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Let's Take a Trip Inside Budget Power Bars, Part Three

Round Three: The Usual Suspects

Our laundry list for today features the following:

  • TrippLite's TL604, $11
  • CyberPower's CSB404, $10
  • APC's P74-CN, $12

Those prices were valid when I started putting this article together. All three models have gone up by a few dollars, likely to pad margins on Thanksgiving and Boxing Day discounts.

Overall expectations are much higher in this third round. Let's get to it, shall we?

Our Seventh Contestant: CyberPower's CSB404

The smallest unit, sporting only four outlets, CyberPower's is also the only one with a rubbery cap on its power plug. Aside from the UL sticker, writing on the back contains the usual dry-location and no daisy-chaining warnings, along with the 500V surge suppression rating across any two conductors.

I would have preferred to get the CSB604, which was only $1 more, for this tear-down. But it would not ship from the same NewEgg warehouse as the other four, so I picked the CSB404 as a stand-in.

CyberPower's Packaging

CyberPower's front packaging is easily the most barren of the three bars, with little more than than the brand, product name, image and basic features. The unit promises a $25,000 protection warranty with 450J worth of surge suppression. Its side panel adds that the suppression can handle surges up to 7500A and mentions some degree of noise reduction from 150kHz through 100MHz.

Inside The CyberPower

Once again, we are greeted with the familiar outlet and metal strip arrangement. Here, though, we find a PCB soldered top-down on the breaker switch, which has only two terminals. It lacks the neutral connection an illuminated switch would require for power.

CyberPower's PCB

The soldering looks about as good as it is going to get. Getting a nice solder joint on thick metal tabs can be difficult, and part of the reason why they look crooked is because the breaker's tabs have been bent slightly to prevent it from popping off the PCB during soldering. The live and neutral switch islands come awfully close to each other without isolation slots, though that shouldn't be an issue until after the live-neutral MOV fails.

With the breaker being a panel-mount snap-in, getting the PCB out of there is going to require some extra work...

Some Desoldering Required

This is one of those occasions where I wish I had an SMD rework heat-gun: warm up both tabs and pull the PCB off. But I don't, so solder wick it is.

Managing to wick out enough solder from the cut-outs took much longer than expected due to the tabs holding solder in their wiring eyelets. The bent tabs did not help make extraction any easier, either.

CyberPower's Components

Once the PCB pops off the breaker, we get to see a fairly simple component arrangement with the three expected GNR 14D201K MOVs, a WTC thermal shut-off for live-ground and neutral-ground, the live-neutral MOV's thermal shut-off and a 22nF X-cap providing basic noise filtering. It's not exactly the most impressive EMI filter, but still better than nothing.

CyberPower's Switch

Here is CyberPower's breaker switch. You can see how one of the tabs is somewhat bent. It's not much, but still notable enough to make extraction tricky, as if those tabs' solder-thieving holes were not enough. This breaker switch simply gets snap-fitted to the bar's housing like almost all of the other bars so far.

CyberPower's Strip Connections

As far as soldered or welded strip connections go, it does not get much cleaner than this. The way strands are tightly packed together with intact plating says this was a spot-welded with just the right amount of power. There are no loose or broken strands either.

As you can see, CyberPower used winged-type contacts. If you are curious about strip dimensions, the power and neutral strips are 5.5mm wide by 0.5mm thick, while the ground strip is 4.5mm wide by 0.4mm thick after subtracting holes. This is roughly on par for power and slightly chunkier than average for ground.

Our Eighth Contestant: Tripp-Lite's TL604P

Instead of reiterating everything that's practically the same as the other bars so far, let's focus on what is different about this one. There's a little extra shoulder area to better accommodate an adapter brick and a protection status LED. This is the first bar with such an indicator. Also, molding on the back mentions a full set of line-to-line surge protections rated somewhat on the high side at 500V, so we can expect at least three MOVs.

Tripp-Lite's Packaging

Another fairly modest front side. There's not much to say when most of the product is fully exposed anyway. The back more verbosely reiterates the 790 joules surge protection, $20,000 equipment protection and lifetime warranty. Time to take a look at what this translates to inside.