Help : motor /esc problem

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timberman
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Help : motor /esc problem

Unread post by timberman » Sun Dec 09, 2012 7:11 pm

I have a Hyperion HZ 5035-20 170kv and a pheniox 85hv with castle link, additional bec , using 2- 5s 4000 mah 15c lipos in series for 10cell , the motor specs online says1600-2000 watts but when on watt meter with18X10 prop only get 550watts and 18 amps. It seems like it is going to have a lot of power until around half throttle then it just seems the same power. What could I be doing wrong?
It's going in a 1/7 scale Top Flite Sea Fury weight 12.5lbs.(batt. inc)

http://www.b-p-p.com/product.php?pro...&cat=30&page=4

http://www.castlecreations.com/produ...hv_series.html
thanks
Dennis
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astroflyer
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Re: Help : motor /esc problem

Unread post by astroflyer » Sun Dec 09, 2012 9:48 pm

I checked the hyperion charts for that motor and see you are using the right prop and cell count. your batteries at only 15c are suspect however.

The fact that you see no power increase above half throttle says a lot. you need to put a watt meter on your system and check the voltage while running things up.

Do you have any way to check individual cell voltage ? might be a bad cell or two among those two packs, or the packs are old and lazy.

At any rate, 15c packs for that motor and plane are not a good idea.

Might be a slight possibility your ESC is not going to 100 percent throttle, but I would put my money on poor batteries.

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bdg
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Re: Help : motor /esc problem

Unread post by bdg » Sun Dec 09, 2012 10:00 pm

Dennis,

Take this with a real grain of salt as there are certainly members with MUCH more experience than me out there..... It sounds like your prop is too small for the load. I've pulled-up a prop calculator - which I have never used - and I think that I have entered info properly but the adage is accurate (garbage in = garbage out). The URL is http://www.ecalc.ch/motorcalc_e.htm.

The Hyperion motor Z5035/20 (170kV) with a 18x10x2 prop seems to be a theoretical power between 1100W and 1200W (taking into account normal motor losses):
Capture1.JPG
Change to a 20x10x2 and your power increases to between 1500W and 1700W. This seems to make sense but again the exact figures from the website calculations are unsubstantiated / not verified. Note that this prop seems to be the preferred for your motor (http://www.b-p-p.com/product.php?produc ... =30&page=4) but the 20x10 suggested prop size is actually cited for a 12S battery and not for a 10S. To me, you will require either a larger or greater pitch prop with the 10S OR possibly a move to the 12S.

I am not sure why you would only be reading 18-19A at 37V or so (10S). I assume that the prop rpms are continuing to climb as throttle is increased?

Just my initial thoughts.

Brian

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bdg
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Re: Help : motor /esc problem

Unread post by bdg » Sun Dec 09, 2012 10:13 pm

astroflyer.... good points for consideration. The 15C with a 4000mAhr 10S battery should be able to withstand 60A continuously (more than 2000W with a fresh battery). I've reworked the calculator (typo with the battery type - I had chosen 5000mAhr and not the 4000mAhr). The calculator suggests an 8C loading. The idea of a problem cell (as you've suggested) or even ESC might also be in the cards.

Reworked calculations:
Capture2.JPG

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timberman
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Re: Help : motor /esc problem

Unread post by timberman » Sun Dec 09, 2012 10:36 pm

All cells are and fully charged .
tomorrow going to do another run up, I actually have 20x10 going see if any diff.
do I need to make any changes within programming my esc (castle link ) or keep all factory settings, like timing, pwm switching rate etc

this is a setting of esc for programing ,which one is my motor?

Setting 8: PWM Switching Rate
Note: The following settings apply only to the Phoenix-35
and above.
Option Recommended Use
1 12 kHz Recommended for most brushless motors.
2 16 kHz Recommended for low inductance motors. RARE.
Suggested for Kontronik Tango motors.
3 24 kHz Recommended for very low inductance motors.
4 Outrunner
Mode
Recommended for all outrunner motors.


thanks
Dennis

astroflyer
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Re: Help : motor /esc problem

Unread post by astroflyer » Sun Dec 09, 2012 11:15 pm

I would recommend outrunner mode.

You old are your batteries btw?

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retiredVTT
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Re: Help : motor /esc problem

Unread post by retiredVTT » Mon Dec 10, 2012 1:27 am

Your Wattmeter is showing 550 Watts with an 18 amp draw....so your voltage is in the 30 volt range.

Definitely the 2 5S packs are sagging from their near 40 volt start.

You probably need two strong 6S packs which would give you around 46 volts start up, and if they can maintain a 45 amp draw you will have slightly over 2000 watts at take off.

Two 5S packs in series producing 38 volts with a draw of 52 amps would also give you 2000 watts at takeoff.

The problem is "internal resistance" within the packs. Right now it would appear that close to one half of your pack voltage is being used up (in the form of heat) just pushing them electrons out of the pack and through the motor circuit. Fresh packs have low internal resistance and therefore deliver more electron flow to the motor. It's sort of like trying to water the lawn with a 1/2" hose as compared to using a larger diameter hose. Hey..that brings up another element....your wiring should be at least in the 12 gauge area to allow them electrons to pass....'cause they get nasty when they're all bumping into each other....just means more heat...and heat is wasted energy..!


Bill
Bill
HEFA #5
MAAC #13708

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timberman
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Location: West Chezzetcook

Re: Help : motor /esc problem

Unread post by timberman » Mon Dec 10, 2012 6:56 am

Power%20System.jpg
Purchased from hefa member Bertrum
Motor:
Hyperion Z5035-20 170Kv
Max Efficient Current - 39~54A
Max Peak 20 sec - 75A
Power Range - 1600W~2000W
Input Voltage - 10S~12S
Io (@8.4V):(A) - 1.7A
KV: (rpm/V) - 170
Ri: (ohm) - 0.032ohms
Max Prop - 20x10E @12S
Weight - 24.51oz 695g
Diameter - 59mm
Length - 71mm
Shaft Diameter - 8mm

ESC:
Phoenix HV-85
Max Voltage - 50V
Max Current - 85A
Ri: (ohm) - 0.0015ohms
Weight - 4.2oz 119g

Power System.jpg

astroflyer
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Re: Help : motor /esc problem

Unread post by astroflyer » Mon Dec 10, 2012 10:27 am

I'm with bill and I feel it's the batteries.

Lipos age even if not being used and those have to be several years old as you never see 15c even mentioned anymore.

If you could bring the system out my way sometimes I could hook it up to some known five cells and check things out. we would have to change connectors through.

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timberman
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Re: Help : motor /esc problem

Unread post by timberman » Mon Dec 10, 2012 10:55 am

Done a test with watt meter , now I really confused:
all factory settings on esc
18X10 prop - 340watt 10A 32v
20X10 prop - 400 watt 13 A 32v

the first test the other day I think I changed the timing in the esc to get 550watts

I guess I'll have to start shopping around for new 5 or 6 cells
thanks to all for the help
Dennis

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