http://efly.co.il/forums/attachment....1&d=1278429836
To the moderators request i have translated this review to English
as well
I have recently received a the V-plus lipo pack in order to test the pack and it's performance on my trex 500ESP helicopter.
On this review i will examine the battery's performance, both on spread sheet and at the field
the V-Plus lipo was provided by the online store Century-RC
The platform on which all the tests were made is my Trex 500ESP helicopter
with the stock power setup, including the align 500L and stock 60A ESC.
here is a picture of what i will be reviewing:
http://efly.co.il/forums/attachment....1&d=1278429836
So first, some dry figures
Manufacturer:------------------V-PLUS----------------
Dimensions:--------------137mmx42mmx33mm--------
Weight:-------------------------420g-----------------
C rating (constant):--------------45C-----------------
C rating (burst):------------------85C-----------------
from the specs alone one can see that the V-PLUS pack is extreamly light
in relation to its spesefications
After adding some Velcro and a connector the V-Plus's pack weight was:
http://efly.co.il/forums/attachment....1&d=1278429400
The Test
after 5 break-in cycles, i made two flights with the pack
both flights were hard 3D and each flight lasted 5 minutes
with the second flight being a-bit harder the the second (can be seen in the graphs)
A logger was connected between the ESC and the battery pack during all three sessions
the logger recorded the voltage and current consumed from the pack in each separate flying session
the logger itself is the EAGLE TREE V3 LOGGER.
The In-flight DATA
in this segment each flight has it's own chart. In each chart there are two graphs:
The green graph represents the battery's voltage
The blue graph represents the Current consumed from the battery
both charts are calibrated so the X axis represent the time, and the left and right Y axises represent the Voltage and current.
this is the chart from the first flight session with the V-PLUS lipo
http://www.efly.co.il/forums/attachm...0&d=1278413073
In this flight 2092mAh were drained from the pack
this is the chart from the second flight session with the V-PLUS lipo
http://www.efly.co.il/forums/attachm...9&d=1279540135
In this flight 2197mAh were drained from the pack.
in order to get a better view of the batteries quality here is a closeup of the second chart:
http://www.efly.co.il/forums/attachm...0&d=1279540135
under load (high current consumption) the batteries voltage drops
the better the quality of the pack, the less it's voltage will drop under load,
and after the high current peak ends the pack will also return to it's original voltage quickly .
from the above graph one can see that after the high amp peak ends the packs
voltage returns to its former state almost immediately, and under load it the packs voltage
doesn't drop significantly.
this states the the V-PLUS pack is of very high quality.
the affect of these characteristics in flight us that the head speed of the heli won't drop significantly under load
and will climb up as soon as the load is finished.
My feeling, as the pilot, during the flight session
as stated before, each flight lasted 5 minutes
throughout the flight the power, as well as head-speed remained constant.
the first thing i noticed while flying was the added power i had in flight.
not necessarily added power for climbouts and such (even tough i did feel some power addition )
but sustained and constant power even under load.
while flying the helicopter and doing various maneuvers there was no significant loss of headspeed
and as soon as there was no load, the headspeed just shoots back up!
this resulted in giving me the ability to make my maneuvers more easly ans smoothly
with no power limitations during the maneuvers (unlike with other packs that i have flown).
another thing is that there was no power sag during the last minutes of each flight so i could continue flying as hard as i wanted throughout the flight.
To sum' it all up
I think that the V-PLUS pack is excellent for a number of reasons:
* It has a small physical size, making it easier fitting under the helicopter's canopy.
* Its high constant and burst C rate give amazingly constant power throughout power demanding maneuvers.
* It is very lightweight, which contributes to the feeling of added power
I really enjoyed making and writing this review, but i wouldn't be able to make it
without the help of some special freinds
special thanks goes to:...
Maayan and Itsik the the moderators, for providing the V-PLUS pack
Maayan Dreamer- who personally handed me the V-PLUS pack at the field
Eyal - (Maayan's freind) who provided the logger to perform all tests
Century RC- for the battery itself
until the next review...... :rolleyes:
Elad Dov
