
Part # CH-0501
Identification (top side printed) markings:
CH-0501
100uH - 30A
Identification (vertically printed down one side of the frame)
H-8-11
Nowhere is the manufacturers name printed on the choke but I am 99% sure this is another HARUNA-DENKI (Japan) product, supplier of it's much larger "brother" HERE
DIMENSIONS:
Body is 43mm width x 35mm height x 35mm depth
The 'stiff' (large diameter copper wire) flying leads are just 35mm in length and terminated with eye screw connectors.
WEIGHT:
200g
COSMETIC CONDITION:
USED (but you wouldn't know it!)
CLEAN (like new!)
No signs of any winding stress at all
Windings and frame are all TIGHT and SECURE
TESTING:
Being a previously installed and old component, I took a look at the inductance and resistance
Inductance: 10uH
DC Resistance: 0.7 Ohm
While my basic LCR test equipment these days is pretty limited, I am surprised at this reading which is way below what was expected. I double checked the stated value on the choke and it definitely indicates 100uH I am beginning to doubt my inductance tester as the much large choke measurement was also "out" and yet I know these components were performing their tasks while installed in the equipment previously.
It would be a good idea for the new owner to double check the inductance of this choke prior to use!
I have now protected this choke with bubble-wrap and sealed it within clear plastic packaging, awaiting installation in that super you-beaut power supply you have always dreamed of creating!
