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18

The manual states that the panel has "blown fuse indicators" - red LEDs that will light when the fuse is blown. The simplest way to do this is to connect an LED and current-limiting resistor in parallel with the fuse. With a blown fuse (or no fuse) this would allow a small current to flow in the circuit - probably enough to light your test light ...


18

No, you shouldn't do this. The problem is that the breakers won't share current equally because they're not totally identical and their contact resistance might vary[1]. This means that one of them will trip much faster than the others, causing their total current-carrying capability to be much lower than expected. Additionally, the four breakers won't open ...


16

Because motor coils are inductors, it takes a bit of time for the field to build up. Thus, for high-speed use in one direction, you can bias the position at which the commutation happens with respect to the magnetic field. If the commutation leads a bit, the motor will generate more torque for the motor current, and it'll go faster -- in that direction. ...


12

It has been known for over 100 years that the optimum brush angle for minimum sparking is not exactly 90 degrees. This sweet angle is somewhat load-dependent. Many large vintage DC machines had a manual brush angle adjuster to minimise sparking. When the expected load and direction are reasonably well known, like on a car starter motor, a fixed angle is ...


11

It will function, but using standard plugs and sockets for the wrong voltage is a spectacularly bad idea. This relies on you being in total control, remembering everything about your setup forever, and making no blunders... Every novice goes "oh, I can handle that"... but that is simply not realistic, and the standards bodies who set electrical ...


8

The motor has phase advance and is optimized for spinning in one direction over the other. It isn't symmetrical. Look at the backplate, it might have curved screw grooves to rotate the angle. This is the adjustment for phase advance.


7

Don't use cheapos or misapply equipment when the right stuff is readily available. Schneider's Square D "QO" load centers (service panels) and breakers are, frankly, the finest residential service panel offered in North America. They are specifically rated for 48 volts DC and Square D can supply breakers rated as high as 120 volts DC. As far as ...


3

Probably your circuit is oscillating. Since you don't have an oscilloscope, you can try measuring the op-amp output on the AC range of a multimeter. Also check the supply rail and verify that reads close to zero (most multimeters will read zero for a DC input on an AC range). If so, the solution is to decouple the heavy capacitive load of the MOSFET gate/1 ...


3

No, you can't use the module to charge batteries in a same pack simultaneously with the same power supply. That will short out the batteries via the modules together. The modules are meant to chage one cell only. Connecting them in parallel means shorting the battery cells as they are connected in series inside the pack but parallel at the poer supply side. ...


3

The "AC 250V 3A" rating is the maximum that the switch can handle. If you would use such a momentary button: and connect it to the PC's motherboard then the switch would need to handle about 5 V at a very small current. This is a lot less than 250 V and 3 A so the switch can handle this perfectly fine, nothing will blow up. I don't think you ...


2

You could build an inverter using a MOSFET that would look something like this. simulate this circuit – Schematic created using CircuitLab


2

Why there is not 8 turns on each side? Because 6 is all that is needed to switch the gate. It's not like a push-pull driver which would be symmetrical. So if I need 400V, there will be the same ratio? 5:3? Yes. If you want to change the output voltage then change the number of turns on the secondary. Reduce to 4/5 = 80% of the turns required for 500 V. I ...


2

So I should be looking for relays with a rated current of about 25A? You are currently running a 14A motor through 6A relays. They aren't going to last very long, especially since a motor is an inductive load. You need relays rated for at least 14A inductive load. In practice a motor can draw a much larger current when starting up, than when running. So ...


2

According to the Amazon page, the LEDs operate at 15mA, and their max current is 20mA. It is a bit confusing, but it looks like they drop 3V. Two of them would drop 6V. If you have a 9V battery, that is 3V that must be dropped across your resistor. (Of course the 9V battery will vary in voltage, but we will ignore that for now.) To find the resistor divide ...


2

If you are OK with using transformers, a simple audio transformer with a center tapped secondary will convert from unbalanced / single-ended input to 3-wire balanced output, and does not require a bipolar power supply. simulate this circuit – Schematic created using CircuitLab In this circuit, the transformer needs to be able to tolerate whatever DC ...


2

Wait, it's on the DC or AC panel? On the AC panel it would be normal to have a voltage (in a no-load condition) due to capacitive coupling, even if the breakers were open. You could measure that voltage with a multimeter and it would be usually a small fraction of the full voltage, but possibly approaching the full voltage depending on the situation. However,...


2

The difference between AC and DC switches is the contact rating inside. AC voltage basically goes up and down past zero, so if there are any electrical arcs they extinguish themselves when the voltage crosses zero. DC stays constant, so any electrical arcs will just keep going. You can use them interchangeably but DC switches will have better contacts. For ...


1

If the design doesn't support it, then don't run remote sense like this, in most DC DC converters it will cause instabilities in the feedback loop. I tried this years ago thinking I could cause the loop to neglect the wire resistance, what I got instead is a unstable feedback loop because of the added series inductance. The biggest problem is placing the ...


1

Now that you have clarified that you do not want to use transformers, here is a circuit that may possibly suit your needs. simulate this circuit – Schematic created using CircuitLab The op-amps can be single supply. They are biased to 1/2 of Vcc. This circuit will run in the CircuitLab simulator. Since you may be using 8 of these circuits per device, ...


1

I briefly read the specs on one of the Omnicharge devices. It tells me it will supply 100W of 120/240VAC. That translates to an input of around 30A @ 3.7V. That is not too unreasonable if they choose their mosfets carefully. If we were talking about 500W, then the losses would start to mount up and you'd generally want to go to a higher DC input voltage. ...


1

What you need is a "latch relay" (or "two-state relay"). I have used in the past the ones I attach (Omron G6J); then Fujitsu does very similar ones. This model carries up to 1 A, but you can parallel the two output contacts. Then, the maximum dc voltage is 110V, so at lower voltage you have some room for "a little bit of more current&...


1

Consider each white LED as a 3V Zener with a 15 mA nominal rating and 20mA max. Thus with 9V- (2x3V) = 3V. ... / 15mA = ? ohms


1

Anti-spark power supply connectors make the contact in 2 phases Phase 1: A series resistor allows possible capacitors to get charged less violently. This reduces inrush current peak and the spark when the contact is not established. Phase 2: The extra series resistor is bypassed to create the final low resistance contact If your lights have electronic ...


1

i belive that you are using something like this diagram in your wiring , since you`re using 2 channel relays ,you have 4 states for the relays, 1- ch1 on ch 2 on => this will connect both terminals of motor to the dc which will result in hard breaking, 2- ch1 on ch2 off => this will run the motor clockwise/clock side based on your connection 3- ch1 is ...


1

24VAC only has a peak voltage of 33.9V (24*1.414) So I the specified MOV looks reasonable. You get two diode drops with the bridge (-1.4) so 33.9 becomes 32.5Vdc. Instead of a zener here, I would pick a TVS diode (Transient Voltage Suppressor). They are fast and able to take large transients and have finer voltage resolution choices when compared to zener ...


1

You don't. You have a battery available to power your motor. You can use the same battery to power the relays and simply use the output from the receiver as a signal. Optocouplers would be ideal for this as the LED inside is polarity sensitive and thus will only work in one direction. You can then use the optocoupler output to switch the relays. Galvanic ...


1

It will only be +220V DC if the charger has its negative output connected to ground. There is no reason why this has to be so. Many DC power supplies are isolated, with no connection between the output terminals and any of the input power terminals.


1

A small electric outboard ,You may find one second hand ,they are 12 volt DC with built in controller ,don't rob for parts use the outboard, use your motors for shop tools


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