Magic Pie V5 rear motor question.

[Tommycat]

Does anyone happen to know what the total capacitance, in microfarads, of all capacitors installed in it's controller.


Best regards,

T.C.

[Bikemad]

Hi T.C. andto the forum.

There are two large capacitors wired directly across the controller's battery supply which are both marked 80V 470uF.

In addition to these, there are a couple of smaller cylindrical capacitors 25V 220uF and 63V 47uF which I presume are for smoothing lower voltage circuits used for switching the MOSFETs and powering the Hall sensors etc..

I am unable to see whether there are any surface mounted capacitors soldered directly to the the PCB.

Alan
 

[Tommycat]

Awesome Alan! That's exactly what I was looking for. Thank you!

The reason I needed to know is I plan on installing one of those new (new to me...) Solid State Relays to separate the battery from my controller. It has a really neat lighted remote "on" button. But according to this site... HERE      you would need to install a pre-charge resistor circuit if the capacitance is over 1500uf. The information you provided adds up to 1207uf...great. Now my Bottle Battery 52v 11.5ah, has an on/off switch, but I would like to keep it on the bike whilst charging. (the battery switched needs to be "on" ) Also I think it would add a bit to safety and security.

I see where you have discussed power switch issues in the past, using double poled contacts to spread the amperage current. And even adding the pre-charge resistor and button. I would like to know your thoughts on this option.

Hey, and another quick question if I may... What are the torque specifications for the Pie's axle nuts?

Thanks again,

T.C.

[Bikemad]

Hey, and another quick question if I may... What are the torque specifications for the Pie's axle nuts?

Unfortunately, there are no actual torque figures available for the axle nuts, but you might want to check out this post for some useful information.

Alan
 

[Tommycat]

Thanks again! Much better than the books...   "tighten strongly"   

Any experience with the afore mentioned solid state relay switch?

[Bikemad]

I have not yet tried any solid state relays or switches, but I did purchase some IRFB4110 MOSFETs last year with the intent of making an automatic precharge unit as described in this post on Endless-Sphere.

Needless to say, I have not had chance to play with them yet. 

The SPS SafetyPowerSwitch unit that you previously mentioned appears to be a good (albeit somewhat pricey) unit.

I was hoping to make a similar unit that would hopefully fit inside the end cover my 48V GM battery to take the load off the mechanical key switch contacts, but until I have chance to build and test an external version, I'm not really sure how much heat will be generated when high current loads pass through the MOSFETs.

Alan
 

[Tommycat]

The SPS SafetyPowerSwitch unit that you previously mentioned appears to be a good (albeit somewhat pricey) unit.

I was hoping to make a similar unit that would hopefully fit inside the end cover my 48V GM battery to take the load off the mechanical key switch contacts.

Alan

Well worth the price IMO...  HERE.



Got it to fit in the end of my bottle pack...barely.  Just trying the fit.