I was happy to see what the postman delivered to me today; a brand new Western Robotics "Hercules" high-voltage UBEC (HBEC-HV). Rated for up to 60v and 3.5A, this thing sounds very nice.
The website boasts high-efficiency and glitch-free operation, but we'll see about that!
First impressions: This thing is big and heavy! About the same size as a KoolFlight UBEC but weighs in at 33 grams. Most of that weight comes from the VERY large toroidal inductor. Everything on this looks quite beefy. The switching IC at the heart of the circuit had the part number scuffed off, so I don't know exactly which IC it uses, and I wasn't about to go online and hunt down what it
could be. It does have the same size and shape as the IC used in the KF UBEC, but that one is only rated to 40v.
Ok, some pics, with a couple showing the relative size next to a KoolFlight UBEC for reference:
On to the testing...
Since I don't have a DC power supply rated for anywhere near 60v, I took two of my 14 cell NiMH packs and put them in series. To keep the voltage fairly constant throughout the test, I charged them at the same time at ~1A. As a result, the voltage was steady at around 40v. Not quite 60v, but enough to test for typical setups. Here's a screenshot of the results:
The results are quite nice to say the least! Even pushing it beyond its 3.5A rating still maintained an acceptable voltage.
Temps were right about what I expected, and the website does say it will get toasty at high loads and to ensure adequate cooling. So, no surprises there.
Voltage output was right on the button at 6v unloaded. As the load increased, the voltage fell to only 5.8v. VERY nice!
Efficiency was at a respectable 86% @ 2.34A. Even when forced to produce 4.83A (38% beyond its rating), efficiency was still high at 84%.
I could not get any kind of AC voltage or frequency ripple (noise) reading at any load, so that says a lot for the glitch-free operation.
Drop-out voltage was quite decent considering the very large operating voltage range. Western Robotics advertises this UBEC for 9v-60v range, but I was happy with the output even at 8v.
Upon hookup, there is a decent initial spark to charge the input capacitor. But since most people will be using this along with a HV ESC, they'll probably be using a no-spark charging resistor for the ESC capacitors anyway, so that's not an issue.
All in all, this is a VERY nice UBEC. High current, high voltage, high efficiency, and VERY low noise. The only downside is the price at ~$55, but will work in any setup from 3s to 14s lipo. No false advertising here; this BEC lived up to the rated specs and then some!