a123 batteries or???.......
01-21-2008, 11:12 AM
#26
RE: a123 batteries or???.......
Hi Bob,
I have run my MKII with a 2-cell 2200mah LiPo. I had that in my F-16 until it went splat. Now the Lipo doesn't work so well[
]. Maybe its is a case where the 6 volt solenoids are OK at 8.4 volts but they get a little irritable at 9.9 volts. I wonder if a 2-cell A123 has enough juice to spin the 44 fast enough for the start. On the '54, the starter peaks at 30K. What's the number on the '44?.
You should box up that F-100, ship it and head out here for the Desert Jet Storm...............The weather has been so-so lately...I have actually had to wear LONG PANTS to the field....ugh!
John
I have run my MKII with a 2-cell 2200mah LiPo. I had that in my F-16 until it went splat. Now the Lipo doesn't work so well[
]. Maybe its is a case where the 6 volt solenoids are OK at 8.4 volts but they get a little irritable at 9.9 volts. I wonder if a 2-cell A123 has enough juice to spin the 44 fast enough for the start. On the '54, the starter peaks at 30K. What's the number on the '44?. You should box up that F-100, ship it and head out here for the Desert Jet Storm...............The weather has been so-so lately...I have actually had to wear LONG PANTS to the field....ugh!
John
01-21-2008, 11:25 AM
#28
RE: a123 batteries or???.......
oops, I was still asleep when I replied. A 3 cell A123 may be a problem.
No go on the Hun. I have it torn apart doing paint work.
The Spark is ready just need a test flight which means some warm weather.
I could just come and enjoy the weekend!
No go on the Hun. I have it torn apart doing paint work.
The Spark is ready just need a test flight which means some warm weather.
I could just come and enjoy the weekend!
01-21-2008, 11:44 AM
#29
RE: a123 batteries or???.......
Bob,
Bring it on with that Spark! I'm off work from the 5th to the 15th. Dave is coming out on the 6th. We've got chargers, balancers,generators, etc available. We can test at the SVF filed which is closer to my house. Breakout the AMEX card and drive across the river to CVG.......I'll pick you up at PHX. Dave has dibs on the guest room....Unless you want to double-up................Otherwise, we have plenty of room at the casa.
Vin,
You're an animal. I mean it was like 55° or something out there when I got to the field!
John
Bring it on with that Spark! I'm off work from the 5th to the 15th. Dave is coming out on the 6th. We've got chargers, balancers,generators, etc available. We can test at the SVF filed which is closer to my house. Breakout the AMEX card and drive across the river to CVG.......I'll pick you up at PHX. Dave has dibs on the guest room....Unless you want to double-up
................Otherwise, we have plenty of room at the casa.Vin,
You're an animal. I mean it was like 55° or something out there when I got to the field!
John
01-21-2008, 01:22 PM
#30
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RE: a123 batteries or???.......
ORIGINAL: cactusflyer
Chad,
I had a conversation with Gaspar about the A123s as well. It seems that know one knows, that is to say, for sure if they will work with the Wrens. I don't use a solenoid valve on the Kero but I checked and determined that the gas valve is rated at 6 volts. In order to learn something, I hooked up a 2-cell a123 pack to my old MKII MW-54 at the field today. The Wren is in in a Boomerang Intro and I have been using a 4600 mah Ni-MH pack for the FADEC. I flew once with the 4600 pack and then I plugged in the A123s. The start went well. It did seem to take a bit longer but the EGT temps were nominal. It was about 62° at the field. I'm curious to see how it would work with warmer ambient temps. I had to fly with the Ni-MH pack though due to CG considerations .......................Bottom line: My Wren will start and run fine with the 6.6 volt A123 pack. I plan on downloading the data from the FADEC to take a look at it.
Tailwinds,
John
ORIGINAL: SinCityJets
Gaspar emailed me regarding the Wren ECU. He stated he felt that the Wren starter motor would not work on 2 cells. His fear with 3 cells was that the kero solenoid might not hold up. He stated the solenoids came in a 6v and 12v flavor, so I am assuming they come stock with a 6v solenoid.
So far we know that Jet Central will work with a 2 cell A123 with no (known) problems, and Jet Cat's will work with a 3-cell A123 if the GSU is set to 8 cell nicad.
