POLL: Fun with bias/voltage meters? What is your wall voltage?

[Cal Blacksmith]

I done went to coleage to lirn aboutin this elict.... eliac... elecr... thatn stuff in the wars an i's bean dooin mys owwn werk forin a while.

but seriously, it is rare to have a house wired in the 50s with anything more than 14 ga wire which should be fused at 15amps. My house which was made in the late 70s only had a 100 amp service and was mostly wired with 14 gauge wire. I have since upgraded to a 200 amp pannel and added a shop building that I ran 100 amps to, though it is wired for 160 amps. There is a problem in your house if it has so many 30 amp fuses. Fuses are fine though most homes of the 40s and 50s were only fed into 60 amp services. They had little else than lights to run and perhaps an old Philco radio. Modern demands are MUCH higher.

I agree that you should use a local electrican to survey the situation as without getting in the box and looking at what you have, everyone is just guessing and I would not stake the safety of your home on a guess. If you do indeed have conduit in the walls, (wire run through pipes) the upgrade situation is much easier than in modern construction where Romex is used.

[meagain]

Unless the wire lists a guage on it (close to the outlet & visible), I likely wouldn't be able to judge what gauge it is visually unless I can compare it to traditional Monster wire.

Allan - I asked a few questions above about your 200 amp service ramp up... Mostly, did they have to run a crazy thick mega wire from the pole underground to your house, etc? I'm thinking that's how it works given us getting an insane estimate of many thousands. Is that how that went for you?

I think the general consensus for me with my electrical is that the previous owners likely used bigger fuses perhaps to avoid fuse blows and we just parroted it. And if true, my wires, etc. could be running hotter, etc. than they should and it's not a healthy situation. Still, some of these rooms aren't even used except for an occasional lamp. I'm going to try to sort this out as best I can before electrician visits. But my main concern is the listening room so for kicks, I'll put a 15a on it and try to sort out what 'type' fuse I need. Type 'S', etc. etc. cuz perhaps the type of fuse is wrong also. IDK. I think adding up my wattage, the 15a would be fine.

[Allan Songer]

Yeah--they ran a new service from the pole in the alley behind my house into new 2" conduit that runs down the side of the house from the second story to the new breaker box. I did this upgrade as part of a complete kitchen remodel that ended up at about 90 grand for the whole project ( a horrible 7 months!), so I don't remember EXACTLY what the electrical work cost me (rewire entire downstairs and one cirucuit upstairs, new 200 amp service), but I think is was something like 6 grand all in. This was 6-7 years ago.

[meagain]

Yipes.

OK - Let's see if I have this right.... If I'm running a 20a fuse on a circuit with the room wired guage-wise for a 15a (even if wattage hooked to it is fine with 15a).... the fuses act like a surge protector to prevent the wires from frying? And using 20a instead of 15a allows more juice thru..... then more oomph is running through the outlet wires (IF I'm overloaded at 15a?) which might be too much for the amps? And I wonder that these little spikes/surges that are undetectable when the meter is hooked up, might be over the 15a and causing an issue I can't see? And bonus points for my avg wall numbers coming in at 124-125ish (this is a new average cuz I think the power co. gave us more oomph lately). OK - heading out to buy 15a fuses.....

(My money is still on the "the tube pin holes had oxidation" theory. Makes a ton of sense to me). []

[sfogg]

"If I'm running a 20a fuse on a circuit with the room wired guage-wise for a 15a (even if wattage hooked to it is fine with 15a).... the fuses act like a surge protector to prevent the wires from frying?"

The fuse is not a surge protector. It is an overload protector. If more then 20a flows through the fuse (for more then a short amount of time) the fuse blows. In your case if the wires can only handle 15a (or less) and you have fuses rated for higher then that potentially the wires will burn up before the fuse. That is where an electrical fire can start.

"And using 20a instead of 15a allows more juice thru..... then more oomph is running through the outlet wires (IF I'm overloaded at 15a?) which might be too much for the amps?"

No, the amps will pull the current they need assuming their is sufficient current available. Having them on a 20 amp circuit will not hurt them at all.

Shawn

[Deang]

This ended up being a really good thread. Lisa may drive everyone nuts but the threads always end up with a lot of good information in them. I've seen enough here that tells me I need to get an electrician out to my house.

