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To power up the board's 24v rail I shorted the NPN tranny and relay to ground. As per rating on the output diodes, FCH30B10, and the switching FET, 2SK3568, the 24 rail can output a wooping 30A continuously. Only question remain is the function of the opto next to the relay. The placement suggest it is sensing current on the primary side maybe?! Pin 7 on ...


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From the comment to @Mattman944's answer it appears that your question is based on a poor understanding of how voltage and current interact. Actually my main concern is whether the 2 fork connectors (as in pic above) would result in a short circuit scenario when they are in contact with each other. In effect you really want a short circuit. Both wires ...


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I have done that many times. However, I am not at all confident that it is a good practice. I would say that it would be bad to have more than two connectors on a terminal. When two terminals are connected, it would be better to use ring lugs than spade lugs. Of course that can only be done if the screws are not captive (or weakly captive). I would recommend ...


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I have seen this done many times, it is generally OK. What is important, is that the screw is fully engaged into the receiving threads. For many terminal blocks that I have used, the threads are mashed (if there is a technical term, I don't know it) on the other side to make the screw weakly captive. When you loosen the screw, you should never force it ...


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Small AC fans often fall into that category. It's cast as a bell shaped rotor, but you can see the skewed bars of the "cage", apparently formed by aluminium flowing into slits in the laminations during the casting process. These laminations contain the magnetic field quite well, but I can't put a figure on how close it is to the traditional internal rotor. ...


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Such motors typically don't have a squirrel cage but a massive bell-shaped rotor. Wiring is no different from an internal rotor induction motor. Starting torque is low, and the torque over speed curve has the typical huge hump because of the massive rotor. Really only suitable for fans and pumps. They come with a running cap usually. I have yet to find a ...


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LEDs are very tolerant of variation in current. I would choose a resistor value that will limit the LED current to 10 mA or less with a 14 Volt supply. The LED should still produce sufficient light when the voltage drops to 12 V. Many LEDs will produce reasonable light with only 1 - 2 mA. If you put an LED and resistor in parallel with a fuse or switch, ...


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If upstream of the wiring that leads to the AC power socket there is equipment that adds noise to that upstream feed line then, that noise (as a voltage fluctuation) will also be seen down stream at the unused AC power socket. That can capacitively couple to the CAT-5 cable (or any cable within reason) and it could cause cross-interference problems. Having ...


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You only have two wires coming in, so you don't have a ground connection. Most likely, the switch is a double pole, so that both sides are isolated when off. That way, if the appliance has a non-polarized plug, the element is isolated regardless of how it is plugged into a socket. If you have a double pole relay, you can wire one pole into each of the red ...


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You can send video frequencies through a slipring without trouble. Maybe more if you use LVDS and the arrangement is symmetrical enough. You can get commercial sliprings for a reasonable price, from China for example. However the operating lifetime might only be a few hundred hours for that sort of thing. I believe the heads in VCRs used a rotary ...


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I have spent 41 years working for local exchange carriers (ILECs). (The local phone company). I have also spent a good portion of my career designing SLIC circuits (subscriber line interface circuits). The older homes have quad "station wire" that is not twisted pair and is not impedance controlled nor balanced very well. DSL does work on quad. Seems ...


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I'm seeing a classic bimetallic thermostat with two control switches and one knob. I have deleted the outline and colourised it a little. Terminal 5 connects to the live 240V power Switch A connects this to terminal 1 when on Switch C is the bimetallic thermostat and connect terminal 1 to either the hot link or cold link and the anticipator resistor ...


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Your second diagram was a good find and is far superior. I think @Jasen is correct. The dashed line and the right-angled line between '5' and '2' are the controller board outline. This was neither clear nor consistent. This diagram also makes it clear that the 'RF' block is an 'Acc' or accelerator. I saw this trick used on the electrical carriage heating ...


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For industrial applications: PE for protective earth. Green / yellow for wiring. 0V for 24 V supply common is generally good because its meaning is clear. White with blue stripe is normal in Europe. +24V is usually split by fuses, circuit breakers or electronic fault protection units so additional wire numbering is required. +24-1, +24-2, etc., would make ...


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