Need new converter: 14.4v or 14.8v?

Why oh why oh why do some of these fools INSIST on placing critical electrolytic capacitors next to vertically stacked ceramic resistors and large toroid inductors?

The fan in the power supply WFCO does almost nothing for a living, and reversing polarity on a Meanwell or Mega power supply muffin fan keeps the toroids, caps and transistors cooler. Are these designers on hookah power or what? I soused the Meanwell's, all of them bi-polar transistor heat sinks with Arctic Silver and then shot the discretes, heatsinks and case with an IR. Wow what a difference. Like 10-15 degrees DELTA T cooler, identical loading.

Industry has changed -strike that- "degraded" to a chew and spit philosophy.

I have sold maybe forty 120vac commercial ching-chong LED lamp fixtures and have built an equal number. Guess what the DIMMER commercial fixtures are failing the chips. My 30% brighter (driven at max ma) "same wattage" lamps have yet to fail a single one.

The real loser is the environment. Garbage that will never see proper recycling. Rare earth metals returned to the earth unrecoverable. Gold and Silver lost for no reason.

The world is now MEDIOCRE. PFFFTTTT!!!

Sounds as if we are making de-soldering / soldering a bit more complex than it really is. A requirement is a QUALITY temperature adjustable soldering iron / station, good ones are several hundred $$$$$. A vacuum sucker and solder wick work fine for standard 2 layer boards however it's a different story when you get 6 or 8 layer PCB's or as I have been dealing with a 26 layer circuit board with pressed in fitting.

Yes, Mex Panasonic Caps are IMHO the very best of the best. There are many different series Panasonic caps most if not all are very good.

From my experience most converters have simple to work with two layer PCB's (circuit traces on both sides with components only on one side) however many of the smaller sub-modules are 6 layers or more with SMD devices attached to both outsides which making getting components off them a real PIA.

Get a small ALUMINUM HEMOSTAT and use it whenever you can to protect diodes, caps and transistors.

NinerBikes wrote:
I, for one, would like to learn how to desolder and solder sensitive electronic components on a circuit board. Anyone willing to teach me?

I do remember having to heat sink a few components before soldering, clamping a big metal object to a leg to be soldered to take the heat away from the component, but that was back in electric shop in Jr high school, 7th grade, in 1971... I might be very rusty, components have changed some. We are not talking chips here, just capacitors, right?

Soldering tutorial

Desoldering is done with solder wick or using a desoldering tool. The solder is heated and then quickly withdrawn from the trace. These bulb desoldering irons work well. Solder wick is effective if only working on a few components.

This tutorial on electronics may prove valuable to you: NEETS, Naval electronics training

Heat and component damage are usually controlled by time, on and off the lead, and iron temp. I also use a clip that has a spiral copper wire that acts like a heatsink when soldering diodes or some other chips.

KJINTF,

I went with Panasonic brand. They have a 50,000 hr low ESR cap that I seem to like. You recommended Panasonic, I extrapolated it :D

Rude n Crude De-Soldering...

Spread thin coat of electrolytic grease over areas you don't want molten solder to stick to...

Using a can of pressurized computer "puff puff" cleaning air and a pair of goggles, heat the area to the point where solder liquefies then give it a blast of air through the straw.

Clean greased areas to be worked on with a Q-tip and auto gasoline dry (alcohol). Grease up the area you just worked on.

This is real "Bring Your Bowie Knife To A Steakhouse" technique, but it's a lot faster than solder wick braid plus the PC side of the board gets greased in the process...

I, for one, would like to learn how to desolder and solder sensitive electronic components on a circuit board. Anyone willing to teach me?

I do remember having to heat sink a few components before soldering, clamping a big metal object to a leg to be soldered to take the heat away from the component, but that was back in electric shop in Jr high school, 7th grade, in 1971... I might be very rusty, components have changed some. We are not talking chips here, just capacitors, right?

westend

"Gentleman" I don't get called that very often

Yes, if the converters (we are talking a Switch Mode Power Supply "SMPS" aka newer version converter) open circuit voltage is <13.2Vdc I would say a component has failed or is in the process of failure. Remember each make and model differs somewhat.

No need to replace all the caps. IMHO that would be a waste of time and money. Small caps in the feedback loop for the PWM control of the output voltage are a typical failure mode. They cause the lower output voltage issue. Increased ESR Equivalent Series Resistance not the actual capacitance value change causes the lower voltage.

If you do not have an ESR meter - then post up a make and model and I would be happy to supply a list of the common failure parts for that device. I keep records on all repairs, last count several hundred converters have come this way. Always looking for more keeps me entertained and out of the local watering hole.

KJINTF wrote:
Iota converters fail just as much as all the others
Last count I have 15 or 20 of them here for spare parts

Typical failure are the CAPs again just like all the other brands
A GOOD quality *ESR* (Not the standard capacitor tester) meter and 15 to 20 minutes plus <$5.00 in parts and you should be good to go again

The DLS Series has the dual Voltage jack which can be used to get the extra when needed voltage

Ken,
You were the gentleman I was referring to in a previous post on this thread. Excuse a bad memory.

Do you find the output of less than 12 V to be indicative of a bad component?

IME, since these converters have a small component count, if an amature wanted to have at it, replacing all the caps wouldn't be that difficult. FWIW, I have a Hakko desoldering tool that eliminates stress but wick would do the job for a small board as discussed here.

i've been using a PD 70 amp for 3 months
ever since i sent a powermax converter back to Florida for warranty service in March 2016
no word from them, no answer to email, no answer to phone msg

buy any thing BUT a powermax

IMO WFCO is better than powermax