Recent content by hit_it

Well, it's working great. Maplin gave me a diode - the bloke there actually knew what he was talking about which was good - diode now strapped across relay in reverse. I haven't fitted a resistor - PS is only 300W - and the relay has been left on for hours with no sign of anything other than...

To both of you - thankyou - just wish this place had been here 20+ yrs ago when I did my physics A level :) PS is pretty dead on 12V - I have a decent digital multimeter. Resistor - if I go to Maplin and ask for a 1.4Watt 100watt resistor suitable for 12VDC...

Hi, thanks for the replies, much appreciated. Q1 - DC resistance is 102 ohms. So power dissipated would be 12 x 12 / 102 = 144/102 = 1.4 Watts Coil is maybe only 0.5" x 0.5" x 0.5" in size. Therefore if I bung a 1.4W resistor in series with coil, I'm protecting the coil correctly, yes...

Hi, I have a central vacuum system that has blown it's circuit board up. Basically a hoover with a low voltage switching system to fire the motors up. Finding a new board will be difficult so I'm going to rebuild the control system. I can solder, can rewire a house, but the finer points of...