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conversion from 120v to 220v sansui au d33 amplifier

hello to everybody

I have a sansui au d33 amplifier , on the back is stated input 110 120 220 240 v

there's asticker 120v and it's working in 120v , I would like to have it working in 220v as it's in Italy , inside on the board ( F3579 page 8 of the service manual ) where's the fuse there are pin connectors that I think should be changed in the correct position for the differet input but I haven't figured out how , even in the service manual there's no explanation about it

if I connect to the 220v now the fuse 2A blows immediately as it draws more current ( for 110 v is advised 5A fuse )

anybody familiar with Sansui's way of label board connections ? can explain how to change the pins ?

tomorrow I' ll try to post a picture of the board with the cables connected as they are now , how can I upload a picture ?

of the total 5 wires ( blue orange yellow purple red ) with pins (on the board 7 total pin posts so 2 are free ):

there are the blue orange and yellow wire pins positioned as I understand for 120v position marked on the board

what does spare TM mean (there are purple and red cable pins connected there) ?

the area next to spare tm ( next to the printed words "yellow orange ") has two pin posts but no wires attached , should I connect one there ? these are the only free pin posts , everything else on the board is soldered

Would be correct to move purple from spare tm to one of the free posts as to complete the 220v connections advised ont he board ?

many thanks

conversion from 120v to 220v sansui au d33 amplifier

look on the back panel or the bottom of the unit for a recessed switch that says "120v" then try moving it to the 220 position

conversion from 120v to 220v sansui au d33 amplifier

there's no swich for the voltage change not even in the inside of machine , as i understood the circuit I have to move the pins but can't understand well the writings on the board

conversion from 120v to 220v sansui au d33 amplifier

VERY important to notice this:
There is five different versions of this AMPs power transformer.

But genereally you can follow this:

Neutral power should be cennected to the BROWN wire on the transformer.
Live power should be connected to the PURPLE OR BLUE wire on transformer. (Blue for 220V, Purple for 240V)

If the transformer is equipped with 6 wires at the primary, they should be of the following colours:
Brown, Red, Orange Yellow, Blue and Purple.

Then the Live power should be connected to the Brown wire, The Red wire should be connected to the Yellow wire, and finally: The purple wire to Neutral power. (For 240V operation)

For 220V operation connect the Neutral power to the Blue wire instead of the purple.

Tace good care insulating the wires wich is not soldered to the PCB.

conversion from 120v to 220v sansui au d33 amplifier

thanks for the explanation , if you can post also the wire connections for the 120 version I'll try to figure out the function of the cables , there are many wires coming out of the transformer on both sides up and down , it's not very simple , there are all the 6 colors you mentioned plus more ,

on the machine there is no identification for the version EU USA or so on , only it's labeled input 100 120 220 240 , there's a sticker 120 so I think the machnie is multivoltage and they put the correct sticker after connecting the pins in the chosen way

I' ll ask a friend who's more familiar than me with circuit schemes if he can help

many thanks

conversion from 120v to 220v sansui au d33 amplifier

For 120V operation You should connect together the following:

Yellow and Brown. Connectede to Live

Orange and Blue, connected to Neutral.

Insulate all others.

There is only one wire I unfortunately haven't control of: The one for the thermofuse in the transformer.
This thermofuse should be in series with the Live wiring.
It seems as if it is internally connected to the Brown wire
In the versions with 100V/120V, and the versions with 220V/240V this thermofuse is internally in series with this brown wire.

If Yot have an additional wire on the primary side of the transformer, it's lightly that one wich is the thermo fuse. If so, the Live input should be connected to that wire, and then the Brown and Yellow leads only connected together. ONLY for 120V operation.

For 220V/240V operation the live wire should bbe connected to this additional wire, and then just as I described in my last reply

conversion from 120v to 220v sansui au d33 amplifier

hello and thanks to everybody

with the help of tandbergeren advices I figured out the connections and I' m listening now to the sansui connected to the notebook

this model I have is the multivoltage ,

so now is working at 240 v wiring

correction : orange and yellow in series ( in the posts that were free before )

and if I have understood it well :

blue at live (in the serial post where before was also orange )

purple and red on spare t m posts ( not used I think )

thermocouple wire is white and is soldered originally by sansui on the posts with brown and a yellow neutral coming directly from inlet cable ( which is not the same yellow in series with orange )


hopefully this 'll help someone else to make similar mods