buck transformer

[Stunch]

I hooked up a filament transformer (Hammond 167U5) rated at: 115VAC primary, 5VAC secondary @ 15A and center tapped. The voltage at the wall was 122.5VAC, and after the transformer, 117VAC. Perfect, just what I wanted. But, what do I do with the centre tap in this configuration? Normally, you would attach it to chassis ground when used as a filament transformer, but in the meantime I have it capped off and not using it.

[DeathRex]

The center tap has AC on it, so you can't use it, except to cut 2.5 volts off the AC instead of 5.

15 amps is big, you only need it rated as much as the AC current in. Yours is big enough to run a hair dryer.

[Stunch]

Yeah, I oversized it because I'm going to run all my components off it, or just in case I use 2,000W mono blocks sometime in the future .... or dry my hair!

[Geek]

Lucky guy!

I used to have a nice, steady highish voltage like that.... then they installed smart meters and it's been 98-112V since!

[nyazzip]

then they installed smart meters and it's been 98-112V since!

really? those meters are coming here, soon...

[Geek]

Doesn't do it for evey one, just in rural areas. They call it "smart load balancing". Voltage is too low for the magnetron in the microwave to oscillate reliably. It's driving me nuts!

[Stunch]

We're on a smart meter here as well, in a very rural area. In the summer voltage is down to about 118-120.

[20to20]

We're on a smart meter here as well, in a very rural area. In the summer voltage is down to about 118-120.

We've had a "smart" meter for a few years now. The power company "pings" the meter for data every morning @9:30. It was tripping a GFCI breaker in my panel every morning because the circuit (bathroom) also feeds an adjacent room with my audio gear and one of the pieces has a line noise filter cap to the chassis ground. That was feeding the pulse out to the safety ground line bypassing the neutral and causing the damned breaker to trip. The ping is a 10Khz pulse for about 1 second. After about the first 20 trippings I realized it was happening every morning at the same time and called them to say someone on the line was spiking my voltage. They soon figured out it was them and their new meter polling system. But WHY was the question. I went through 100 hoops and chased bogus ideas about possible outlet/wiring soft shorts until I started isolating equipment on the line and finally figured it out. Power company changed the meter once for me after I bought another $40 GFCI breaker for to test for a bad breaker. Bottom line is the ping pulse is so strong it can cause weirdness... Now that mixer board stays on a 3 wire to 2 wire adapter socket.

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