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...
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...
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.
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...
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...
Hi all. I'm repairing an audio amp. The output devices are T03-can F15N and F15P. No other markings, date code or anything. I've searched the web with no useable results. I guess 3055's & compliments would probably do, but I'd like to do a proper job. Any takers?
Thanks, Steve.
Hello all. I've been offered a quantity of 63V 6800uf caps, but the're date stamped 1996. I vaguely remember being told that the electrolyte degrades, or that the working voltage decreases if they're not charged regularly. This was in 1976, so whilst the technology has, no doubt improved, is...
I'm currently specifying components for a machine which is to use a free-standing 11kW hydraulic power pack. I usually use Harting type connectors for valve control circuits; no problem there. However, is it acceptable to use the industrial standard red 3-pole+E circular IP44 connectors as...
I recently encountered a manufacture and test situation where a small pcb requires a 230VAC test prior to shipping.
The circuit uses a series 0.33uf cap as the dropper for a number of leds. No bleed resistor is present on the board, so a random level of charge remains when the power is removed...
