2s 20000mah Lipo receiver battery ?

[tigerman]

I see that HSD make a 20000 wingspan Cessna .It is powered by a 6s lipo but also you need a 2s 2000 mah lipo to power  the radio equipment .Would I have to charge the 2s 2000mah lipo up after every flight or will one charge do several flights. Be a pain if you have to charge up the 2s lipo after every flight .I am sure once you have a fully charge 2s lipo for the radio equipment that would last most off the days flying .I hope so 🤞I am not talking about  the  6s lipo you need to power the model .I know that will only last one flight

[Mike T]

One charge should last you all day.

[Eric Robson]

A 2s 2000 should last all flying session, I use 2000 4.8v batteries in my ic planes  and get a few sessions flying before recharge, I check them regularly through the  tranny when  flying. A lipo should last as long.

[simon barr]

Unless you are using a high voltage capable receiver and servos, make sure that you are running the 2s pack (7.4 volts) through some sort of voltage regulator to reduce the voltage down to a max of 6 volts, or else everything will fry.

[Martin McIntosh]

Why not try LiFe Rx packs? Much more reliable and safer and you would be surprised at how little recharging they take after a flying session. 1100 if you only have about six servos or 1800 if more (definitely NOT nanotech ones though).

[Frank Skilbeck]

I have similar on my 6s MR Hurricane, radio battery , 5 cell nimh in my case, lasts many flights.

[MattyB]

 

1 hour ago, tigerman said:

I see that HSD make a 20000 wingspan Cessna .It is powered by a 6s lipo but also you need a 2s 2000 mah lipo to power the radio equipment .Would I have to charge the 2s 2000mah lipo up after every flight or will one charge do several flights. Be a pain if you have to charge up the 2s lipo after every flight .I am sure once you have a fully charge 2s lipo for the radio equipment that would last most off the days flying .I hope so 🤞I am not talking about  the  6s lipo you need to power the model .I know that will only last one flight

 

After carefully reviewing the title of this thread and your first post, I think the "0" key on your keyboard may be broken... 😉

 

More seriously, back in the day we used to fly 4 servo slopers on a 500mah NiCad all day long. A 2S 2000 LiFe or Lipo will therefore last many many flights, certainly a days worth (as long as you remember to turn it off between flights). Looking at the spec of the model it appears there will be no need for a regulator as the servos are rated to 7.4V, though you could just as easily use a 4.8V or 6V Nimh pack too. It is quite nice to see that in a model liek this they are not using a BEC - I personally don't like integrated BECs on anything above 4S, and at 6S the weight penalty of the extra pack is not going to be as relevant anyway.

 

[Rocker]

28 minutes ago, MattyB said:

 

 

After carefully reviewing the title of this thread and your first post, I think the "0" key on your keyboard may be broken... 😉

 

More seriously, back in the day we used to fly 4 servo slopers on a 500mah NiCad all day long. A 2S 2000 LiFe or Lipo will therefore last many many flights, certainly a days worth (as long as you remember to turn it off between flights). Looking at the spec of the model it appears there will be no need for a regulator as the servos are rated to 7.4V, though you could just as easily use a 4.8V or 6V Nimh pack too. It is quite nice to see that in a model liek this they are not using a BEC - I personally don't like integrated BECs on anything above 4S, and at 6S the weight penalty of the extra pack is not going to be as relevant anyway.

 

 That would make life a lot easier for  me if I could use  6 volt nimh pack 

I have a load of 6 volt nimh receiver batteries 

[Cuban8]

1 hour ago, simon barr said:

Unless you are using a high voltage capable receiver and servos, make sure that you are running the 2s pack (7.4 volts) through some sort of voltage regulator to reduce the voltage down to a max of 6 volts, or else everything will fry.

Absolutely. Even if complete destruction of an over-volted system doesn't occur, you can get some weird things happening to some servos, while others don't seem to mind. A thorough check needed to make sure. I had some micro servos that were fine at 6V or a bit over, but would lose resolution terribly on a freshly charged 5 cell nimh pack nearer 7V. All fine if left for half an hour to settle down, but could potentially catch you out after a quick top up charge over the field if you forget.