I put up an A123 info page for those that may have questions about A123's.
www.sincityjets.com/batteries/a123info.html
I will keep you posted as I learn more.
Gaspar emailed me regarding the Wren ECU. He stated he felt that the Wren starter motor would not work on 2 cells. His fear with 3 cells was that the kero solenoid might not hold up. He stated the solenoids came in a 6v and 12v flavor, so I am assuming they come stock with a 6v solenoid.
So far we know that Jet Central will work with a 2 cell A123 with no (known) problems, and Jet Cat's will work with a 3-cell A123 if the GSU is set to 8 cell nicad.
I put up an A123 info page for those that may have questions about A123's.
www.sincityjets.com/batteries/a123info.html
I will keep you posted as I learn more.
I had a conversation with Gaspar about the A123s as well. It seems that know one knows, that is to say, for sure if they will work with the Wrens. I don't use a solenoid valve on the Kero but I checked and determined that the gas valve is rated at 6 volts. In order to learn something, I hooked up a 2-cell a123 pack to my old MKII MW-54 at the field today. The Wren is in in a Boomerang Intro and I have been using a 4600 mah Ni-MH pack for the FADEC. I flew once with the 4600 pack and then I plugged in the A123s. The start went well. It did seem to take a bit longer but the EGT temps were nominal. It was about 62° at the field. I'm curious to see how it would work with warmer ambient temps. I had to fly with the Ni-MH pack though due to CG considerations .......................Bottom line: My Wren will start and run fine with the 6.6 volt A123 pack. I plan on downloading the data from the FADEC to take a look at it.
Tailwinds,
John
John,
The gas valve was the least thing Gaspar was worried about since it only runs at start-up. He was more concerned with the fuel solenoid since it would normally be running the entire time.
Let us know how it works out.
Chad
02-26-2008, 06:45 AM
#31
My Feedback: (2)
RE: a123 batteries or???.......
Hi.
I just want to let you all know that after considerable testing and data examination which took me almost two weeks
i now run my Boomerang intro with a Trefz tt66 (kj66, p80 variant) 21 lbs of thrust,
Fadec 03, flightworks pump 200A and a Multiplex 12 synth rx with a 2S2P A123 pack and it works great.
Many will have objections because i am running both the receiver/servos and the ecu from the same pack but
as i said i am using a 2S2P pack so if any cell is damaged the pack will still provide power.
I even tried it with a single 2S1P pack and it still works fine because the A123 cells have enough power to operate my turbine.
I also want to add that i also use a dc filter between the rx and the pack and another between the pack and the ecu
for dc power isolation purposes.
I don't think that it is a good idea to operate the pump, starter and fuel solenoid on anything more than 7,2V
if the before mentioned equipment use a 6V dc brushed motor especially since i have burned a starter and damaged a pump
in short time by using a 8 cell NiCd pack for testing.
In fact the rpm response and accuracy is much better now that i use a lower voltage because the pump
is more accurate. It has to do with the improved PWM resolution (it is a rather technical matter)
Before my pump would show a PWM reading of 700 at max thrust and now it is at 910 which provides more resolution
thus better rpm control.
Chris
I just want to let you all know that after considerable testing and data examination which took me almost two weeks
i now run my Boomerang intro with a Trefz tt66 (kj66, p80 variant) 21 lbs of thrust,
Fadec 03, flightworks pump 200A and a Multiplex 12 synth rx with a 2S2P A123 pack and it works great.
Many will have objections because i am running both the receiver/servos and the ecu from the same pack but
as i said i am using a 2S2P pack so if any cell is damaged the pack will still provide power.
I even tried it with a single 2S1P pack and it still works fine because the A123 cells have enough power to operate my turbine.
I also want to add that i also use a dc filter between the rx and the pack and another between the pack and the ecu
for dc power isolation purposes.
I don't think that it is a good idea to operate the pump, starter and fuel solenoid on anything more than 7,2V
if the before mentioned equipment use a 6V dc brushed motor especially since i have burned a starter and damaged a pump
in short time by using a 8 cell NiCd pack for testing.
In fact the rpm response and accuracy is much better now that i use a lower voltage because the pump
is more accurate. It has to do with the improved PWM resolution (it is a rather technical matter)
Before my pump would show a PWM reading of 700 at max thrust and now it is at 910 which provides more resolution
thus better rpm control.
Chris
