Doug Ingraham
Jun 01, 1996, 01:00 AM
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<title>Speed 400 Motor Analysis</title>
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<pre>I did an article about a year ago that looked at using Speed 400 motors
for LMR applications. I thought it was time to update this info since my
computer models are better now and I know a bit more about what is going on.
Since most of the contests focus on 7 cells I will do the same here. The 4.8
volt motor cannot be used on 7 cells direct drive with any of the props
programmed in my table so I am leaving it out of this section of the analysis.
These first charts focus on direct drive with the common motors and I used
the Sanyo N-500AR cell specifications but there is a cell that you can
get in the US that is very close to this in specifications. It is the
Sanyo N-500A cell. The data sheet shows only one difference between
these cells and that is that the N-500A cell weighs 3 grams more than the
N-500AR cell. So the numbers generated should be very close. Later I
will show the effect of different types of cells on select motor/prop combos.
Glossary:
BEST The operating point where the best efficiency would be realized.
Effic Efficiency (just the motor).
MAX The operating point where the maximum power would be extracted.
MTV Motor Terminal Voltage.
Win Watts into the motor.
Wo Watts out of the motor.
Wout Watts out of the motor.
Graupner Speed 400 7.2V on 7 Sanyo 500AR cells.
BEST 3.2 Amps 8.2 MTV 15774 RPM 18.3 Wo 71.1% 570 secs
MAX 9.0 Amps 7.7 MTV 9325 RPM 34.9 Wo 49.8% 199 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
MA 5.5x4.5 7.9 6.8 11730 54.1 32.6 60.2% 50 mph 262 sec
MA 6.0x3.0 7.9 6.7 11904 52.9 32.2 60.9% 34 mph 269 sec
MA 6.0x4.0 7.8 7.5 10986 59.1 33.8 57.2% 42 mph 239 sec
GR 4.7x4.7 8.0 5.0 13795 39.9 26.9 67.5% 61 mph 362 sec
GR 5.0x5.0 8.0 5.8 12877 46.3 29.9 64.6% 61 mph 310 sec
GR 5.5x5.5 7.9 7.2 11391 56.4 33.2 58.9% 59 mph 251 sec
GR 6.0x5.5 7.8 8.2 10276 63.8 34.5 54.1% 54 mph 220 sec
GR 6.0x3.0 7.9 6.6 12014 52.2 32.0 61.4% 34 mph 273 sec
GR 6.0x6.0 7.8 8.6 9806 66.8 34.8 52.0% 56 mph 209 sec
GR 7.0x3.0 7.8 8.4 10046 65.3 34.7 53.1% 28 mph 214 sec
RB 6.0x3.5 7.9 7.0 11522 55.5 33.0 59.4% 38 mph 255 sec
APC 5.7x3.0 8.0 5.8 12844 46.5 30.0 64.4% 36 mph 308 sec
APC 7.0x3.0 7.8 8.2 10243 64.0 34.5 54.0% 29 mph 219 sec
APC 7.0x4.0 7.7 9.0 9336 69.9 34.9 49.9% 35 mph 199 sec
Graupner Speed 400 6.0V on 7 Sanyo 500AR cells.
BEST 5.8 Amps 8.0 MTV 22259 RPM 34.3 Wo 73.6% 307 secs
MAX 16.4 Amps 7.2 MTV 13264 RPM 63.4 Wo 54.0% 110 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
MA 5.5x4.5 7.3 14.8 14594 108.0 62.8 58.1% 62 mph 121 sec
MA 6.0x3.0 7.3 14.5 14851 106.1 62.5 58.9% 42 mph 124 sec
MA 6.0x4.0 7.2 16.0 13559 115.3 63.4 54.9% 51 mph 112 sec
GR 4.7x4.7 7.6 11.2 17667 84.8 56.4 66.5% 79 mph 160 sec
GR 5.0x5.0 7.4 12.8 16272 95.6 60.2 62.9% 77 mph 140 sec
GR 5.5x5.5 7.2 15.4 14115 111.4 63.1 56.7% 74 mph 117 sec
GR 6.0x3.0 7.3 14.3 15005 105.0 62.3 59.3% 43 mph 126 sec
RB 6.0x3.5 7.3 15.2 14303 110.1 63.0 57.2% 47 mph 119 sec
APC 5.7x3.0 7.4 12.9 16212 96.0 60.3 62.8% 46 mph 139 sec
It is pretty clear that same prop with same batteries will net you LOTS
more power (almost twice as much) when switching from the 7.2V to the 6V
motor. For racing the ones to try are the Graupner Cam Speed 4.7x4.7
(when we can get them in the US) or the Graupner Cam Speed 5x5 (which is
available). For powering sailplanes the Graupner 6x3 folder or the Robbe
6x3.5 folder are the ones to try. I like the Graupner a little bit
better than the Robbe but there doesn't seem to be a lot of difference.
