Questions tagged [alternator]
Electrical generators that produce alternate current.
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Simple way to connect together two car alternators such that power flow can be bidirectional?
As I understand, it's not good to power a vehicle with two alternators, unless those alternators are protected in some way so that their voltage outputs don't go unstable (and die). I have an engine ...
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Why connect a 3-phase alternator's star-point to a rectifier bridge?
I noticed while troubleshooting a Denso alternator that the stator's star point was connected to the rectifier bridge. While probing with a multimeter, I think the schematic looks something like the ...
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Adding a charging lamp indicator to an alternator not having a connection for it
I have this car alternator wired as follows:
So it's connections are: B+ output for charging the battery, one brush to the regulator sense wire (exciter), and the other brush to ground. Is it ...
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Will two alternators in parallel share the load all the time or will switch the load from one alternator to the other?
If two identical voltage sources are connected in parallel and supplying a load the load current will be the same since the voltage is the same, but each source will supply half the current demanded ...
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Protection of my loads (batteries + equipment) from alternator
I have an aftermarket additional alternator (24v, 100A) installed in vehicle without external regulator (don't know about internal regulator). I have found this alternator locally probably used ...
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How to connect a digital meter between alternator and batteries?
We are using a 24 V, 100 A external alternator in our vehicle to charge leisure batteries. We need to monitor the alternator’s voltages and current on a digital meter but the alternator is grounded ...
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Crank an electric generator gasoline engine by using its alternator
Currently I have a gasoline generator (2 kW 230 Vac single phase), which has an electric starter. I'm searching for a potential replacement, but the brands I like doesn't have one around that power ...
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Does car alternator speed increase during load dump?
I am trying to understand the mechanism of voltage surges during load dump in automobiles.
As per this article -
The load-dump event has two components. First is the pulse amplitude (VP), which ...
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Voltage generated by individual coils goes down the larger the number of coils
I'm trying to make my own alternator & study the physics behind it.
So I have a circle of magnets rotating over 4 coils, forming a square (90 degrees each).
When I remove 3 coils from the square ...
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Does using a car’s electricity use up more fuel?
My understanding is that a car’s engine drives an alternator, which generates electricity to charge the car’s battery, and that all electrical power is then taken from the battery.
If so, does this ...
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Solution of a differential equation of a RC filter (alternating voltage) and graph
I'm trying to solve the differential equation of a circuit on the capacitor for the first half-period (the capacitor is initially discharged):
So far, I have this differential equation:
$$RC_{1}\frac{...
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I need to know what the resistance of the stator and rotor windings are
How do I calculate the resistance value of an alternator stator?
2.5 kW
50 Hz
220 V
8.3 A
12 V
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LTspice model single-phase motorcycle alternator
These days I'm dabbling in the design of a regulator for a 50cc motorbike, and I have a doubt how I can simulate the alternator on LTspice. Doing various tests on LTspice I arrived at a sinusoidal ...
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In AC circuits, angles and frequency are measured in radians rather than degrees. Why?
Why do we use radians instead of degrees when working with alternators and the like? The maximum induced EMF in an alternator will be a completely different value if one calculated ω in degrees per ...
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Permanent magnet vs wound alternator
I have a buggy/go kart project, and am currently trying to decide on a battery charging solution.
It is fully custom, so it is up to me to choose the device and build mounts, pulley ratio, etc. Many ...
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What are overhang conductors?
I am asking this in the context of synchronous generators.
From the textbook "The Performance and Design of Alternating Current Machines", page 421, under the heading "3.Synchronous ...
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Why is this ideal diode bridge rectifier simulation in LTSpice not working as expected?
I'm trying to simulate a full wave bridge rectifier circuit with the capacitor filter. The alternating voltage supply is 30 V at 50 Hz.
The peak value for the voltage across the load is 28.5 V. ...
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How do I safely power a triphase motor and an electric hoist with a triphase AC alternator?
The alternator has 12 kW, 21.7 amps and 400 V. For the motor we have 3/3.3 kW, 11.7/6.8 amps then 220/380 V and 250/440 V. The electric hoist we have 900 W and 220-240 V.
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On a 12 V car alternator with possible failure of the rectifier diode causing drainage, could an electronic component be added in-line near battery?
On a 12 V car alternator with possible failure of the rectifier diode/s causing drainage, could an electronic component be added in-line near the battery? Such as a voltage regulator or diodes in line ...
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Charging a LiFePO4 battery from an alternator
I have a power bank consisting of two LiFePO4 cells connected in parallel. They will used to power a range of 12 V electronics e.g. fans, fish finder, USB chargers, L.E.D lights and potentially a ...
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Voltage output of a engine alternator
If an alternator is rated at 100A/13.5V then that's 1350Watts.
Assuming an external regulator and a external rectifier what's to stop that same alternator outputting 28A/48V.
Everywhere I have read, ...
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Understanding alternator wiring
The alternator on a 2018 mitsubishi outlander along with many other vehicles has a 4 wire connector going to it. They are labelled as follows:
G-Ground
S-Sense
L-Lamp
FR-Field
Ground - is self ...
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what force is required to rotate a dynamo or alternator
I am working on an initiative for a new product. The product generates a rotational output force from:
Input force of 14.73 NM
Input speed 120 rpm
Gear ratios from 0.5 - 2
The out rotation is ...
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Reactive power fluctuation
We have 6 Caterpillar gas generators 3520c.
One of them when synches with the grid. Its kVAR fluctuates over wide range and the aux voltage too and the excitation volt and current. We checked AVR and ...
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What happens if you connect an AC generator to an AC motor? [closed]
An AC generator (or alternator) converts mechanical energy into electrical energy. An AC motor does the reverse.
What would happen if we connect the two in such a way that the output rotational ...