[mark1101]

Wow, yet another thread on another problem Lisa has. If it isn't amps, tweeters, woofers, out of phase speakers, ugly looking speakers, color, end bell caps, crossovers, tubes, fuses, decisions, graphic equalizers, or microphones, walls, room dimensions, and ambient noise floors, then it must be bills, Tuesday, and electrical problems. And people rush in to help.

.......excuse me......you forgot remote controls and pet food.......carry on. []

Edit: Oops, also forgot gutters and foundation cracks.

[anarchist]

Lisa,

Some of us "forum members" have actually wired a house so we aren't just throwing out "subjective" opinions about electricity.

Let me make it simple... and you don't need to pay an electrician to tell you this. EVERY homeowner should understand these basic principles and be able perform simple diagnostics. If they can't... they have more money than sense.

The fuse, the wire, and the outlet are a system. They should all match. If you have 30AMP fuses on 12 gauge or 14 gauge wire, that fuse will allow your wire to pull more than the 15 or 20 amps it is rated for resulting in the wire heating up, burning its sheathing, and placing you at risk of fire.

The wire is marked with its gauge. If not visible when removing the outlet, you can discern the gauge by look (if experienced) or use a wire cutter/stripper to determine the size. There is little doubt you are going to find you don't have the house wired with 10 gauge wire throughout and those 30amp fuses are a problem.

When you rectify the fuse situation, I would not be surprised to find you recognizing you are starting to blow a few fuses - hence the reason someone placed 30 amp fuses in that fuse box. This is the a$$hole approach to fixing the problem. The electricians approach will be to evaluate and modify the circuits so the load is balanced across the circuits.

Now for an electrician...

... you likely have a less than optimal grounding system and should upgrade it to reduce the damage spikes could cause - they want to go to ground but follow the path of least resistance (meaning your equipment if your ground sucks.) This isn't a big deal either - stick a grounding rod in the ground, place a ground clamp on it, wire it to the existing ground or directly to the fuse block.

... make certain you have a dedicated circuit for those water pumps - outdoor outlet - and it is not simply cascaded off an existing circuit particularly if you are feeding two rooms with massive amounts of electronic equipment in them.

... the NEC provides more than a few rules on electrical wiring and lays out the law on how many devices can be installed on a particular circuit and what devices require their own circuit and exactly how many amps particular circuits should be and what outlets are used.

Another example to give you a few ideas. 20AMP circuit - meaning 20 amp circuit breaker, 12 gauge wire. Stick something as simple as a microwave and a "George Foreman" grill on there, operate them simultaneously and you can quickly pop the circuit breaker. Stick 2 water bucket heaters on a 20amp circuit with 12 gauge wire and a proper fuse... and you will be replacing fuses all day until you decide to only use 1 water bucket heater.

Now, how much stuff do you have running in those two rooms and outside on that 1 circuit?

These are separate issues though - one is safety and the other is your amplifiers.

[dtel]

The reason for the fuse or breaker to match the wire gauge is very simple.

If you put a 30 amp fuse or breaker on a #14 wire and draw a large amount of current, or have a short the whole wire will glow red hot and melt the insulation and start a fire (before) the fuse or breaker would blow or trip

Just the opposite of the way it is designed.

[flannj]

Lisa, Some of us "forum members" have actually wired a house so we aren't just throwing out "subjective" opinions about electricity.

Let me make it simple... and you don't need to pay an electrician to tell you this. EVERY homeowner should understand these basic principles and be able perform simple diagnostics. If they can't... they have more money than sense.

The fuse, the wire, and the outlet are a system. They should all match. If you have 30AMP fuses on 12 gauge or 14 gauge wire, that fuse will allow your wire to pull more than the 15 or 20 amps it is rated for resulting in the wire heating up, burning its sheathing, and placing you at risk of fire.

The wire is marked with its gauge. If not visible when removing the outlet, you can discern the gauge by look (if experienced) or use a wire cutter/stripper to determine the size. There is little doubt you are going to find you don't have the house wired with 10 gauge wire throughout and those 30amp fuses are a problem.

When you rectify the fuse situation, I would not be surprised to find you recognizing you are starting to blow a few fuses - hence the reason someone placed 30 amp fuses in that fuse box. This is the a$$hole approach to fixing the problem. The electricians approach will be to evaluate and modify the circuits so the load is balanced across the circuits.

Now for an electrician...

... you likely have a less than optimal grounding system and should upgrade it to reduce the damage spikes could cause - they want to go to ground but follow the path of least resistance (meaning your equipment if your ground sucks.) This isn't a big deal either - stick a grounding rod in the ground, place a ground clamp on it, wire it to the existing ground or directly to the fuse block.

