Peerless S-217-D DIY

Dear CJ,

I have bisected the external can and all the stuff inside of the can following your advises!, but I want to know how I can to disamble  the lam core ??.....they look like fragile and I don't want to damage them !!

Opacheco

fantastic! been waitin to see that pic for about 100 years now! 

that core has wax between the lams which is stuck real good at room temp, so gently bake that thing at about 180 F or maybe 200 F if need be, and the lams should slide out, try not to bend them up as you can lose inductance,

can you do a quick inductance check? is there a good primary or are they booth cooked?

if not, connect a sig gen at 20 Hz maybe 10 volts and see how much current the coil draws,

can you take some more pics? like one from the sec side and maybe one from the top so we can see how shiny that core steel is?

thanks, you are the man!  maybe take DCR readings from good coils,  measure wire size with calipers,
shopped and cropped>

CJ said:

fantastic! been waitin to see that pic for about 100 years now! 

that core has wax between the lams which is stuck real good at room temp, so gently bake that thing at about 180 F or maybe 200 F if need be, and the lams should slide out, try not to bend them up as you can lose inductance,

can you do a quick inductance check? is there a good primary or are they booth cooked?

if not, connect a sig gen at 20 Hz maybe 10 volts and see how much current the coil draws,

can you take some more pics? like one from the sec side and maybe one from the top so we can see how shiny that core steel is?

thanks, you are the man!  maybe take DCR readings from good coils,  measure wire size with calipers,
shopped and cropped>

Click to expand...

Thanks CJ for your notes!

The two primaries are cooked, the terminals 2, 4 and 6 are cut, that is a shame....but I can see the 3 thin green terminals wires (# 36 AWG  you told me!) were cut in the limit of the paper bobin boundary....I will try to pull or unwind some wire in order to do the inductance measurement because I can't see a several damage in the two primaries winding itself.

I have a set of pics of all the bisection process in detail....a lot of them!!....I will try to take showing the shiny that core steel is.

I have baked the core severals times using aluminium foil in order to protect it. The wax is very difficult to drop until with bake process and the work is very difficult with but I have good result with the bake process in several steeps.

I will bake the core again in order to pull out the lams.



Thanks a lot again
Opacheco

shipping to USA is very high cost for a transformer like this...

Click to expand...

Huh?  It's an antique hunk of metal with absolutely zero tax value - according to whoever will be doing the looking - its a piece of salvage junk.

Can't think of anybody better for this job than CJ. 

oh i think he can do a good job, it is a pretty simple coil, no interleaving,

so just the order of the windings, P,  S and F/B to verify what we have already would be cool,

look at that shiny core,has to be  80% Ni,

you can do an inductance test on the secondary, we know the turns already, might drag down your generator a bit but all you need is about 1 volt, 20 Hz, maybe series the two secondaries in phase to get a more accurate reading as that way both coils are linking up ,

usually you can multiply sec Henries by the Z  ratio and get a pretty good idea of the pri inductance even thosugh there will be some error because you have less turns and therefore a bit more leakage, this also depends on their proximity to the core,

get out a Sharpie pen and mark the coils A and B so you can keep track of the lead breakout,

be sure to note start and finish leads and what color the leads are,


also insulation is just as important as the coil structure as it determines capacitance which determines freq response, calipers are handy for figuring thickness,

there might be some reverse winding on one or both coils so keep track of the coil rotation when unwinding,

before you take the core apart try filling out the rest of this lead chart>

here is a blub on the insulation, it was taken off a Peerless doc.

if you can fill in any details on what they mean by L and FP (probably means fiber paper) and how many pieces and what size then that would be over the top!

also, if you have some calipers, measure the outside thickness of the coil as you take the layers off,
this tells us the "build" or the dimensions of the coil as wire, tape, copper and insulation are added.

this also tells us how tight they are winding the coil (wire tension settings)

CJ,

Let me to check all these information and I will post soon!

Very interesting notes about the Secondaries Inductance y the Primaries Inductance Relation, all that inferred  from the secondaries inductance measurements values...I think this is treated like Impedance Reflection using the Impedance Ratio?

Thanks again!
Opacheco

yes, since inductance is turns squared, and impedance is turns squared, the ratio for one is the ratio for the other, in an ideal world.

you do not have to take each lamination apart one at a time, you can simply heat up the transformer and pull the coils apart, the core should split in half because those are L lams.

then you can pull the lams out of the coil, try not to bend them as you break the crystals and the permeability goes down.

CJ said:

yes, since inductance is turns squared, and impedance is turns squared, the ratio for one is the ratio for the other, in an ideal world.

you do not have to take each lamination apart one at a time, you can simply heat up the transformer and pull the coils apart, the core should split in half because those are L lams.

then you can pull the lams out of the coil, try not to bend them as you break the crystals and the permeability goes down.

Click to expand...

Oh man!, fantastic!...I did wanted to ask you that but my English is not to good: The idea is to Take Apart one Stack Leg in one piece of each Coil first, am I right?....then pull the lams out.

The Z1/ Z2 = L1/L2   

Therefore,

L1 = (Z1/Z2)*L2

Nice analysis!

Thanks for your advise!
Opacheco.

just a thought, look for pins in the lam holes, sometimes they stick wood or metal pins in there to hold the core together,

CJ said:

just a thought, look for pins in the lam holes, sometimes they stick wood or metal pins in there to hold the core together,

Click to expand...

Nice idea in order to pull all the lams at once you mean?.....Let me to try.

Opacheco.

check the holes in the core stack for pins by pushing a 1/2  watt resistor lead to verify that the holes are clear before you try to pull the core apart,

CJ said:

check the holes in the core stack for pins by pushing a 1/2  watt resistor lead to verify that the holes are clear before you try to pull the core apart,

Click to expand...

Ok....although they look like very, very clean inside, I can see the light thru of them and they don't have any obstruction at all.

Opacheco.

opacheco said:

Ok....although they look like very, very clean inside, I can see the light thru of them and they don't have any obstruction at all.

Opacheco.

Click to expand...

Hi Opacheco, I tried to PM you regarding  S-217D but your box is full. Can you please contact me by mail?  (please find it inside my signature)