Some Power Supply Repair Jobs Only Make Things Worse

How bad is it when your repair business involves repairing repairs?

Pioneer Magnetics, a maker of high power AC to DC and DC to DC standard and custom switching power supplies, recently shipped its 700,000th power supply since it started counting in the 1980s. By COO and President Jerry Rosenstein’s estimates, approximately 10% of the number he figures are still in use-or 35,000 units–should be coming back for repair or refurbishment each year.

The actual number is more like 1,500.

It’s not likely that huge numbers of these power supplies are out there happily operating years past their expected lifeline. (Though the MTBF of power supplies has gone from 25K hours just a few decades ago to over 1M hours today.) The fact is that no matter how well made, power supplies-with hundreds of components and many moving parts including a fan-are the weak link of many systems. Many are noisy, hot, and simply live a hard life.

Some wind up in environments that they were not designed for, like the Pioneer power supply in a Quansat Hut in Hawaii with wind, rain, and salt water pouring in. Unbelievably it wasn’t the elements that did it in, says Rosenstein, though he says a little conformal coating would have helped immensely. “Actually a gecko got in, and ‘kaboom.’”

Ruling out extreme circumstances, Rosenstein says that a good power supply should last five to ten years before needing repair or refurbishment. He suspects that the many of the other 33,500 units he estimates are due for repair go not back to Pioneer, but to the dozens of third party power supply repair houses that have sprung up in recent years. Not that there’s anything intrinsically bad about third party repair, and, in fact, Pioneer Magnetics itself has some certified repair houses.

“I’m not saying they’re all bad by any stretch,” says Rosenstein. On a recent tour of a local repair house, however, he says that he noted boxes of capacitors from the 1980s and old fan motors on the shelves.

And lately he says he is seeing more units coming in exhibiting signs of a botched repair job. “They’re out of warranty, they’re all clunkers,” says Rosenstein. “I can’t tell you how many we’re getting back where it’s obvious that someone tried to do a repair and botched the job. We’ll get a bunch back with a common “bad repair” problem - the same broken wires, the same wrong components, you name it.”

Repairing a power supply isn’t quite as simple as swapping out a few components. As a case in point, Rosenstein says that Pioneer has developed a special technique to repair components that are mounted on a ceramic daughtercard. “There is a mix of through-hole and SMT components on the card, and we use special equipment to repair the faulty components without damaging the good ones,” he says. “But we’re seeing boards coming back to us for repair, where clearly someone tried to repair something but used the wrong soldering iron and then ruined pins on the good components and burned out circuit traces on the board.”

Here are two examples of botched repair jobs that came into Pioneer Magnetics for re-repair:

And a power supply that clearly a third party repair house did not know how to pack for shipping:

Why would anyone risk a bad repair on a product that retails for thousands of dollars? Two words: Cost savings. Rosenstein says that his company’s prices start at $400 for simple repairs and go up from there. Some third party repair houses charge as much as 50% less. “It’s amazing that people take the most expensive component in the design and start looking for a cheap deal when it comes to repairs,” he says.

Rosenstein believes it’s always better to have the power supply company do the repairs. But if a customer would like to work with a third party, Rosenstein says that at the very least they should conduct some due diligence before signing on the dotted line, especially if the repair prices seem almost too good to be true. A good place to start, he says, is by confirming they have the basics covered, like good ESD control and up-to-date inventory. Better yet, he advises partnering with a third party repair house that’s been certified by the OEM.

On its website, Pioneer Magnetics has posted images of some of the botched repairs done by third party repair houses.