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Actual Line-to-Line voltage from per unit value
In this question, I am able to find the per unit phase voltages using the symmetrical components. Taking the base MVA and base voltage to be the same as that of the alternator,
\$ (I_a)_1 = \frac{E_a}{...
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Can an alternator recharge a battery in an EV
Can you recharge a EV's electric battery with an alternator hooked up to the axle of the EV?
This question came from a conversation with my Grandpa, and I was looking for an explanation for him of why ...
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Looking for solution to energize a relay ONLY when the alternator is running
I added a DC-DC converter in my truck so that I can charge the Lithium batteries in my RV. To turn on the converter, I am using a relay that ties to upfitter switches in my Ford F350 truck. This all ...
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24 V alternator to 24 V motor
I plan to run a 400 RPM, 400 W, 24 V AC alternator through a bridge rectifier, then through a 25 V smoothing capacitor, and then drive a 24 V, low-RPM DC motor.
I would like advice on specifics. ...
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What is the net current through this LR circuit
Here is the problem which I was asked to do.
I started by the method of phasors considering first the upper branch of the circuit Drawing phasors as follows :
Then for the lower circuit i drew the ...
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Does Alternator Self-Excitation Require Rectification?
I am learning about self-excitation in alternators.
My understanding is that there is residual magnetism in the rotor. As it spins, this generates a current in a stator which is then fed to the (...
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Alternator's saturation in load and no-load conditions
When a ferromagnetic material is exposed to a magnetic field in which it moves, some voltage is induced in the material. If you increase the magnetic field, the voltage is increased up to a point, and ...
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Alternator motor on 3 phase power
Hi was wondering would a alternator work as a motor if supplied dc power to the rotor and 3 phase ac to the stator. Have seen a lot of posts and videos turning it into a bldc motor but none on turning ...
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Design principles that prevent overcharging of batteries in older vehicles without undercharging
This question is regarding older (10 to 30 years old) cars which did not have a smart solid-state or electronic charger built in. Basically, lead-acid batteries in such cars were (and in cheaper cars, ...
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Using bridge rectifier on failing alternator output?
I have a bridge rectifier (because it was what was readily available as an integrated part) rated at 150A which I'm using to protect against intermittent reverse current (battery draining) in an ...
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Car battery > inverter > battery Maintainer > Same car battery = jumper cables in the trash?
I'm wondering if I have my car battery hooked up to a power inverter hooked up to a battery maintainer hooked up to the same car battery will it prevent me from needing to jumper cable my car?
I ...
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Designing an automotive alternator's voltage regulator - how to avoid magnetic saturation in the rotor?
NB: See final edit. The question is based on a false premise
Friends are making a test-bench for automotive ("Lundell") type alternators.
They were supplied with an example alternator plus a ...
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Three phase power supply for test purposes
I work in the electrical industry and deal with mainly three phase power.
I'm trying to broaden my knowledge of scopes and power quality and the only time I really have to do this is at work and that ...
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Can steel nails be substituted for the silicon steel laminate in a motor/generator/alternator?
This is as diagram of a generator/alternator in which steel nails are used in place of silicon steel laminates:
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Honda CBX 1979 Regulator/Rectifier - Lipo (lifepo4) battery
I exchanged the OEM battery (PB) of the CBX 1000 motorcycle with a Lifepo4 12V battery. It is smaller, lighter and has a much better CCA. However, the connector (wires at the bottom side of photo) ...
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Charging battery using a three phase alternator
I want to charge a 672 VDC (182 kWh) battery pack using a 25 kW three phase alternator (679.8 VDC at 4000 rpm, current = 38.5 A). Can anyone suggest how to design the system? The alternator is powered ...
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Why are all the phases connected together on this old alternator
I got my hand on an old car alternator. I can't figure out how it works. What bugs me is that it look like all the phases (and neutral) are connected together right at the output of the stator coils.
...
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Shape of magnets used in an AC generator and its relation with the obtained waveform
Suppose we are dealing with an elementary AC generator having a single coil armature located between the curved north and south poles of a magnet(like the ones found in toy DC motors-only two poles). ...
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48V Lithium Battery Cutoff Detection Circuit
I'm building a power system using four x 48 V 100 Ah lithium batteries in parallel (48 V 400 Ah nominal). The batteries are already purchased, there is no going back. The cells cannot be accessed, ...
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What is the intuition behind the formula P = 2n in computing alternator stator poles?
So from my reference for alternators and even in the Internet, it says that the number of poles P, produced in the rotating field is P = 2n where n is the number of stator slots/pole/phase. I've seen ...
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How long should one let the motor turn (witout driving) to re-charge the car battery, after having using it to charge a laptop's battery [closed]
I'm going to spend 1 week with no electricity. I won't need any for everyday life (I do this each year), except to charge my laptop's battery (10.8V, 5.2Ah, 57 Wh) three or four times.
I have a car ...
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How does a lead acid battery accept more current when it is discharged than when it is charged if the resistance is higher when it is discharged?
I'm just trying to get my head around the above question. It doesn't seem to follow Ohm's law. Could someone please explain what I am missing in this?
Below is a chart I found of the changing ...
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How can I test the rotor winding of a single phase brushless alternator on a generator?
Context Generator runs but no power output from the alternator.
The manual gives Ohm readings for the stator, excitation and rotor windings. The stator and excitation coil are to spec and have no ...
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Current limiting at 100 amps
What options exist for limiting current in this scenario?
I have been searching for an option and it looks like I need to reduce the field on the alternator but I don't understand enough to know if ...
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Selecting Capacitor to reduce AC ripple from Car Alternator - LED Indicators only work when Engine Off
My neighbour has recently installed some aftermarket LED indicators, when the engine is switched off the units work as expected, switching from white headlight mode, to blinking yellow mode.
When the ...
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