I use 2 fuses soldered together in parallel to cut the resistance in half. Thanks goes to CraigHB for that tip and to breaktru for his post on using an external fuse in his mod that got me started in using a fuse in my mods. Maybe nothing is 100% safe, but external fuse adds a safety and comfort zone when using high drain lipo batts.
mouser.com has the best price on the fuse I use. Digikey and others also have these fuses, but more pricey.
16R300GU
But how does the paralleling affect the Hold Current and Trip rating? It should double both as far as I can tell. But there are some problems when paralleling like that. The PTCs will have to identical as will have to be the leg length, as the current will always take the path of least resistance, creating some minor imbalance.
There are a lot of other factors I've seen but they are in regards to voltages so I don't know if apply here.
...even when the energy is perfectly shared between 2 fuses in parallel each fuse will see more energy that it would have to withstand when tested alone.
The breaking capacity of 2 fuses in parallel can be less that the capacity of one fuse
With all that said
. The two listed fuses in parallel, I'm assuming, would have a new Hold of 6A, a Trip of 10.2A and a resistance of .049Ω. Is that your take on the new specs?
Wouldn't it be a lot easier to just go with one and just avoid any parallel mumbo jumbo?
16R600GU Littelfuse | Mouser
6A/10.2A and even lower resistance, .028Ω.
One other thing I wonder about is the 6A hold when used with the DNA20. According to the sheet, for max thrust it calls for 7A. Can a 6A/10.2A PTC handle that? Sure, but once past it's hold rating it's resistance starts to increase.
Well we could increase the Hold to 7A while lowering the resistance even more to .02Ω. Unfortunaly the trip rises to 11.9A.
16R700GMR Littelfuse | Mouser
Wish RocketMan was around to chime in.
Oh well, food for thought.
