[GreenKeys] Fusing Requirements for Loop Model 26

[Peter Gottlieb]

Two things. 

One, there is no surge current, this is an inductive circuit. 

Two, while a fuse is designed to carry rated current indefinitely, it is good engineering practice to not plan on running a fuse at greater than 80% of its rating (simplified version), so if you are going to fuse, and I’m not convinced it’s necessary, go with at least the 125 mA one. 


Peter

> On Sep 18, 2019, at 10:47 PM, Jim Cooper <jim.w2jc at gmail.com> wrote:
> 
>> On 18 Sep 2019 at 21:44, Zach Zarzycki wrote:
>> 
>> I'm going to be setting up my model
>> 26 with a laptop power supply, eBay
>> boost converter (boost to 97v)
>> resistor for my loop supply (60mA) and
>> the usb/tty board (Thanks
>> Jordan!) I'm trying to find a good
>> supply of the 63mA dc fuses to run
>> this, 
> 
> I think if you ever, ever found a 63mA DC fuse
> it would blow on the first mark transition, due 
> to surge current ...   I'm sure an 1/8 A fuse would 
> do just fine, maybe even a 1/4 A ...  the selector 
> magnets are a lot more forgiving than transistors !! 
> 
> w2jc
> 
> 
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