Voltage regs are fine, but another potential point of failure added to the mix. Having said that, I've had a couple of these Regulator in use for a number of years and feel very confident in their reliability. I run mine from the four cell flight pack, but their specification quotes an input of 6 to 24V.

Edited June 6, 2023 by Cuban8

[MattyB]

3 hours ago, Rocker said:

 That would make life a lot easier for  me if I could use  6 volt nimh pack 

I have a load of 6 volt nimh receiver batteries 

You absolutely can, that is always an option with any RC system, irrelevant of brand (ignore the “you need a 5 cell pack for Spektrum cos of brownouts” posts, they hark back to a time when their earliest receiver would reboot at relatively high voltages, but that no longer happens with any RXs they’ve sold for the last 10 or so years).

Edited June 6, 2023 by MattyB

[MattyB]

3 hours ago, Cuban8 said:

Absolutely. Even if complete destruction of an over-volted system doesn't occur, you can get some weird things happening to some servos, while others don't seem to mind. A thorough check needed to make sure. I had some micro servos that were fine at 6V or a bit over, but would lose resolution terribly on a freshly charged 5 cell nimh pack nearer 7V. All fine if left for half an hour to settle down, but could potentially catch you out after a quick top up charge over the field if you forget.

Good advice in general, but the spec sheet on this model states unequivocally that the servos are designed for 7.4V…

 

[PeterF]

I have the HSD Me262, a 2000mAh 2S lipo will do multiple flights, the most I have done is 6 with plenty left.

 

Despite all the discussion above by posters without direct experience of HSD models, the servos are HV and I have not fitted a voltage regulator. In fact, if you fit a voltage regulator with HV setvos then you will reduce the available power of the servos. This may not be so much of an issue for the Cessna, but for a large twin 90mm EDF I have not risked compromising servo power. The only proviso is to make sure your receiver is good for HV to 8.4V.

[Rocker]

13 hours ago, PeterF said:

I have the HSD Me262, a 2000mAh 2S lipo will do multiple flights, the most I have done is 6 with plenty left.

 

Despite all the discussion above by posters without direct experience of HSD models, the servos are HV and I have not fitted a voltage regulator. In fact, if you fit a voltage regulator with HV setvos then you will reduce the available power of the servos. This may not be so much of an issue for the Cessna, but for a large twin 90mm EDF I have not risked compromising servo power. The only proviso is to make sure your receiver is good for HV to 8.4V.

 

[Rocker]

Thanks Peter I just rang Wheelspin Models where I have order the HSD Cessna and they confirmed that the 2s 2200mah lipo will be fine for the Cessna 

[Cuban8]

 A problem regarding higher voltage batteries that in actual fact never existed with the OP's model, considering its servo specifications. I'm not familiar with the exact model so have taken a look at the operators manual for it. Clearly, not a cheap and cheerful bit of kit fitted with equally cheap and cheerful servos.

Wonderful bits of Chinglish throughout the manual - my favourite after "ball buckles" is.........."Don't fly in the Arctic" whilst showing a map of Antarctica. Geography not their strong point either.

Should be a nice model though. Good vid here........

Cessna

Edited June 7, 2023 by Cuban8

[MattyB]

54 minutes ago, Cuban8 said:

 A problem regarding higher voltage batteries that in actual fact never existed with the OP's model, considering its servo specifications. I'm not familiar with the exact model so have taken a look at the operators manual for it. Clearly, not a cheap and cheerful bit of kit fitted with equally cheap and cheerful servos.

 

This discussion of HV servos has triggered a few questions for me, but rather than taking this thread too far OT I've started a new one instead...

 

 

Edited June 7, 2023 by MattyB

[PeterF]

As a follow up to this today, I flew my HSD Jets Me262 which has 2 packs of 2S 2200mAh packs for the Rx supply. The Me262 like the Cessna and most of the HSD Jets has what they call an MFC, multi function control into which you attach the Rx battery pack(s) and from this the power goes to your servos, retracts, lights, ESCs etc and the input comes from an SBUS signal from your receiver. I noticed on my receiver telemetry that I had 7.4V even with new Rx battery packs in and it stayed at 7.4V during the 6 flights I made. So the HSD Jets MFC device must have a voltage regulator set at 7.4V, which then powers the on board kit which is rated for 7.4V and your receiver.