12v charger adaptor supply

[fly boy3]

I have just recieved from HK an IMAX b6 charger. I would like to supply charger with a 240v/12v adaptor. How do I specify size of male plug or are they standered. Cheers

[Geoff S]

4mm is the most common size for single pole connectors. What 12 source are you using for 12V? Whatever it is it will need to be able to supply at least 10 amps, preferably more.

Geoff

[flight1]

Well if it is the imax b6 genuine charger they sell it is rated at 50watts 5amps , but it comes with croc clips on the input leads for which to connect to a 12v battery (input max 20volt dc min 11v dc).

What is going to be your input source ?

[fly boy3]

Hi all, at the moment as you say I am using a 12 v battery and crocodile clips supplied, but I would like to use a mains adaptor. Perhaps wrong thing to do ? Cheers

[John Rudd]

Why not just purchase a suitable charger for your battery, connect it up when in use to prevent over discharge..?

[Robert Cracknell]

See EBay item number 321943081214...

[Denis Watkins]

Try one of these FB, within B6 tollerance

**LINK**

[flight1]

If you want a project you can convert a pc power supply as i have works well and this latest one i have has been going at least 7 years more proberly. also sever power supplies are good too better durability to , search on here plenty of post of how to.

coor just seen that post above thats good for 8 amps but converting a server power supply will give more wattage for less money

[Martin McIntosh]

I was once fortunate enough to acquire several 12V/5A power supplies intended for use on small monitors but these tend to be silly money from places like Maplin. If you are serious about electric model charging then the Rapid 85-1706 takes some beating.

[gangster]

Those little coaxial dc plugs are far from standard. I would have referred you to Maplin to see just how many there are, mae a bit late for that. I have a charger which claims to be an IMAX B6 for field charging it must be a clone but has done sterling service over the last couple of years. I did however manage to melt the input socket on one occaission. Charging a Lipo at 5 amps would have required an input current of considerably higher current I am guessing at least 8A. A very large current for such a tiny connector. I hard wired the input lead after that. People have mentioned having croc leads are they hard wired or do they go into the unit via the little plug. My Core charger used the same sockets but is always used on mains via its internal power supply. An ill fitting or corroded plug would certainly get hot

I wonder if anyone else has had melt down, fortunately I fuse my input leads there is a bit of energy in a 110Ah leisure battery

[gangster]

I have just checked the spec of my “clone” iMac B6. It quotes 80 Watts 6A charge. That in my book would let you charge a 4S at 5 amps. But beware it will need a hell of a lot bigger 12volt power supply than 5 amps to deliver the required input power

[Robert Welford]

My Ripmax 20A power supply recently died, so I bought a server power supply - one of these: HP 321632-001 Proliant DL380 G4 575W for £15 on eBay.

I wired it to give 2 outputs to give at least 40A. It is the business - high quality. Instructions how to modify it can be found on the interweb.

[Martin McIntosh]

My Eco 6-10 has hard wired i/p clips and is rated at 200W but I believe that they make smoke at about a third of that. Even though I use some high capacity batteries I rarely charge at above 1A so a 5A power supply is quite good enough.

Old PC power units are often used and will supply lots of Watts.

Those dc barrel connectors usually have a 2.1mm centre but some can be 2.5. CPC is a good cheap source of them but the quality is not great and the plating on the centre part can make soldering a bit tricky.

[MaL]

DC coaxial power connectors are rated at 12V @ 5A...Pushing them more than that is asking for trouble, especially in a dirty environment

[Kevin Wilson]

Refering to the original question.

If you are referring to the coaxial dc input socket such as commonly used for transmitter charging connectors.

These are specified by outer then inner dimmensions. The outer is commonly 5.5mm but the inner varies, 2.1mm and 2.5mm are the ones I see mostly. These would be specified 5.5x2.1 or 5.5x2.5 respectively.

Measuring the plug is easy, using a caliper on the outside diameter and a drill bit as a plug gauge on the bore.

The sockets I usually measure by trying first a 5.5x2.1 plug then a 5.5x2.5 plug.

As has been mentioned, we are pushing these connectors hard so the correct size is essential. You can get away trickle charging a tx with the wrong connector, they will often make sufficient contact, but a recipe for disaster when drawing higher current.

[fly boy3]

Nice one Kevin, that's the answer I needed. Thanks to all who have suggested suitable power supplies, your info has been very informative. Cheers

[Robert Welford]

Someone is offering converted server Psu's on BMFA Classifieds.

If interested: **LINK**

[Dave from the future]

I'm running an Imax B6 clone charger from a 6A Toshiba laptop power supply. One other thing I have found with the DC coax plugs is that the length varies - I have a digital radio I'm having trouble getting to work because the replacement adaptors all have shorter plugs than the original one did.

[Martin McIntosh]

I believe that these are either 10 or 14mm long. Just bought some more 14mm from CPC because I was also having problems with the shorter ones. Made no difference to my charger connection which turned out to simply be a dirty socket.