After seeing so many recommendations on here, I'm going to build an isolation transformer. My original plans were to get two identical transformers out of microwaves, split them and use both the primary coils, but I have been foiled by transformers with identical part numbers having slightly different dimensions. So I'm planning on just wrapping the second coil myself. (Maybe I make two!)
I looked up the model number on the transformer, it's a ebj60664602 and is rated for 13A on the primary coil. No mention of a duty cycle though. Considering it's coming out of a homeowner microwave, I assume it's not rated for 100%. I don't forsee any of my applications really going over 6a, but I'm still going to try to future-proof myself as much as possible, by adding extra coils to the primary and a corresponding number to the secondary.
Here are some questions I have about this.
1. What temperature would you suggest for a themal fuse? I don't know the temp rating of the existing primary coil insulation, but it seems that the cheapest available (retail/ebay/digikey) is rated at 155C. Would 100C fuse be ok? Does anyone have an ideal location for placement?
2. I'm going to be doing some hand winding, so I can take muliple taps out of the secondary if needed. Would there be any use for this?
3. Does anyone have a preferred glue for putting core laminations back together? Some of the laminations split apart when I, uh, hit it with a small sledge. Repeatedly. Turns out this transformer doesn't have both halves welded together, the laminations are glued, then the two halves are pressed together along a u-shaped cut out in the seam. My plan is to glue the laminations with varnish or shellac (I have both) and then press the halves back into place on my hydraulic press. Would anyone suggest something different?
4. Would a fan be suggested? I have no idea how hot this will get in use.
Thanks!
I looked up the model number on the transformer, it's a ebj60664602 and is rated for 13A on the primary coil. No mention of a duty cycle though. Considering it's coming out of a homeowner microwave, I assume it's not rated for 100%. I don't forsee any of my applications really going over 6a, but I'm still going to try to future-proof myself as much as possible, by adding extra coils to the primary and a corresponding number to the secondary.
Here are some questions I have about this.
1. What temperature would you suggest for a themal fuse? I don't know the temp rating of the existing primary coil insulation, but it seems that the cheapest available (retail/ebay/digikey) is rated at 155C. Would 100C fuse be ok? Does anyone have an ideal location for placement?
2. I'm going to be doing some hand winding, so I can take muliple taps out of the secondary if needed. Would there be any use for this?
3. Does anyone have a preferred glue for putting core laminations back together? Some of the laminations split apart when I, uh, hit it with a small sledge. Repeatedly. Turns out this transformer doesn't have both halves welded together, the laminations are glued, then the two halves are pressed together along a u-shaped cut out in the seam. My plan is to glue the laminations with varnish or shellac (I have both) and then press the halves back into place on my hydraulic press. Would anyone suggest something different?
4. Would a fan be suggested? I have no idea how hot this will get in use.
Thanks!
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