Someone dropped a box there. I made a sharp swing to the right to avoid it, and broke my front end. Might have been better to just hit...

Someone dropped a box there. I made a sharp swing to the right to avoid it, and broke my front end. Might have been better to just hit it. The front wheel is shaking with squiring noise. Barely made it to the charger. Waiting for AAA.

I want to try this emergency battery charger: https://www.ebay.com/itm/185836877680 150W output? Or do they mean 150W LED bulb? Perhaps...

I want to try this emergency battery charger: https://www.ebay.com/itm/185836877680 150W output? Or do they mean 150W LED bulb? Perhaps 10W real output? What's the benefit of twin cylinders vs. the single cylinder version?

The "charge" functions are pretty easily understood. But, is the "engine start" function just a whopping big transformer-rectifier-filter...

The "charge" functions are pretty easily understood. But, is the "engine start" function just a whopping big transformer-rectifier-filter sitting behind the clamps? I'm speaking of the ~200A load current devices, not the smaller 50A; something along the lines of:

Cart with 2x 12v 33Ah progolf AGM lead acids. 1.5 years after fitting new batteries the available range is down to below 10%. I'm not clear what's...

Cart with 2x 12v 33Ah progolf AGM lead acids. 1.5 years after fitting new batteries the available range is down to below 10%. I'm not clear what's gone wrong. The charger in use has been a cheap chinese one with 2x13.7v=27.4v output. Single stage charging only. It has always been promptly charged after use, and never run below 50% charge. I checked the battery voltages after charge, they wer...

I'm setting up a UPS for my computer/comms equipment using an inverter/charger and battery from Amazon. The equipment draw is only about 40...

I'm setting up a UPS for my computer/comms equipment using an inverter/charger and battery from Amazon. The equipment draw is only about 40 watts measured with a Kill-A-Watt, but all the associated wallwarts use capacitive-input switching power supplies. That means they only draw current at line peaks. My seat-of-the-pants guess is that the duty cycle is around 10%, meaning that the aver...

Attention, this is one of those rare electronics-related questions :-) Will be rigging up a small power-failure backup system. Essentially a...

Attention, this is one of those rare electronics-related questions :-) Will be rigging up a small power-failure backup system. Essentially a 12V LiFePO4 battery (with BMS in there), inverter, solar panels, MPPT charger. When reading up on stuff and talking to people I found something very disconcerting. It seems that MPPT charge controllers can and often do commit suicide when operat...

After using a pair of inverter/charger circuits as UPS units for some months I've become curious as to how the trigger decides when to switch...

After using a pair of inverter/charger circuits as UPS units for some months I've become curious as to how the trigger decides when to switch from line power to the battery and inverter. Supposedly they trigger on wrong voltage or frequency, but they do it in less than a half-cycle, so it seems to be more than a simple relay. A cursory web search found nothing but I don't know the proper...

I am working on a simple USB charging circuit. Normally, the 3.6V NiMH bat= tery is connected to the device via the NC contacts of a relay. ...

I am working on a simple USB charging circuit. Normally, the 3.6V NiMH bat= tery is connected to the device via the NC contacts of a relay. When conne= cted, a 5V relay switch the battery to charge via a diode. So, a fully char= ged battery is around 4.2V. As someone suggested, i will put a parallel R = & C to reduce the hold current of the relay.=20 Questions: 1. What is the minimum ...

I'm working on a TP4056-based 1S LIPO solar charger which includes a load sharing (aka power path) function. But I don't have a panel to test...

I'm working on a TP4056-based 1S LIPO solar charger which includes a load sharing (aka power path) function. But I don't have a panel to test with. So I'd like to simulate the circuit in LT-Spice. But I've never used spice, LT or otherwise, so I was hoping to find an example of a solar panel equivalent circuit that I could import, then add the rest of the circuit, which is pretty simpl...

Hi, Here's a new SMPS switcher apparently coming out next year for...

Hi, Here's a new SMPS switcher apparently coming out next year for laptops: http://phys.org/news/2013-12-circuit-laptop-charger-brick.html It apparently has a "power reclaiming scheme" for higher efficiency, would this be conventional sync rectification or some other thing? It looks like power electronics is in for a big (r)evolution once the 300MHz+ designs start to spread! cheer...

Hi, I have constructed a DC-DC step-down converter using the MC34063. The circuit I use is very similar to the one shown...

Hi, I have constructed a DC-DC step-down converter using the MC34063. The circuit I use is very similar to the one shown here: http://www.eleccircuit.com/wp-content/uploads/2008/01/ipod-mp3-player-charger-by-mc34063.jpg My circuit does not have the Zener, output side LED and input side protection diodes (TVS1 and D2 in the circuit). The rest of the circuit is quite similar. The...

Again: "Cost - $700 million in costs could slow EV charger deployment across California. By CARB’s own calculation, an EMV chip reader...

Again: "Cost - $700 million in costs could slow EV charger deployment across California. By CARB’s own calculation, an EMV chip reader mandate will add approximately $3,000 to the cost of a charging station over its lifetime - $371 for the hardware and $270/year in operations and maintenance (O&M) costs" http://www.evassociation.org/carb.html For: 1. Allow simple an