Best Rated threads in ⏚ Electrical Engineeringshow all threads

Subject Author Posted Replies
 
How do I clean catalyst on gas soldering iron?
Can you help. I am new to this stuff. The catalyst on my gas soldering iron doesn't glow as red as it used to. Maybe some bits of material I used to file the iron's tip got into the catalyst. How can...
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Motor bogging down
The application of the motor is on a hydraulic lift. Originally the unit had a 15hp motor. Line voltage is 485v 3 phase. Someone at our company, decided to order a new pump unit, and ordered a unit...
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How to amplify alarm clock buzzer?
This cannot be difficult. But I cannot anything with a Google search. Is it possible to design an amplifier for the alarm buzzer? Since the alarm clock is probably an all-in-one chip design, I presume...
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How to disable charger circuit on APC UPS
Hello, I have this question posted in another group as well but I figured I'd give you folks a shot at it. I have two APC rackmount ups units. One is a 2200XL model which has a larger internal charger...
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415v Supply to Domestic Homes in the UK
Hi I have a normal domestic supply to a house in the UK. I have seen a printing press that needs 415v. I assume my house is fed with 240v, and not transformed within the house down from something...
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GFCI Repeated clicking noise...
I have a GFCI in my kitchen that seems to keep making a clicking noise. The GFCI is connected to one other outlet along the countertop. The funny thing is that it keeps doing this every 15 minutes or...
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3-pole breaker vs. 4-pole for a 3-phase wye
Consider the following: A 3-phase wye source is used to power several single phase loads in the same cabinet. Each load would be wired phase-to-neutral. It is desired to install a single circuit...
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rewinding motors (2023 Update)
I want to attempt to re-wind the feild windings in a 2000w angle grinder, i have removed and counted the old windings, though it got messy ,and i am only accurate to within + - 5, will this matter ?...
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208 vs 230?
I almost always work with pure 115V AC equipment, but now with the new Cisco 6500 equipment I am getting, I am little confused about something. In a house, you have two 115V supply lines of the same...
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Catastrophic failure SF6 Circuit Breaker
We have had a catastrophic failure of an SF6 circuit breaker. This breaker was used as a synchronising breaker for a CHP on our 11kV system. Does anyone have or can point me to articles on failures...
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Question on wiring a 240v Sauna heater?
O.K. Heres my problem. Previously, I had a 240 volt hot tub with a 50 amp Double pole GFCI. Recently replaced hottub with a 240v sauna. Now, according to the wiring schematic. I need one 240v line...
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Are damper motors required to have a disconnect?
The new Washington State rule says no. So where in the NEC does it say no? Here is the Washington explanation: "Do HVAC Damper Actuators Need Motor Disconnecting Means Per NEC Article 430? No, an...
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doerr vacuum pump
i hope somebody can help me. i bought a doerr pump at a garage sale the other day. they guy told me it had never been used but tis a little old. it has a strange plug almost looks like a 240 volt. but...
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Portable Generator Stator
Greetings All: I have been in the industrial electrical business for a long time. I am very familiar with motors being rewound and machined. I have been in business for myself now for about 8 months....
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Three Phase/Single Phase Voltage Fluctuations
Hi everyone. I hope this is the right group for this post of mine - hoping someone will have some insight to this one. Our house power supply is three phase (i.e. 230v/400v). Since I live in the...
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Dropper in 110v dc system battery charger
i have a single line (one line) diagram. you can see in : dropper that connected to control card? whats usage of a dropper in the circuit of 110vdc? have you a refrence for droppers and types? thnks.
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Two dimmers in series?
I am in the UK (230V) and have a 100W standing lamp with a dimmer wired in line with it's mains lead. I have recently got a remote controlled dimmer which plugs into the wall mains socket and then I...
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sg3525 ic advice for inverter
Hi All, I'm trying to use a sg3525 ic in a Sinewave PWM. I've looked everywhere and can't find a straight answer, so I hope that someone here with experience can assist. Question 1: How can I...
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Grounded neutral in an old sub-panel
The existing (old) sub-panel is fed by 2 phases and an uninsulated neutral conductor. There is no ground bus, return conductor to the service entrance, nor connection to a ground rod. The conductors...
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68
 
uneven brushwear in permanent magnet dc motors
Hello all... I race 1/24 scale cars that use high performance permanent magnet DC motors. Very common is an uneven wear characteristic where the brush in the hood connected to the negative or return...
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