Re: Relay controlled PSU thermistor
Simpler than this would probably be to use a single PIC microcontroller, a decoupling cap, a 5v relay, an npn/darlington and a diode. This way everything can run on the 5v standby rail... the relay shouldn't use more than 50-100mA.
The pic would have internal oscillator, brown out reset, watchdog timer etc, resets automatically when power is lost, and gives you the ability to set a proper timer until you trigger the relay.
http://www.digikey.com/product-detai...%2FP-ND/665881
For 0.58$ it's a nobrainer.
With the above circuit, I'd be concerned if there's a half a second or so power loss, the system may reset suddenly and your circuit still overrides the thermistor and the capacitors pull more amps than the fuse.
But in real life, the capacitors probably won't discharge that fast.
In regular power supply, it's not the transformer that pulls current, it's the large capacitors. In linear power supply it's the transformer, especially if it's a toroidal one.
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Machine: Autoclave.
Brand/Model: SANYO MLS-3780
Manual: (Sorry search option not working on this PDF)
Hello guys, this autoclave running with 2 thermistors already connected TH1 and TH3(on CN1,CN2 sockets). One for the water temperture and second one for chamber temperature. But there is another emtpy socket for optional third thermistor CN2 wich is for TH2 for object temperature. I wanna add the third thermistor TH2 to CN2 socket. But i can't figure what model/brand/value i need to use. In manual document, there is no info about TH1 and TH3 model number... -
Burco BCPLSAFWM5L 5 Litre Wall Mounted Automatic Water Boiler With Filtration UK 240v
Does anybody have any experience with these Burco units at all there is no record of them on the forum lol and a proper service manual would be nice. I invite you all to pesuade me not to botch repair it with a 5v relay, read on.
This unit was rescued from a skip 3 years ago, the only fault it had then was no backight display (plus it wanted a new probe set and top seal) but the screen was never an issue you can still see the screen as is and I just use it to get 5 Litres of very hot... -
Yesterday I successfully repaired a Middle Atlantic UPS2200R-IP that had inadvertently been used as a surge suppressor at our transmitter site. It has already been replaced with an updated one but it's coming home with me now instead of being e-cycled. To be specific, this is the MA model that has the blue backlit display and has been discontinued, although this design may have been used in many UPS units including the smaller Middle Atlantic ones in this series.
Here's what happened: We experienced a brownout/surge at the site, which damaged the UPS and took our broadcasting... -
Hello!
I'm looking at an original Xbox PSU: Foxlink ftps-0002 rev. B. The 12 V output is too low, and the 5 V output is too (?) high. Unfortunately I don't have an oscilloscope but only a DMM for diagnosis.
Measured voltages with no load:
After rectifier diodes
12V: 6.17 V
5V: 5.67 V
Secondary transformer pins AC measurement (really don't know if this says anything)
12V: 2-2.5 V
5V: 1.04 V
I also have another (working) Xbox psu from Delta. The same measures there, in order, being: 10.79,... -
Hi all,
Got this local made DC power supply (12/14V) given free as the transformer has melted. There is no marking or indication to identify what type or rating of transformer used.
Fyi,. I had a busted autogate mainboard with transformer with marking 13-0-13 . Is this the 13v dc type transformer?
My questions are
1. How do i test to see if the transformer is in good working condition?
2. Can this transformer (marking 13-0-13) be used to replace the melted transformer on the DC power supply?
Hope you guys understand what i was asking. My intention is...
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