Announcement
Collapse
No announcement yet.
Heli Field Clinic at OHR
Collapse
X
-
I have a lengthy query though so please bear with me:
I have installed WR BECs for almost all my prized birds since 2005 without any issues. Every WR unit has been flawless.
Just last weekend, I acquired the KDS Agile 5.5 from a nice bro so I decided to use Hercules Super BEC WRL-HBECCS7 to power the electronics at 6v each. However, as I was changing the dip switches on the BEC, I noticed that the voltage reading would somehow behave erratically and jump from the preset of 7.4v to 5v. I tried different lipos ranging from 3s-6s lipo all with the same adverse voltage drop. In addition, whenever I touched the dip switches on the BEC with a pincher, the voltage reading would jump and there was some kind of glitching sound emitting from the unit as if a component/s had been soldered incorrectly.
Despite my suspicion that something is not right, I went ahead to use the WR BEC and 30s into the maiden flight of my new Agile 5.5, the 120a hv esc cut off prematurely which nearly resulted in a crash. It was NOT the money but effort (& deprivation of sleep) to see it all gone in an instance. And I also lost an expensive lipo in the process. I am NOT insinuating that WR BEC had caused the crash but is it possible that the esc cut-off was caused by the BEC glitch (if any)? Me and Bro Liang tried to BITCH-pump the servos after the incident but there were no brownout issues on the JR-921 rx. Nothing broken on the Agile but felt damn shitted and FARKED-UP cos i destroyed a brand new canopy from Liang...
On Monday, I wrote to WR with regards to this issue. Appended below is the reply from WR:
"Hi Henry,
Thank you for your inquiry regarding Western Robotics Hercules BEC.
With your feedback regarding the voltage jump from 7.4V to 5V sounds like the DIP switch must be worn down, that is why the 7.4V switch might not be contacting mechanically and therefore set it back to 5V as if the switch is not switched on. The switched needs to be replaced. If your BEC is purchased within 90 days with a proof of purchase we can replace it under warranty. However, if it is over the warranty period what we can provide you is a 40% discount on a new replacement unit of your choice and what we recommend would be our Hercules BEC Pro Mini as a replacement. http://www.western-robotics.com/WRL-HBECSPM
However, the ESC should not cut off due to a BEC glitch as it is independent of each other. Unless you have the ESC internal BEC powering with another BEC in parallel which is not recommended as this can cause failures with power conflicts."
In view of the above-mentioned, may I consult Doctor Lawrence on my next cause of action please? With particular reference to the line (bold & underlined), how true is that??Heli-ADDICTION:
Mikado Logos, RaptorG4s, X7F, 600ESP...
JUST one more Logo...for the month.
-
LOL, no reply from the Dr. I think he is not in SG.
Allow me to reply on Dr behalf. Hehe.
WR is right. The dip switch is giving you the problem.
You can get a dip switch from Sim Lim Tower and replace it.
Or just pull out the dip switch and solder wire to do the voltage selection
(so that you will never have dip switch problem again but you need to change
the wire each time you want to change the BEC voltage)
The ESC is controlled by the throttle signal. If you have a glitch on the BEC voltage, it will affect the
voltage supply to the Rx (or satellite) and FBL controller, this will in turn produce a throttle signal with glitch as well.
The glitch on the throttle signal will affect the behaviour of the ESC.
Just like any electronics devices, the supply voltage to it has to be stable. So when you have a glitch on
the supply voltage, it will produce unpredictable results on the output signals.
Comment
-
Thanks for the clarification! I decided to change the bec last night. Hopefully no more issues. I hv used HW esc in the past with great success so I would expect no less from tthe current one. Many thanks for advice rendered.Heli-ADDICTION:
Mikado Logos, RaptorG4s, X7F, 600ESP...
JUST one more Logo...for the month.
Comment
Comment