T&L Publications

I've seen much more complicated circuits that isolate the cells of the battery and charge them in turn. I don't think something like that makes sense for this application Those systems are used when you want to get a charge into the battery ASAP - some charges seem to promise to get a full charge i...

Dimmers, especially older ones were notoriuos for failing after an incandescant light bulb blows . I forget the exact mechanism but it causes a voltage spike that blows the SCR. Not sure if newer models are also susceptable but if you buy a heavy duty one with a high current rating, it is less like...

It will be a 3 phase motor and I will update my schematic to show that. There are two ways to wire it up thou... STAR or DELTA.. I believe you find more Star configurations for Windmill applications.. so I will try that first. Alternators are (almost) allways wired in a STAR configuration. There is...

The hot bulb will receive about 90 percent of the power and the cold bulb about 10 percent. This might be a stable condition, but I don't know how to analyze it. The cold bulb, receiving some power will probably heat up slowly . As its filament't temperature raises so does its resistance and the po...

It's US 240 if you know what I mean. It's coming off of a stepdown transformer with a center tap and so from the two lines two the center tap (ground) is 120VAC. So I don't know how I should measure th voltage with the method I just described. Just use a small transformer with a 220 (or 240) V prim...

:shock: :shock: SAFETY WARNING :shock: :shock: If your ADC has its reference voltage (aka ground) tied to one side of the 220 V supply, you can use a voltage divider as was sugested. In that case, your entire circuit should be enclosed so it is not accesible to anyone. You shoult treat it as a hot c...

i have tried something like this before. especially with chriastmas lights..lol results weren't good .. the lower wattage lamp lights up way faster , and after a few times of doing this, the lower wattage lamp failed .. it lit up super bright. and then the higher wattage lamp glowed a bit..but they...

haklesup said: Batteries don't last as long as air tanks. Weigh a lot more too. I'm sure he was referring to the lifetime of the storage tanks vs the replacement rate of depleated batteries. ------------ Barring a puncture , the tank should last the life of the vehicle . In Argentina we have lots of...

I see this as similar to a flywheel. A way to temporarily store mechanical energy without the losses associated with conversion to and from electric. I think it is more like a very BIG spring than a flywheel. It just stores mechanical work (force x distance = pressure x volume) In ideal (=isothermi...

Dale: 30 mA the IC alone. Not bad, but still a waste 98% of the time when running on batteries: http://www.datasheetcatalog.com/datasheets_pdf/U/C/N/5/UCN5804.shtml The datasheet says Supply current Idd ( 2 outputs ON ) typ 20 mA max 30 mA A good part of that current should go to the output transis...

you should invest in a "Kill-A Watt" meter ($24 ebay w/ free ship, multiple vendors). ..........especially if those warts feel warm at any time loaded or not. A very "quick and dirty" way to find if it is drawing much power is to feel (or meassure) the wall wart's temperature af...

A synchronous motor might well draw mmore current at a lower voltage in order to maintain the load at synchronous speed A motor with tachometer feedback would probably draw more current with decreasing input voltage in order to maintain the output power of the motor constant. As I posted yesterday,...

An ac motor has a running amperage of 10 amps and the measured voltage is 120volts ac. If the voltage drops to 110volts An AC (induction) motor's current depends on the speed it is rotating. When the input voltage is decreased, il lowers its speed (** only slightly **) and increases its current (an...

to find if the TO-92 device is a UJT, JFET, mosfet, bipolar transistor, or what I would say that it's only a "garden variety" NPN bipolar transistor (ie BC548 or PN2222 or whatever you vave at hand) Colector to +V (bottom), emiter to the transformer's "primary" (top), base to th...

It occured to me that startup and possibly braking of the blade would demand the largest current but only for a short period of time. I think you'll find that motor braking is provided by short-circuiting the motor rather than using the power supply in some incredible way. A shorted PM motor that's...