Opti-power packs are here ;-)

[Mark_T]

Mark, mine are 5300's not 5000's so maybe that's the difference?

I don't think that is it as the 5300 would be bigger if anything, but since Andy has confirmed the production packs are smaller than the pre-production packs that would explain it.

[cjcj1949]

Chris

If you want to know more about C ratings go to our site and download the data you require there are a number of documents there. www.optifuel.co.uk double click OPTIPOWER on home page go to documents. More will go up over coming weeks.

OPTIPOWER™ – FACTS, MYTHS and RATINGS

This one will help but there are other on our site. best thing to do is ask one of our pilots to give you the packs after a 5 minute hard 3D set, they are barly warm to touch perhaps two or three degrees above the ambient.

Andy

I didn't see any info about what how C rating was defined. Perhaps I missed it. How do you work out from the test data? Perhaps I need one to evaluate. Suitable for a 450......

[Guest]

How is a C Rating Derived?

How is a C rating derived?

This is a question we get asked often but its’ of little practical relevance. The factory builds single cells as you are probably aware of given sizes, capacities and energy densities these single cells go to make packs as we use them.

To determine the C rating a single cell is connected to a discharge rig which comprises of a forced air tunnel with a given air velocity and the air is controlled to a standard temperature generally 25C. The cell is attached by very large copper conductors (very low resistance) and then the fully charged cell is discharged as fast as possible without the cell deforming or exploding. The C rating is then derived from the capacity discharged over time for single cell. THIS IS NOT A PACK RATING!

As an R&D exercise this has some relevance but we do not use cells in this way and a single cell that can do 50C in this condition is not the actual condition the PACK is used in. In a pack there could be one to five cells sandwiched between the outer ones so the inner cells get no cooling effects and in fact very often get hotter than the outer cells. The tabs between cells are not anything like as big as those on the test rig and the two outer cells have the silicon conductors attached for discharge and of course each cell has a balance wire added to it.

So in a flight pack the C rating is not really the best single cell C rating it’s the rating as a pack that’s of relevance. We spent a lot of time and money looking at this and testing.

The real measure of a good pack is how it delivers the power and holds the voltage during that period and does it get hot? This has much more to do with good cell construction and matched single cells than what their C rating is.

Proof of the pudding is try one and see, you will not be disappointed!

I trust this is helpful.

Andy

[Mark_T]

So in a flight pack the C rating is not really the best single cell C rating it’s the rating as a pack that’s of relevance. We spent a lot of time and money looking at this and testing.

Thanks for the details, all very helpful.

Just so I'm clear, are the ratings you decided to put on your packs the real 'pack rating' or the single cell rating?

[AcidDrink]

Where can I buy one or two of these? I am going to give them a try and see if they last for 200 cycles.

[Stuart]

As I read it Mark Optipower are rated as a pack rather than single cell I.e. the relevant figure in essence. I am sure Andy or one of the testers will confirm.

[Mark_T]

As I read it Mark Optipower are rated as a pack rather than single cell I.e. the relevant figure in essence. I am sure Andy or one of the testers will confirm.

That was my feeling as well, just wanted to be sure though.

Certainly a better way to do it if it is the case.

[Tim Procter]

Picked mine up today, Thanks Andy.

Busy fitting EC5's tonight.

Havent checked the weight difference against my current Turnigy's but certainly a lot lighter that's for sure.

[Guest]

It's a pack rating. The interesting thing is that in testing using the UK's best 3D pilots we cannot even get to half our rating!!

We have done 100's of hours in test now and so far things looking good. 200 cycles for sport flyers should be perfectly possible really hard 3D we know 100 cycles plus is possible and looking at the stats coming back from every flight probably way more but time will tell. The OPTIPACKS are certainly strong and we look forward to feedback. Pack life is also a function of good cell management, proper ESC and gearing plus of course proper charging. Charging correctly can double cell life and thats any suppliers cell!

This week Revolution have them in stock and Fast Lads will have them in stock. Soon we expect Midland, Skyline and many others to take them up as demand grows. We will have them at the BMFA Nats. Currently the cells are being flown at F3C Worlds by UK and France and have been flown at many UK events this season both heli and fixed wing. Our cells were also used by the UK F3A team in the USA worlds earlier this month.

These guys F3A and F3C have the pick of the bunch and slowly they are going OPTI!!

Andy

[ChrisB]

Will follow the reports from normal fliers with great interest.If the packs can walk the walk and last as many cycles as claimed they might just be viable over the current ones i use which are excellent.

[PeteStewardson]

Picked mine up today, Thanks Andy.

Busy fitting EC5's tonight.

Havent checked the weight difference against my current Turnigy's but certainly a lot lighter that's for sure.

Lucky B***er.

[Jamin_00]

Lucky B***er.

A mighty bit poorer this evening me thinks

[Kwickkwack]

well it looks as though the Logo will get a good hiding this weekend Tim

[Guest]

Pete,

He certainly is (all paid for however), I look forward to seeing the LOGO kicking arse this weekend!

Might even get my 450 out or my little Macko delta! TREX700 waiting for new ESC from Castle and 550 needs setup completing, 500 ready to rock and trusty 700N waiting to slurp up some more 20SLV.

Andy

[trillian]

Pete,

He certainly is (all paid for however), I look forward to seeing the LOGO kicking arse this weekend!

Might even get my 450 out or my little Macko delta! TREX700 waiting for new ESC from Castle and 550 needs setup completing, 500 ready to rock and trusty 700N waiting to slurp up some more 20SLV.

Andy

Do you have an Avro as well?