I always get slightly longer flights with the Graupner.
The 500 size cells are just about perfect if your event has a 2 minute
motor run which I believe is what the ES-400 models fly. Since you need
more duration for use with Pylon racing (4 minutes I believe) you need to
use larger batteries in order to get the 240 seconds. The following
charts will include the S-400 6V motors and just the Graupner 4.7x4.7
and 5.0x5.0 props but with different size cells.
Graupner Speed 400 6.0V on 7 Sanyo KR-600AE cells.
BEST 5.8 Amps 7.9 MTV 22144 RPM 34.0 Wo 73.6% 370 secs
MAX 16.0 Amps 7.1 MTV 13252 RPM 61.7 Wo 54.5% 135 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.5 11.1 17544 83.0 55.2 66.6% 78 mph 195 sec
GR 5.0x5.0 7.4 12.7 16147 93.2 58.8 63.0% 76 mph 170 sec
---
Graupner Speed 400 6.0V on 7 Sanyo N-650SC cells.
BEST 5.9 Amps 8.1 MTV 22596 RPM 35.4 Wo 73.8% 394 secs
MAX 17.7 Amps 7.4 MTV 13293 RPM 69.2 Wo 52.4% 132 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.8 11.7 18062 90.8 60.3 66.4% 80 mph 200 sec
GR 5.0x5.0 7.7 13.4 16676 103.2 64.7 62.7% 79 mph 174 sec
---
Graupner Speed 400 6.0V on 7 Sanyo N-800AR cells.
BEST 5.9 Amps 8.1 MTV 22596 RPM 35.4 Wo 73.8% 485 secs
MAX 17.7 Amps 7.4 MTV 13293 RPM 69.2 Wo 52.4% 162 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.8 11.7 18062 90.8 60.3 66.4% 80 mph 246 sec
GR 5.0x5.0 7.7 13.4 16676 103.2 64.7 62.7% 79 mph 214 sec
---
Graupner Speed 400 6.0V on 7 Sanyo KR-1000AE cells.
BEST 5.9 Amps 8.0 MTV 22367 RPM 34.7 Wo 73.7% 611 secs
MAX 16.8 Amps 7.2 MTV 13277 RPM 65.2 Wo 53.5% 214 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.6 11.4 17793 86.8 57.7 66.5% 79 mph 316 sec
GR 5.0x5.0 7.5 13.0 16410 98.0 61.6 62.9% 78 mph 276 sec
---
Graupner Speed 400 6.0V on 7 Sanyo KR-1200AE cells.
BEST 5.9 Amps 8.0 MTV 22413 RPM 34.8 Wo 73.7% 732 secs
MAX 17.0 Amps 7.3 MTV 13282 RPM 66.0 Wo 53.3% 254 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.6 11.4 17843 87.6 58.2 66.5% 79 mph 377 sec
GR 5.0x5.0 7.5 13.1 16459 99.0 62.2 62.8% 78 mph 329 sec
Since the program doesn't take into account unloading and some unloading
does take place the duration figures are probably a little low. But the
relationships between the different types of cells should remain fairly
constant. The 650SC and 800AR cells have the same internal resistance
which explains the identical figures except for duration. It looks like
you need 800AR cells in order to finish a 4 minute race but I have heard
that the people who have access to the N-700AR cells can finish a race
when they use those cells so some unloading must be taking place. In all
cases the differences in the cell types will affect the output volts by
only a couple of percent. I have flown my Mini-Viper on N-270AA cells
and it flew beautifully. I could tell that the power was down, but
nearly 2 ounces less weight is significant when the plane weighs 17
ounces and it had about the same vertical performance. The flight just
didn't last very long.
Note:
The currents for the MA props seem high to me. I guessed at the prop
constant and made it between the measured values for the large props and
that of an APC but it looks to be better than this. It is an area for
further study.
This completes part one of the article. In part 2 I will look at gearing
options.
</pre>
<pre>By Doug Ingraham of Lofty Pursuits
<a href="http://rcgroups.com/shared/nospam.php?u=dpi&d=rapidnet.com">dpi(at)rapidnet.com</a></pre>
</body>
</html>
<head>
<title>Speed 400 Motor Analysis</title>
</head>
<body bgcolor="#FFFFFF">
<pre>I did an article about a year ago that looked at using Speed 400 motors
for LMR applications. I thought it was time to update this info since my
computer models are better now and I know a bit more about what is going on.
