Hi

It would appear from reading this forum that it is possible to configure the ECU (v5.1) to operate with the voltage of an A123 pack, I am using a 4200mAh 2s2p pack on a P180, the batteries nominal voltage is 6.6v which is a little low for the 6 cell nicad pack setting.

Any info much appreciated.

Thanks

Phil.

Hi Phil,

I have never heard of a 2 cell 123 working with a JetCat ECU. Especially a P-180.

Does it start?

As to the voltage setting, it only affects any low voltage indications and alarms, which in my experience no one uses much anyway.

Regards,

Hi Matt

Well thats interesting..yes it does start!! it is a couple of years old and as such had one of the early ceramic kerostart plugs, but only recently got around to getting it flying.

After 8 or so starts (setting up etc) and 3 flights we could no longer get it started as the plug had failed, had become ablated to a little stub from the original longish form, unrelated I guess to the issue of ECU voltage.

A certain well known battery supplier (bright yellow) are selling the 2s2p A123 config as an ECU pack.

A 6 cell nicad pack off charge at 7.2 volts is not so different to the A123 2s config.

I have noticed that the start rpm (approx from memory) is 3600rpm which lowish I believe.

Is it possible to use a 3cell LiPo pack with the jet cat ECU?

Any thoughts

Thanks

Phil.

Hi Phil,

Yes I just talked to Wilcox, and a 2 cell A123 is not recommended, the voltage is just too low for reliable operation. (I am amazed is started a kero start P-180!)

A 2 cell LiPo is a great choice. A 3 cell LiPo voltage is too high.

Regards,

Matt

Thanks for that info, you are not wrong had some trouble starting today, new kerostart and fully charged A123's, strange how first few starts were fine.

Ah well 2 cell LiPo or LiIo it is then.

One other question whilst I have your ear, what difference ( if any ) does max engine rpm make to exhaust gas velocity and model speed, or is it just a question of an excess of thrust over drag that will determine model speed.

Just realised that is not really a jetcat question per say more of general aerodynamic one

Thanks any way

Phil.