Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Bangy on December 11, 2016, 09:28:17 pm
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Ive made it to AC chord wiring, and then testing, however I dont quite understand the Wiring for the AC chord.
AC chord--if I understand Dougs diagram the following is true:
Green - Ground - I get it ground to PT mounting Screw
Black - Fuse
White - To Primary from PT -HOW does this work? Do I simply use a wire nut and screw them togther, or?????
Primary (Black) PT 1 - ON/off - jumper other side of on/off to Fuse.
Primary #2 - to White from AC chord - How is this accomplished?
Thanks for the help. . .
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> White - To Primary from PT -HOW does this work? Do I simply use a wire nut and screw them togther
That's one way. Another is to have a well-insulated terminal to solder both to.
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... White - To Primary from PT -HOW does this work? Do I simply use a wire nut and screw them togther, or????? ...
I do one of 2 things:
1. Use a double-pole double-throw (DPDT) switch, which switches both hot and neutral on the power cord, or
2. Strip ends of White & PT primary, slide 2 sizes (one smaller, one larger) of heatshrink over one of the wires, twist, solder, position the heatshrink over the connection, and shrink to insulate.
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Thanks HBP and PRR
So am I understanding the DPDT switch will swap the hot and neutral wires even with a 3 prong connector????? If so I like that alot-- You never know how some of those old bars are wired. . .
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So am I understanding the DPDT switch will swap the hot and neutral wires even with a 3 prong connector????? If so I like that alot-- You never know how some of those old bars are wired. . .
That's not what HBP was suggesting. He was simply suggesting use a double pole switch to switch (not swap) hot and neutral. A DPST (4 lugs)would accomplish the same thing. His point was the double pole switch gives you a secure terminal to solder the neutral wire, giving an alternative to splicing the neutral to the PT wire with a wire nut.
Using a DPST switch as a 'line reverse' switch went out of style a long time ago.
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If you're not using an iec socket, but your ac cord directly goes through chassis, you should switch both active and neutral to meet european regulation.
Not sure if the same applies to USA, though...
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Understood. Thanks Sluckey. . . Bangy
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So am I understanding the DPDT switch will swap the hot and neutral wires even with a 3 prong connector????? If so I like that alot-- You never know how some of those old bars are wired. . .
That's not what HBP was suggesting. He was simply suggesting use a double pole switch to switch (not swap) hot and neutral. A DPST (4 lugs)would accomplish the same thing. His point was the double pole switch gives you a secure terminal to solder the neutral wire, giving an alternative to splicing the neutral to the PT wire with a wire nut.
Using a DPST switch as a 'line reverse' switch went out of style a long time ago.
Bangy,
If you are playing out at some old bar or wherever and are worried about reverse polarity (or worse) on the outlets, just pick up a cheap outlet tester at Home Depot or Lowes or any hardware store for that matter. If you find a bad outlet, stay away from it and notify the owner. That tester should be in your gig bag anyway, along with a good extension cord to get you to a GOOD outlet.
Jim
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If you're not using an iec socket, but your ac cord directly goes through chassis, you should switch both active and neutral to meet european regulation.
Not sure if the same applies to USA, though...
Does Europe require the ability to switch off both the hot and neutral if an IEC plug is installed?
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No, not 100% sure but IIRC with an IEC socket and detachable mains cable you don't even need to switch the hot if you don't want to.
Anyway, a power on switch usually comes handy, and switching the hot with a spst would be enough.
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I think the fuse must be after the switch too...