Prewarm batteries is a MUST

[Thomas Hulbert]

Another item to warm the batteries could be a reptile tank heater. ( heating pad sort of item.

 

[Chilli]

Took about a month but I recieved a couple of the warmers from Hobbyking. I was surprised how warm they get. I was measuring 140 degrees F on high after only a few minutes. I can fit two 4S 5000 packs in one warmer. Should be fun to try out this fall.

 

[properchopper]

Good find. Have nine of these critters coming for the boyz & myself

 

[Robert Gillespie]

I haven't heard that. Anyone know if ROAR bans the practice? I know they have about six pages of Lipo rules in their book. All necessary safety precautions will be taken at the Elizabeth City SAW's. Packs will be warmed in Doug Smock's trailer...... I'll be parked at the other end of the lot ..... :lol:

ROAR has a rule on max volts. Two cell if over 8.4 volts you are DQ. Only at the nats and worlds and some big races.

 

[properchopper]

Just got a bunch of the HK warmers for me & the SoCal boyz. A pair of 4S 5000's fit. Will work great as a tortilla warmer. Yummm...

 

[gil sonsino]

Mike and Tony to protect the circuit and resistance of these bags do not exceed 2A .A customer of mine used his power suplly(12V 20A) with no amp regulator and fried the bag and batteries.I have a fuel power suply with voltage and amperage regulator but I'm also using this nice and cheap unit http://dx.com/p/24v-2a-regulated-switching-power-supply-100-240v-66678 Gill

 

[Chilli]

I think she is going to draw what ever amount of amps she wants to Gil. I put a Watts Up meter on her hooked up to my 47 amp computer server power supply for an hour and she was drawing 2.2 amps max at 12.5 volts. Voltage is probably the critical factor. My temperature readings were up a bit over the selections. At 105F she was in the low 120's.

 

[properchopper]

Mike and Tony to protect the circuit and resistance of these bags do not exceed 2A .A customer of mine used his power suplly(12V 20A) with no amp regulator and fried the bag and batteries.I have a fuel power suply with voltage and amperage regulator but I'm also using this nice and cheap unit http://dx.com/p/24v-2a-regulated-switching-power-supply-100-240v-66678 Gill

Uh Oh ! Gil, you got me worried ! I just recommended & obtained a bunch of these for the club. We mostly use 12V car or deep cycle batteries which clearly aren't amp-regulated. If a power supply is used, many of us use common 12V 20A hobby-grade units (like the red one in the picture).

Are we looking for trouble?

I will use the big monster power supply when I'm running 3 or four chargers at big events. Plus I have gathering dust the 11A unit in the picture which may (or may not) be regulated.

Now I'm afraid to hook up the warmer to my car battery. Help !

 

[Doug Smock]

Guys the load is your "amp regulator". :huh:

The bag is designed to pull 2a at 10 to 13 vdc.

It doesn't matter if you hook it up to a 12vdc 200a power supply it is still just going to pull it's 2a. unless there is a fault.

If you want to protect the bag and it's contents from a electrical fault, install a fuse inline if it's not there already.

Hopefully these bags have high temperature limits built in. If not that may be something you want to consider also.

Regards,

Doug

 

[properchopper]

Good advice, Sir. Since I'll be using this distribution thang, I'll just fuse its' channel with a 3A or 4A fuse.

 

[gil sonsino]

Tony ...Mike and Doug are right and after a closed inspection I figured out that the power supply of that guy is rated to 12 to 18v (20A) that must explain the problem.Yes my Reading temps with my infrared gauge are above the bag but nothing to worry about! With a 2A fuse you are good too.

regards

Gill

 

[properchopper]

Tony ...Mike and Doug are right and after a closed inspection I figured out that the power supply of that guy is rated to 12 to 18v (20A) that must explain the problem.Yes my Reading temps with my infrared gauge are above the bag but nothing to worry about! With a 2A fuse you are good too.

regards

Gill

Gill, thanks for double-checking.

 

[Chilli]

Might want to go with a 2.5 or 3 amp fuse since mine was drawing 2.2 amps when heating but I don't see the need for one. Just watch the input voltage.