Since most of the contests focus on 7 cells I will do the same here. The 4.8
volt motor cannot be used on 7 cells direct drive with any of the props
programmed in my table so I am leaving it out of this section of the analysis.
These first charts focus on direct drive with the common motors and I used
the Sanyo N-500AR cell specifications but there is a cell that you can
get in the US that is very close to this in specifications. It is the
Sanyo N-500A cell. The data sheet shows only one difference between
these cells and that is that the N-500A cell weighs 3 grams more than the
N-500AR cell. So the numbers generated should be very close. Later I
will show the effect of different types of cells on select motor/prop combos.
Glossary:
BEST The operating point where the best efficiency would be realized.
Effic Efficiency (just the motor).
MAX The operating point where the maximum power would be extracted.
MTV Motor Terminal Voltage.
Win Watts into the motor.
Wo Watts out of the motor.
Wout Watts out of the motor.
Graupner Speed 400 7.2V on 7 Sanyo 500AR cells.
BEST 3.2 Amps 8.2 MTV 15774 RPM 18.3 Wo 71.1% 570 secs
MAX 9.0 Amps 7.7 MTV 9325 RPM 34.9 Wo 49.8% 199 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
MA 5.5x4.5 7.9 6.8 11730 54.1 32.6 60.2% 50 mph 262 sec
MA 6.0x3.0 7.9 6.7 11904 52.9 32.2 60.9% 34 mph 269 sec
MA 6.0x4.0 7.8 7.5 10986 59.1 33.8 57.2% 42 mph 239 sec
GR 4.7x4.7 8.0 5.0 13795 39.9 26.9 67.5% 61 mph 362 sec
GR 5.0x5.0 8.0 5.8 12877 46.3 29.9 64.6% 61 mph 310 sec
GR 5.5x5.5 7.9 7.2 11391 56.4 33.2 58.9% 59 mph 251 sec
GR 6.0x5.5 7.8 8.2 10276 63.8 34.5 54.1% 54 mph 220 sec
GR 6.0x3.0 7.9 6.6 12014 52.2 32.0 61.4% 34 mph 273 sec
GR 6.0x6.0 7.8 8.6 9806 66.8 34.8 52.0% 56 mph 209 sec
GR 7.0x3.0 7.8 8.4 10046 65.3 34.7 53.1% 28 mph 214 sec
RB 6.0x3.5 7.9 7.0 11522 55.5 33.0 59.4% 38 mph 255 sec
APC 5.7x3.0 8.0 5.8 12844 46.5 30.0 64.4% 36 mph 308 sec
APC 7.0x3.0 7.8 8.2 10243 64.0 34.5 54.0% 29 mph 219 sec
APC 7.0x4.0 7.7 9.0 9336 69.9 34.9 49.9% 35 mph 199 sec
Graupner Speed 400 6.0V on 7 Sanyo 500AR cells.
BEST 5.8 Amps 8.0 MTV 22259 RPM 34.3 Wo 73.6% 307 secs
MAX 16.4 Amps 7.2 MTV 13264 RPM 63.4 Wo 54.0% 110 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
MA 5.5x4.5 7.3 14.8 14594 108.0 62.8 58.1% 62 mph 121 sec
MA 6.0x3.0 7.3 14.5 14851 106.1 62.5 58.9% 42 mph 124 sec
MA 6.0x4.0 7.2 16.0 13559 115.3 63.4 54.9% 51 mph 112 sec
GR 4.7x4.7 7.6 11.2 17667 84.8 56.4 66.5% 79 mph 160 sec
GR 5.0x5.0 7.4 12.8 16272 95.6 60.2 62.9% 77 mph 140 sec
GR 5.5x5.5 7.2 15.4 14115 111.4 63.1 56.7% 74 mph 117 sec
GR 6.0x3.0 7.3 14.3 15005 105.0 62.3 59.3% 43 mph 126 sec
RB 6.0x3.5 7.3 15.2 14303 110.1 63.0 57.2% 47 mph 119 sec
APC 5.7x3.0 7.4 12.9 16212 96.0 60.3 62.8% 46 mph 139 sec
It is pretty clear that same prop with same batteries will net you LOTS
more power (almost twice as much) when switching from the 7.2V to the 6V
motor. For racing the ones to try are the Graupner Cam Speed 4.7x4.7
(when we can get them in the US) or the Graupner Cam Speed 5x5 (which is
available). For powering sailplanes the Graupner 6x3 folder or the Robbe
6x3.5 folder are the ones to try. I like the Graupner a little bit
better than the Robbe but there doesn't seem to be a lot of difference.