... make certain you have a dedicated circuit for those water pumps - outdoor outlet - and it is not simply cascaded off an existing circuit particularly if you are feeding two rooms with massive amounts of electronic equipment in them.

... the NEC provides more than a few rules on electrical wiring and lays out the law on how many devices can be installed on a particular circuit and what devices require their own circuit and exactly how many amps particular circuits should be and what outlets are used.

Another example to give you a few ideas. 20AMP circuit - meaning 20 amp circuit breaker, 12 gauge wire. Stick something as simple as a microwave and a "George Foreman" grill on there, operate them simultaneously and you can quickly pop the circuit breaker. Stick 2 water bucket heaters on a 20amp circuit with 12 gauge wire and a proper fuse... and you will be replacing fuses all day until you decide to only use 1 water bucket heater.

Now, how much stuff do you have running in those two rooms and outside on that 1 circuit?

These are separate issues though - one is safety and the other is your amplifiers.

All good advice Anarchist, and what do you want to bet there is no GFCI on that circuit either.

- Jim

[Arky]

This ended up being a really good thread. Lisa may drive everyone nuts but the threads always end up with a lot of good information in them. I've seen enough here that tells me I need to get an electrician out to my house.

Good observation. Typical of a lot of "hijacked" threads on this board, lots of good information revealed, even if off original topic.

[meagain]

One outlet wire says "type tw" There's a number in front of this but it's really hard to make out. If I had to guess, I'd say 14. But not sure. But in the other room, well, that outlet is complicated. This indoor outlet is on the other side of the outdoor outlet. I see 2 screw on caps that hold 4 wires each. There is thicker wire here, but thin also. Maybe this thicker wire is why I have a 20 amp fuse running it?

[NOSValves]

Allot of good information in this thread for sure. The problem is just fixing any problem her electrical may have is not the only problem present causing the amp problems. If fact if the circuit with the audio equipment on it is fix the wall voltage is going to rise! It will be more stable but most likely will rise to 127V like the rest of her home.

The issues as I categorize them.

1) Heavy usage at higher the spec wall voltage is #1 issue here. If you log 5000 hours a year on a pair of VRD's and your wall voltage is 125 and you bias them to .70 VDC YOU ARE GOING TO BURN THROUGH TUBES. I could careless what brand they are. I bet in this case its more like 7000 hours maybe more in a year. Just about all the major brand tube equipment manuals for higher powered tubes amps recommend output tube replacement every 3000 hours of usage. Under normal conditions that would equate to every 2 years!!

2) If you have questionable wall current/voltage stability which is pretty obvious in this case it's not going to be kind to tubes in the amplifier running near the ragged edge of specification. The pumps causing a 3 to 4 volt drop in wall voltage proves an absolute issue with current/voltage stability and this is without the VRD's and tube equipment running in the picture !! The amps are here folks....so the 280 watts the pair amps pull at idle is not on this circuit right now.

3) oxidized pins is another issue but I would call it the least of the problem here. Oxidized pins cause tube runaway and she never experienced that. She did experience unstable bias even with fresh brand new tubes and also this flickering light syndrome. The light runs directly off the AC Wall voltage and has nothing to do with the amplifiers inner electrical workings. The light is completely stable here....Speculate on that.

I think that for this pair of amps to be working perfectly here is a testament to the reliability of the amplifiers. Tubes are consumables!! They have a life span the more and harder you run them the lower that life span will be.

In my opinion even with the electrical issues repaired a Furman or similar device is in order. I offered to modify the amps a bit to make then less finicky to her usage style but she has refused that option. You can't have your cake and eat it too.

Craig

[homemadeheresy]

122.8

[Deang]

I offered to modify the amps a bit to make then less finicky to her usage style but she has refused that option.

You offered to put the soft start circuit in them and she turned you down? LISA!!!???

[anarchist]

That wire on the outside is almost certainly 12 gauge so the interior wiring is 14 gauge meaning a 15 amp circuit. Another stupid thing to do - you are supposed to match the wiring. The 14 gauge is your limiting factor and just because someone spliced in 20 gauge doesn't mean you can place a 20amp fuse in the circuit. Bottom line is you have about 1440 watts you can place on that circuit before you violate code restrictions and jeopardize safety.

