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That's nothing

Where I work (warning ugly website ahead) one of our top salesmen was out on a startup on a 4160VAC starter. The customer asked him how wide the stacks were, so he took out his metal measuring tape and measured across the phases.

He was ok, by sheer luck, but the measuring tape has two very decent burn marks at each end where the voltage jumped out and grabbed it. He was thrown back quite a ways and didn't want to move for about twenty minutes, but he lived.

We develop sales automation tools for handheld pcs. we couldn't do that on a PDA. there is no keyboard. how can a sales person lookup a customer / part, or enter an invoice / order with a stylus touch pad. answer, you can't you need a keyboard.

I disagree. Sales should have next to zero use for a keyboard. Product lines, customers, price lists... should all be selectable WITHOUT a keyboard. We're designing internal applications for our sales force using Palm PDAs. The sales force will have a PDA and a portable DVD player.

Product demo videos will be on the DVD players and they can give out CDs with documentation and other goodies. The Palm handlelds will have a few apps for quoting and the standard email, time tracking, contact management and datebook applications available.

We used to give them laptops which had to be upgraded every year or so, were prime targets for theft, crashed and were generally used to play games instead of sell. Now we're replacing them for less money, less space and 10x the effectiveness. Throw in a folding keyboard for writing[1] faxes/emails and a modem and they have everything they need.

[1] - yes, the odd time a keyboard is needed but it's very infrequent.

A 130 volt MOV connected to a 120 VAC (RMS) outlet is going to blow within a few tenths of a second.

Actually it won't blow that fast. I'm hunting around for a power supply I can rip apart so I can cross the part to show you that I'm right but at this time I can't. Maybe later tonight I'll get back to you; depends on what the kids get into. :-)

Sorry, wrong. An induction motor will only generate power if it is turning faster than synchronous speed.

Hmmm, I guess that's why we have the current go through the roof when you're driving a pump and go to reduce phase angle, right? (I suppose you could say that when you reduce the phase angle you're changing the synchronous speed...) In the case of driving a motor with the UPS you can cause the bus to rise if you're in a high inertia situation. (pushing a heavy piston up and then gravity assists it in falling, this will push you past your synchronous speed as well.)

I can't speak for the designers of all UPS's, but any unit with either a pi-network or L-network (inductor input) output filter is going to soak up those spikes before they leave the box.

Perhaps it's because I'm in large industrial controls but would a 700W filter not be rather large and bulky?

*Unless it is a single-phase motor and you get it up to the speed where the start winding disconnects. If that happens, a single-phase induction motor will happily run backwards.

We (Benshaw) can get a three phase motor to rotate backwards with a six-SCR starter through a cycloconvertor type of firing algorithm. (actually the standard set of software will do 7 and 14% of full speed forward and 20% reverse.) We sell this feature quite a bit for bucket inspections and positioning as the client usually doesn't have need for a full-blown drive and doesn't want to pay 2.5x the price for one.

Sewing machines are just the start. Soon we'll see Game Boy interfaces to sheet metal cutters, lathes, drop forges and welding robots.

About 3 years ago, I designed a Gameboy cartridge which interfaced with the Benshaw RSD series of soft starters (I'm the lead designer) and worked with the unit to provide preventative maintenance and other goodies. The director of engineering said it was a toy and nobody'd use it.

Now I'm working on the Palm version and people have been demanding it for the last eight months. I'm going to email the link to this guy and see what he says now. :-)

I don't know where you're getting your data.

Palm V: Cute leather cover that turns the unit on when in your pocked due to bad design!

Get PalmV ButtonGuard v2. It turns off the button interrupts so even if you press it for a week the Palm won't drain the battery any harder. Much better improvement over the AlwaysOff hack.

Also about that leather case: I've had no trouble with it. It seems to displace the force against the screen very well. You could always get a PalmV RhinoSkin. I had one for my Palm Professional. Love it. Want one for the V.

Palm III: Flash upgradable
Palm V: Nope
Winner: Palm III

My PalmV seems to be flash upgradeable. Went from 3.0 to 3.3 (I think those were the version #s), and I have about 800K of apps in flash.

Palm V: Digs into the edge of my hand and has a habit of sliding out of my hand and plummeting to the floor.

You must have a very strange way of holding it, or you hold it too tight and have sweaty palms. I've never dropped my V because of the form factor. My Palm Pro, OTOH...

Palm V: Hot Sync contacts not compatible (won't even sync on an old Palm/Palm III cradle!!!!!)

Do you want backwards compatibility with everything? You can get a small device that connects your V serial port to any III-style accessory. Can't remember the name offhand but I believe someone has already replied with the link

For me, the V won. I needed something that was sturdy ((thin) aluminum beats plastic IMO), thin (the III is a pig) and wouldn't keep eating batteries. I get about 3 weeks out of my PalmV. I use it for appointments, phone #s, a programmable calculator (sorry can't find the link, it's by Gary Desrosiers), notes (and also BrainForest), DopeWars, diagnostic platform for the equipment I design, password storage, billing... It's a well used device.

BTW: All the apps mentioned which are replacements for standard PalmOS apps use the standard databases so I don't lose compatibility. Kudos to Iambic and Standalone Software for that feature, it was a big deciding factor when I chose their products.

Infogenius blows goats. Try it for a couple weeks and see. It's the same problem as the GB emulator for Palm. Just isn't meant to do it.

Faceball 2000 isn't exactly what I meant by raycasted 3D graphics. I was meaning more along the lines of Doom/Quake. Wolfenstein graphics are pretty "blocky", as are Faceball's.

developing for a handheld that's still being commercially developed for sounds really cool

It is. :-) I developped a little hardware dongle and software that talked to a reduced voltage soft starter (see here) via I2C. They called it too much of a toy so I now do it on a Palmpilot for 5x the price. :-)

'sides.. The GB is a $70 child's toy, which means that our techs can't break 'em. Plus, they can play Tetris on the flight home. :-)

I do it all the time.

this unit runs at 10Mhz and does it. I know; I designed it.

I however did not design the web page. Flames go to /dev/null. :-)

It's quite easy to do 115200 on an 8 bit processor using an RC oscillator. Stable? not if the temperature changes. 115200@4MHz? not unless that is pretty much ALL it's doing. as stated earlier, that leave about 6.8 instructions per bit. Not a lot if you're gonna be doing anything else besides sending and receiving data.