Greetings fellows, I have a pretty hefty transformer I pulled from an older amp that has 10 outputs on it. A set of 7 and then a set of three. Whats the best way to figure out whats what on it? Some of the outputs have green resistors on them.
Runs on 110v obviously, I have it plugged in, getting different voltages between the 10 outputs, but not sure which ones to link up. I will be running multiple voltage regulators, so I want to take advantage of the multiple outputs.
Tag on it reads
88-NFT-621-01
75J033HD
TAM TH 9834
Any advice would be appreciated. Thanks in advance
Take a piece of paper, measure the continuity between all connectors and draw it. Then measure voltages between all connectors and figure out what you have
Please keep in mind you measure the continuity with the power removed, the hard part is determining the power ability of each output, you can use dummy loads to get an idea of it.
The green "resistors" on the little board are each marked 7AMP 125v or 10AMP 125 volt. I will only be using 1AMP voltage regulators per two wires. Am I pretty safe to pick any two wires that have an acceptable voltage and use them? The readings are around
15
30
45
even 60 volts
You need to show pictures, transformers don't have components on them, what you have is a compound device, probably a transformer with rectifiers and/or protection devices on the PCB.
You are not safe to do anything until what you're posting makes sense. Again I say please post some decent quality photo's.
The green "resistors" on the little board are each marked 7AMP 125v or 10AMP 125 volt. I will only be using 1AMP voltage regulators per two wires. Am I pretty safe to pick any two wires that have an acceptable voltage and use them? The readings are around
15
30
45
even 60 volts
I would imagine the highest voltage you'll get is between the outermost of the 10 pins. What would be nice to know is if this transformer is centerpoint-grounded or endpoint-grounded. You might try testing continuity between each of the output pins and the transformer core. Some transformers will measure little to no resistance between the core and one of the pins. That pin will be your ground.
Being it was inan audio amplifier the 30 volt tap as you refer to it is probibly the center ground or common point with +- 15 and 30 volt pairs of rails going out from that.
if it came out of a receiver, most of the secondaries are going to be center tapped. most amplifiers and receivers use bipolar supplies, so the secondaries for the output stage supply and the preamp circuit supplies will be center tapped. you may have one 12V non-center tapped supply for logic and relays. one or more of the pins on the transformer could be non-connected...
this looks like a dual voltage center tapped secondary for +/-30, and +/-15. the pin you marked as "30" is actually the center tap, the "15" and "45" pins are 15V, and the "0" (whichever end you used as common) and "60" pins are the 30V outputs. this leaves 5 pins unaccounted for, and they may be another center tapped winding and a non-center tapped winding, or another dual voltage winding.
First set of three are
Pin 1 -7amp
Pin 2 -center tap (I assume)
Pin 3 -7amp
Then the set of 7
Pin 4 - appears to be connected to pin 10 internally
Pin 5 -10amp
Pin 6 -10amp
Pin 7 -Would appear to be center tap for Pins 5,6,8,9
Pin 8 -10amp
Pin 9 -10amp
pin 10 -seems to be connected to pin 4 internally
I'll use pins 5 through 10 and use pin -7 as my ground.
First set of three are
Pin 1 -7amp
Pin 2 -center tap (I assume)
Pin 3 -7amp
Then the set of 7
Pin 4 - appears to be connected to pin 10 internally
Pin 5 -10amp
Pin 6 -10amp
Pin 7 -Would appear to be center tap for Pins 5,6,8,9
Pin 8 -10amp
Pin 9 -10amp
pin 10 -seems to be connected to pin 4 internally
I'll use pins 5 through 10 and use pin -7 as my ground.
ok, 4 and 10 arent connected as I thought. Heres what I'm getting
Pins 1-3 are a set of their own.
Pins 4 through 10 are a set with 7 as the common or middle.
Between 7 and pins 4, 10, I get 20v
Between 7 and pins 5, 9 I get 30v
Between 7 and pins 6, 8 I get 15v
Its just that pins 4 and 10 arent fused on the board.
Please be aware that the fuse ratings are the fault limits of the transformer. Not how much current you can expect to draw from them continuously. I would not plan to draw more than 50% of those numbers. Also remember that once you go through a rectifier and into your filter caps, that the voltage will be about 40% higher than the AC voltage. So you need to further reduce your load current. Please read the discussion in the following thread. https://www.electro-tech-online.com/threads/power-supply-questions.127780/
Your "unconnected" pins could to to the copper electrostsic band on the xformer.
Sorta sounds like a transformer for an amp that has multiple rails depending on the power level. Those amps are tough to troubleshoot. I only saw one of them.