I always get slightly longer flights with the Graupner.
The 500 size cells are just about perfect if your event has a 2 minute
motor run which I believe is what the ES-400 models fly. Since you need
more duration for use with Pylon racing (4 minutes I believe) you need to
use larger batteries in order to get the 240 seconds. The following
charts will include the S-400 6V motors and just the Graupner 4.7x4.7
and 5.0x5.0 props but with different size cells.
Graupner Speed 400 6.0V on 7 Sanyo KR-600AE cells.
BEST 5.8 Amps 7.9 MTV 22144 RPM 34.0 Wo 73.6% 370 secs
MAX 16.0 Amps 7.1 MTV 13252 RPM 61.7 Wo 54.5% 135 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.5 11.1 17544 83.0 55.2 66.6% 78 mph 195 sec
GR 5.0x5.0 7.4 12.7 16147 93.2 58.8 63.0% 76 mph 170 sec
---
Graupner Speed 400 6.0V on 7 Sanyo N-650SC cells.
BEST 5.9 Amps 8.1 MTV 22596 RPM 35.4 Wo 73.8% 394 secs
MAX 17.7 Amps 7.4 MTV 13293 RPM 69.2 Wo 52.4% 132 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.8 11.7 18062 90.8 60.3 66.4% 80 mph 200 sec
GR 5.0x5.0 7.7 13.4 16676 103.2 64.7 62.7% 79 mph 174 sec
---
Graupner Speed 400 6.0V on 7 Sanyo N-800AR cells.
BEST 5.9 Amps 8.1 MTV 22596 RPM 35.4 Wo 73.8% 485 secs
MAX 17.7 Amps 7.4 MTV 13293 RPM 69.2 Wo 52.4% 162 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.8 11.7 18062 90.8 60.3 66.4% 80 mph 246 sec
GR 5.0x5.0 7.7 13.4 16676 103.2 64.7 62.7% 79 mph 214 sec
---
Graupner Speed 400 6.0V on 7 Sanyo KR-1000AE cells.
BEST 5.9 Amps 8.0 MTV 22367 RPM 34.7 Wo 73.7% 611 secs
MAX 16.8 Amps 7.2 MTV 13277 RPM 65.2 Wo 53.5% 214 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.6 11.4 17793 86.8 57.7 66.5% 79 mph 316 sec
GR 5.0x5.0 7.5 13.0 16410 98.0 61.6 62.9% 78 mph 276 sec
---
Graupner Speed 400 6.0V on 7 Sanyo KR-1200AE cells.
BEST 5.9 Amps 8.0 MTV 22413 RPM 34.8 Wo 73.7% 732 secs
MAX 17.0 Amps 7.3 MTV 13282 RPM 66.0 Wo 53.3% 254 secs
PROP Mtv Amps RPM Win Wout Effic Speed Duration
GR 4.7x4.7 7.6 11.4 17843 87.6 58.2 66.5% 79 mph 377 sec
GR 5.0x5.0 7.5 13.1 16459 99.0 62.2 62.8% 78 mph 329 sec
Since the program doesn't take into account unloading and some unloading
does take place the duration figures are probably a little low. But the
relationships between the different types of cells should remain fairly
constant. The 650SC and 800AR cells have the same internal resistance
which explains the identical figures except for duration. It looks like
you need 800AR cells in order to finish a 4 minute race but I have heard
that the people who have access to the N-700AR cells can finish a race
when they use those cells so some unloading must be taking place. In all
cases the differences in the cell types will affect the output volts by
only a couple of percent. I have flown my Mini-Viper on N-270AA cells
and it flew beautifully. I could tell that the power was down, but
nearly 2 ounces less weight is significant when the plane weighs 17
ounces and it had about the same vertical performance. The flight just
didn't last very long.
Note:
The currents for the MA props seem high to me. I guessed at the prop
constant and made it between the measured values for the large props and
that of an APC but it looks to be better than this. It is an area for
further study.
This completes part one of the article. In part 2 I will look at gearing
options.
</pre>
<pre>By Doug Ingraham of Lofty Pursuits
<a href="http://rcgroups.com/shared/nospam.php?u=dpi&d=rapidnet.com">dpi(at)rapidnet.com</a></pre>
</body>
</html>