I am looking for some help identifying two wires on a power transformer.
I have the power transformer from an Art Audio Gill Signature amplifier that is marked CT-9074 & MS 1-45. The primaries are black & black/white stripe. The transformer also has a white and a gray wire and I am unsure what they are.
I know what all the other wire colors are except these two.
Anyone familiar with this color code? Dual primaries possibly?
Any help would be appreciated
I have the power transformer from an Art Audio Gill Signature amplifier that is marked CT-9074 & MS 1-45. The primaries are black & black/white stripe. The transformer also has a white and a gray wire and I am unsure what they are.
I know what all the other wire colors are except these two.
Anyone familiar with this color code? Dual primaries possibly?
Any help would be appreciated
First check for continuity to any of the other windings. White/gray could be another winding,
a shield, etc. You can apply line to the known primary and check for voltage on the white/gray.
If it's the same voltage as the AC line, it could be a dual primary. How was it originally wired?
a shield, etc. You can apply line to the known primary and check for voltage on the white/gray.
If it's the same voltage as the AC line, it could be a dual primary. How was it originally wired?
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Thank you for the information.
They have continuity with each other but not to the black wires. I will check if they have continuity with any other leads and post the results.
They have continuity with each other but not to the black wires. I will check if they have continuity with any other leads and post the results.
I just checked and the gray and white do not have continuity with any other leads besides themselves and have the same gauge wire as the primaries.
If the resistance is similar for two windings, they may both be primaries. The resistance will depend on the VA rating of the transformer. Here's where it gets interesting... polarity of both windings must be the same to connect them in series (230V) or parallel (115V). Consider it like a battery, with + and - ends. You can connect them in series, connect 120V to ONE primary, and measure the voltage across both. If it's 240V, they are connected + to -. To connect in parallel, they must be connected + to + and - to -.
You can run a 60Hz sine generator at 10V or so into the primary winding, and check the gray/white voltage
to see if it is at about the same amplitude. If so, it probably is a dual primary transformer. Use this
opportunity to properly phase these two windings on the scope, if you intend to parallel them.