Central Vac overload

Exactly correct. Very odd to see, but about 4A less when screaming like a rocket.

-- Bobby G.

I said that backwards. The RPM does decrease when the motor is overloaded but the key to that is a blocked hose isn't really a motor overload.

The irony/complicating factor is that the motor will thermally overload eventually due to the blocked air flow but not from being asked to do more work than it can handle. It's doing less work than normal (4 amps less on the Kill-o-watt meter) but it's not getting proper cooling anymore.

Thanks!

-- Bobby G.

Unfortunately my server delivers posts in frighteningly non-chrono order and I reply the same way. I *do* get it now and realize why my portable submersible pump makes the same kind of increased noise when it starts running dry. It takes a lot less power to raise air ten feet than water.

Live and learn . . . eventually. Then go senile and repeat.

-- Bobby G.

Good point. In a home automation controller progam that could likely be solved by taking action only if the amperage drop persisted for over three seconds. There are times when a vacuum will suck in the end of a drape or something large enough to block the tube obviously but temporarily. I think it might be helpful to have Art's valve working in those cases because the relief would open up and whatever was stuck would just fall away.

Considering how complicated this little exercise has become, it makes me wonder what's really going on in Toyota's fly-by-wire system and whether they truly did cover all the potential "exceptions" that might occur. We may never know now that every scam artist who happens to own or have access to a Toyota is looking for a quick buck or a new car by claiming "runaway."

Thanks for your input, Ian.

-- Bobby G.

You may find the current doesn't drop significantly as the power consumprion does.

When load is removed from sysncronous motors the power factor decreses to the bottom, the current stays relatively in the same ball park, depending on motor design.

If you put a Kill-a-Watt monitor on it you may a huge difference in consumption.

Exactly correct. Very odd to see, but about 4A less when screaming like a rocket.

-- Bobby G.

I always figured it has something to do with ionic chrage passing air over an aluminum exchanger.

It may be just drying the air too much or some kind of ion charge or both.

One reason we got the central vac is that we like to air cool in the summer with a big attic fan and that brings in an awful lot of dust and pollen. Switching from A/C to "free air" cooling cured my wife's allergy. Turns out that being cloistered inside superclean, highly filtered office and A/C house hyper-sensitized her to pollen. She used to sneeze up to nine times when she left an A/C'ed building and stepped out into the late spring air, which *is* mostly pollen. Our standing joke is "we don't go around trying to mate with trees, so why are they trying to have sex with our noses?"

-- Bobby G.

eventually, > dust will plug them and they will overheat. I just had a video board start to

fan > with compressed air, and all the problems went away.

You're lucky you caught it before it fried. A full "dust cap" is a fine heat retainer and could have easily cooked your VPU. Smart PC'ers use programs like Motherboard Monitor that will tell them when their fan speeds have dropped enough to indicate that they are getting clogged.

I do a lot of PC repair. I have a rough rule of thumb. In a normal environment, it's probably OK to let fans go unchecked for 24 months. Subtract 1 year if the equipment's on the floor. Subtract 2 months for each shorthair dog or car in the house, 4 months for every longhair. Subtract 1 month for fans under 80 centimeters and another month for those under 40.

One neighbor with 5 longhairs and a floor tower with a teeny video card fan needed monthly cleaning so we added some more fans and covered the front intake with air conditioner filter material held in place by a little magnetic frame. Now she just vacuums the front and the machine can go almost a year without a blow-out. (For anyone considering this, the clips on the cheap case face were so weak they broke during the procedure but we replaced them with some neo mags and hot melt glue so snapping the face off to vacuum the filter was even easier. Most case faces can't withstand frequent removal without those damn little tab clips breaking.)

I *would* post a picture of a super small video card sleeve bearing cooling fan and finned heat sink mount I removed from the 5 cat machine because I had never seen anything so completely caked in dust. The fan spun, but moved no air. I replaced it with a much larger ball bearing fan simply because it was less prone to clogging and the space permitted it. However, I see the picture police are on patrol, enforcing "laws" created when bits were moved around via acoustic modem. Like so many rules of that era it has been completely outmoded by technical advances. Anyone who says that posting a link is as easy as posting a picture with a message isn't being honest. Personally I'd rather see a relevant picture *with* the message rather than clicking on a link to who knows where.

One reason we got the central vac is that we like to air cool in the summer with a big attic fan and that brings in an awful lot of dust and pollen. Switching from A/C to "free air" cooling cured my wife's allergy. Turns out that being cloistered inside superclean, highly filtered office and A/C house hyper-sensitized her to pollen. She used to sneeze up to nine times when she left an A/C'ed building and stepped out into the late spring air, which *is* mostly pollen. Our standing joke is "we don't go around trying to mate with trees, so why are they trying to have sex with our noses?"

-- Bobby G.

Is that the output from the vacuum or the motor cooling?

With no air flow, the air in the blower will warm up as it sucks up the motors power, even without a motor being inside.

I would be sure there would be a really high current even without any current flowing.

Huh?

With no air flow, the air in the blower will warm up as it sucks up the motors power, even without a motor being inside.

Do you have Outlook express set to "group messages by conversation" under "view", "current view"?

IMHO most nntp servers deliver messages in random order. It's up to your browser to sort them in the order you wish to read them in. (see Bob F message)

Robert Green wrote:

Yes. This isn't about that.

Each message to usenet moves along a different path from the originator to the server that "feeds" me. Some messages take longer to arrive depending on where they originate. This has nothing to do with my browser settings and everything to do with the delays a post might encounter in finally getting forwarded to my NNTP server. News posts aren't instantaneous.

For example, it's entirely likely that a message posted from very far away will arrive well after a post from a nearby server, even though it has an earlier send date and did, indeed, start its journey earlier than the closer post did.

-- Bobby G.

Our points were: your browser sorts them out into any order you desire.

NNTP timing doesn't matter, within a few hours, of course.

Each message to usenet moves along a different path from the originator to the server that "feeds" me. Some messages take longer to arrive depending on where they originate. This has nothing to do with my browser settings and everything to do with the delays a post might encounter in finally getting forwarded to my NNTP server. News posts aren't instantaneous.

For example, it's entirely likely that a message posted from very far away will arrive well after a post from a nearby server, even though it has an earlier send date and did, indeed, start its journey earlier than the closer post did.

-- Bobby G.

Hmm. I use MSOE and that never happens to me. FWIW, I have FIOS (fiber to the house).

Same old moronic ideas.

Your news browser software doesn't make any difference to your NNTP presentation order. It gets what your NNTP server presents it, headers first and then as requested.

roblem is now that

If your sytem is blocked, the motor will in fact draw less current. The more outlets open/in use, the more current is drawn and the motor slows down. Being blocked is just the same as the outlet being closed/ not in use. Hence a blockage is not detectable except that there is no "suck".

Not in the slightest odd. It is a centrifugal pump, accelarating air from nil speed to several hundred miles an hour. If the air flow is cut off, there is no air getting in to accelarate. So it's not doing any work except friction losses. So the motor speeds up. Electric current reduces. Simple. This applies to all centrifugal pumps BTW. There is no way of determining the difference between motor running/no hoses connected and blocked. If the thing is cutting out, it's probably the thermal overload because of over heating due to the cabinet. Portable vacuum cleaners rely on the cleaning air sucked through the hose for cooling but central plant cannot as all the hoses may be shut off. Large central vacuum plants may have an induction motor (quiet running) but the same applies, except that the motor speed varies very little.