Search results for query: *

Yes, I agree; don't know why I came up with that figure! (probably the same reason I can't build an integrator).

On second thoughts, that's way ott. A 100R pot is only going to dissipate 1/8 watt, and that's not allowing for the v drop in the opto. Maybe up the +5V reg to 1A version to be sure.

Thanks very much, Dean. So it's really that simple, eh? To keep the pot current low, I guess I could just put a buffer after it and the unmarked R & C, which are there for the option of pwm pulses from a pc to control the setpoint.

I've designed a psu for hot-wire cutting. Whilst it works very nearly as I wanted, I've never had much success with the integrator stage of feedback loops and this one was no exception. Quick description: The hot wire load is fed with phase-angle controlled ac from a transformer. The trigger for...

Thanks again Scotty, for an interesting peek into the murky world of electro-semantics. I seem to recall your answering one of mine a couple of years ago with an equally enlightening slant.

Hmm, thanks, Scotty. I've searched for the replacement and found an interesting comparison document. Seems like time to fork out on a standard!

Oops! Yes, just got home (had to walk the last bit due to ice & snow). I'm in the UK. MCC = Motor control centre. Form 4 type 2 (and other variations) refers to barriers and segregation within the box. So it'll be european standards. Thanks for taking the time to look.

Good day all. I've just had my first form4/type2 mcc signed off. Being the first venture away from wardrobe type enclosures, I followed the advise of an enclosure manufacturer and had the enclosure equipped with busbars by a company who told me that they are accredited to undertake such work...

Thanks for the replies. Dinjin, I'm aware that unexploded blocks won't stretch; it's just that when included in a stretch-invoked window, they will change appearance to denote that they have been covered, but remain in the same position on the drawing when the stretch operation is made. IFRs...

Just changed to acad2009. The stretch function is not picking up blocks. Everything else within the right-to-left sweep is stretched, but blocks get left behind. Is this just a tick box somewhere? Any help much appreciated.

Thanks for that, Scotty. It's a resistive (heater) load, so it should look reasonably clean. &BTW, I've got a box of assorted high voltage thin film R's that I use for things like this. I've never burned-out any gear, but have had a few carbon deposits on my fingers... I think my "block" in...

Thanks, Scotty. I was going to 'scope two phases in differential mode, but I thought in advance that if I saw a sinusoid, I'd just put it down as an artifact and not the real thing(!) So, if the voltage across any two phases is a sinusoid, is it the case that all I need to do to...

Hi All. I'm familiar with and have built plenty of single phase ramp & comparator type leading-edge phase angle controllers, but currently have an application that requires the voltage to be derived from two of the three phases (UK supply). My maths is not up to creating an excel graph to...

Yes, I intend to emulate the internal H-bridge structure of the ic. At the end of the day, my comparator was merely a diy schmitt circuit, anyway. So a buffer would be neater, but I wasn't sure if I might have to adjust the switching (threshold) level due to unanticipated output voltage...

Thanks. I'll give it a go.

Watch out if you intend including an RCCD. There is a class (B-type) -not to be confused with B-type MCBs- that have a low pass filter in the earth line to eliminate nuisance tripping from switching spikes.

Hi all. I'm looking to increase the output capacity (current) of a stepper motor driver ic. Above about 4A, the only commercial units are complete "systems" on a board. So, in principle, how's this: Connect the existing outputs from the ic to a pair of comparators (with pull up/down) to clean...

...Or EasyPC by Number One Systems. I still use their DOS-based package (£94 in 1990), but they have "everything" now, including simulation and schematic capture.

Hmmm.... I won't say who, but he's a world-famous opera singer(!!) But for all that, not above asking, "Hey Steve, can you have a look at my amp? I was playing some rock & roll very loud through big speakers and it just stopped working." LOL.

Scotty: No secret, just been out for a few days! It's a Musical Fidelity, "Elektra E100". VE1BLL: I'm with you on the la-la land thingy. In the meantime... I've found out that they are just good ole' bipolars. I've ordered some MJ15024's & 5's. I'll check them on the 'scope. If they look...