Using UK 13amp plug appliance wire to connect controller to battery?

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
My assisted range from the 6ah set up is only in PAS 1 with a KT 22a S09S, I'm only drawing 2.5a current (so really getting about 5.2ah from the pack) as I have dialled the power down to 19a and PAS 1 is frugal at only giving 13% current. Plenty for my flat terrain use.
 

afia2k8

Pedelecer
Dec 14, 2021
28
2
My assisted range from the 6ah set up is only in PAS 1 with a KT 22a S09S, I'm only drawing 2.5a current (so really getting about 5.2ah from the pack) as I have dialled the power down to 19a and PAS 1 is frugal at only giving 13% current. Plenty for my flat terrain use.
I see. Will have to just see once i've put everything together then.
Btw, do I need to buy a torque arm? The seller says i dont need one because the akm74sx 250w front hub motor is low powered but thought i should get one anyway just in case. Do I need a torque arm on both sides of the fork? Many thanks
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
From the graph one is likely to get approx. 35 mins use before the cut out occurs.
As was mentioned the pack BMS doesn't use a BMS so you will rely on the controller at 30v, going that deep will likely stress and age the cells quicker. I reckon you might get a good year out of them
 

afia2k8

Pedelecer
Dec 14, 2021
28
2
From the graph one is likely to get approx. 35 mins use before the cut out occurs.
As was mentioned the pack BMS doesn't use a BMS so you will rely on the controller at 30v, going that deep will likely stress and age the cells quicker. I reckon you might get a good year out of them
Does that mean 35mins continuous use? What does it signify?
I see. Will see if I can adjust the controller to cut off at 32v.
I managed to get the battery (18v4ah) at £17 each, so £34 for 20 cells - so a year of use should be ok. I will probably use light PAS most of the time, apart from the hills where it will be the highest PAS setting.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
One can't use TA's afaict as the axle is 10mm dia with only the very inner part having shoulders to sit in the drop outs, the motor cable exit is the same as my Bafang G370 and one can't fit a TA. Mine is fitted in cromoly forks.
 

afia2k8

Pedelecer
Dec 14, 2021
28
2
One can't use TA's afaict as the axle is 10mm dia with only the very inner part having shoulders to sit in the drop outs, the motor cable exit is the same as my Bafang G370 and one can't fit a TA. Mine is fitted in cromoly forks.
The Brompton swytch kit comes with a Torque arm so I'll be buying that or similar (needs some dremelling to fit properly. Just not sure if I needed one. If I do does it have to be on both sides of the fork or just one?

That's a good point. If I wanted to make my Brompton lighter in the future and put a titanium fork, will that be ok with a front hub motor?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
35mins continuous use on throttle.
The 74sx has a 12.6 internal gear ration so one should be able to pedal above any cut off speed if set low enough to eke out the range.
I set my cut off to 22km/h as the hub pedals nicely with no assist, just nice to have the acceleration when starting off in traffic or at junctions. So my assist range is greatly extended and means I am not 100% reliant on assistance.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
Ok so if a a TA is supplied then the axle must have opposing flat faces, one should suffice.
 

matthewslack

Esteemed Pedelecer
Nov 26, 2021
1,855
1,342
I've walked past those batteries so many times in Lidl, very interested to hear how it goes, both range and how long they last.

Nealh's wattmeter suggestion would help with not running the batteries flat, as once you know max Wh you can get, you can stop sooner next time!
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
The only issue with the watt meters is they aren't WP and if one wants to see the screen often needs wiring to be seen, when I used them I simply had one inline in a bag with the battery.
 

afia2k8

Pedelecer
Dec 14, 2021
28
2
35mins continuous use on throttle.
The 74sx has a 12.6 internal gear ration so one should be able to pedal above any cut off speed if set low enough to eke out the range.
I set my cut off to 22km/h as the hub pedals nicely with no assist, just nice to have the acceleration when starting off in traffic or at junctions. So my assist range is greatly extended and means I am not 100% reliant on assistance.
That's my plan too. It's mostly just for the hills. Here's pictures of the torque arm others have used with the swytch. Not sure if they used 2.

I'll be getting a thin KT LCD4 with the kit. Will see if I can set speed cut off and low voltage cut off on it.


I've walked past those batteries so many times in Lidl, very interested to hear how it goes, both range and how long they last.

Nealh's wattmeter suggestion would help with not running the batteries flat, as once you know max Wh you can get, you can stop sooner next time!
The batteries usually go for £25 but I managed to get it for £17 per 20v4ah. From this video looks like real capacity is about 3.7ah. I'm waiting for their parkside 20v8ah to arrive in the UK which should cost about £50-£60. Then I can put 2 in series for 40v8ah for £120. Comes with 3 years warranty as well. Video shows real capacity about 7.7ah

 

Attachments

  • Like
Reactions: matthewslack