Craig just provided the wattage of those amps at idle. Add your pumps, your computer, the monitor, the HK, the lights, and anything else plugged into that circuit and see where you are at. Remember those numbers are at idle. Now, if you are running at the limits of that circuit, and you have pumps flipping on and off... you are going to have spikes and sudden current drops.

Two screw on caps. 4 wires each... you are wired with two wires - a hot and a neutral. No additional ground. Leading me back to my previous statement about the grounding. Additionally, depending on the size of the box these wires are in, you may have exceeded the box capacity. 8 conductors plus 2 clamps plus the wall outlet...11 conductors... that should be a 1.5 by 4 11/16 box or larger.

[sfogg]

"Two screw on caps. 4 wires each... you are wired with two wires - a
hot and a neutral. No additional ground. Leading me back to my
previous statement about the grounding. "

Good catch. And if she doesn't have a ground her surge protectors will not work.

Shawn

[meagain]

Pumps cause a 3-4 volt drop in wall voltage? How did we go from 1 to 1.2ish to 3-4?

The only thing I want to know is why fuses/tubes blow somewhere between off/on. Every time except the last time (surely due to a kt88 being old), it's been with off/on. If that's due to my electrical, then I need to figure out what it is. Not trying to be confrontational, just try to figure it out.

280w at idle? How could I figure out what they're doing with TV or Music?

DEAN - Soft start wasn't vetoed 100%. Mostly I was just ticked off and told Craig to bill me and send them back. My ONLY concern with soft-start option is that it goes beyond soft start and runs at 1-2 volts lower. I'm concerned about this cuz if I get a volt regulator that lowers the volts to the amps, I'm lowering it again with soft-start. IDK, I'm sure it's fine - I just wanted to learn more about it and it's relation to any gadget I have to buy.

I just wish for them to work out for me here cuz I was really likeing the sound I've been getting recently.

[mark1101]

Allot of good information in this thread for sure. The problem is just fixing any problem her electrical may have is not the only problem present causing the amp problems. If fact if the circuit with the audio equipment on it is fix the wall voltage is going to rise! It will be more stable but most likely will rise to 127V like the rest of her home.

The issues as I categorize them.

1) Heavy usage at higher the spec wall voltage is #1 issue here. If you log 5000 hours a year on a pair of VRD's and your wall voltage is 125 and you bias them to .70 VDC YOU ARE GOING TO BURN THROUGH TUBES. I could careless what brand they are. I bet in this case its more like 7000 hours maybe more in a year. Just about all the major brand tube equipment manuals for higher powered tubes amps recommend output tube replacement every 3000 hours of usage. Under normal conditions that would equate to every 2 years!!

2) If you have questionable wall current/voltage stability which is pretty obvious in this case it's not going to be kind to tubes in the amplifier running near the ragged edge of specification. The pumps causing a 3 to 4 volt drop in wall voltage proves an absolute issue with current/voltage stability and this is without the VRD's and tube equipment running in the picture !! The amps are here folks....so the 280 watts the pair amps pull at idle is not on this circuit right now.

3) oxidized pins is another issue but I would call it the least of the problem here. Oxidized pins cause tube runaway and she never experienced that. She did experience unstable bias even with fresh brand new tubes and also this flickering light syndrome. The light runs directly off the AC Wall voltage and has nothing to do with the amplifiers inner electrical workings. The light is completely stable here....Speculate on that.

I think that for this pair of amps to be working perfectly here is a testament to the reliability of the amplifiers. Tubes are consumables!! They have a life span the more and harder you run them the lower that life span will be.

In my opinion even with the electrical issues repaired a Furman or similar device is in order. I offered to modify the amps a bit to make then less finicky to her usage style but she has refused that option. You can't have your cake and eat it too.

Craig

Craig,

What would be handy for us VRD customers is a handy dandy cross reference matrix that recommends a bias spec for a particular wall voltage to help maximize tube life and/or achieve a specific performance. This could be as simple as a small spreadsheet and I volunteer to create it if you send me some numbers.

For instance: my wall voltage is 121-124. Those are the approximate extremes I see. I always bias around .72 and God only knows the wall voltage when I get around to making adjustments. Is .72 correct for 121v, 122v, 123v, and 124v too? This is type of info I'd be interested in.

If you think it is of value then let's discuss some numbers and I'll produce a spreadsheet to circulate.

[NOSValves]

I believe that she does have a ground of some sort I had her check the polarity of the one outlet from ground to hot and common and she did get readings.