Dead Magic Pie or can I resuscitate it????

[robertozm]

in the cycle analyst, whats the minimum volts recorded ? ( I think third screen to the left, min volts, max amps)

regards

I think I change that when I first installed the cycle analyst, but now it says 15 volts, but I am not sure if the voltage has drop that low

Tomorrow morning I will go for a ride keeping an eye on the screen of the minimum voltage, so I can tell you more accuaretly.
Roberto

[DirtyGinge]

Hi roberto

The cycle analyst will record it on one of the screens, usually if the battery is cutting out, it will record the last voltage before the battery cuts....besides, you need to look forward , you might hit some drunk ginger cyclyst

[robertozm]

Hi everyone.
This morning I made a few changes.  First thing I change was the BMS, and the problem persisted.
Then I change the Battery (called A) for the Spare one (called B).  Since the B battery has not the double voltage output 24-36, I used the A to feed the relay, and......VOILA It workss!!! 
Everything  seemed alright, but (as always there is a BUT ) the cycle analist started to give me strange data as -2000w, -39volts..., and when I had to stop at an intersection, everything went dead again.  Key off, key on and live again!!!  Then I started to ride uphill, full throttle, braking hard, starting hard, and if the wheel stops completely, again everthing turned off.  Key off, key on and everything started again. But as long as the wheel didn´t stop completely, it seems to work.
Since I went for a test ride, I had wires provisionaly connected and the lid of my aluminium box (were the battery, relay, Bms, and connections are hosted) and a thread of rope holding the battery from falling, so I went back home to make the connections right and to close the box.
Looking for some conectors I found a voltage regulator L7864CV I didnt remember I bought long time ago for a lights "project).  So instead of having the battery A in the pannieres with to long wires... I decided to install this voltage regulator, but in order to do that I had to make a few changes in the connections I had.  And in the emotional state of joy I made a mistake and feed the relay with 36volt and it is burnt

So now I can´t do anything until Monday when I hope I will find another relay or place an order for it, and I still have the doubts about if the stopping was a result of faulty connection or anything else...

Does anyone have an idea why the cycle analyst did gave me negative values and so high??

Roberto
 

[robertozm]

Hi guys!!
It has been a hard working week, and with not very good results.  I opened the relay, and nothing seemed burnt, I tried it for about 20 times and it worked, but what seemed to be broken was the voltage regulator, so instead I installed a resistance (the guy at the electronic shop made the calculations) and when measured the voltage is 24volt.

I had a lot of connectors inside the box and a few of them didn´t look very well so I decided to replace them for a new conector, so instead of the typical GoldenMotor Black, Blue, Green, Yellow, Maroon, and White, I have a 6 pin connector.  Obviously, I have renounce to a few functions such us pedelec, or rear and front light, but I do have cruise, throttle,and brakes.  I took the opportunity to cut the length of a few wires in order to make them to my needs.

Another important improvement was to add the battery nº2 to the system.  So I placed diodes (big ones) in each phase, and they "add" to the system before the relay swicht.  I replace the fuse holder of each battery for a bigger one (10AWG) and new 30amp fuse (car type).

Everything was "repacked" inside the box and yesterday I went for a ride for almos 25 minutes/10km and 4.35amp consumed until everything went dead again.  
While riding I was looking very closely to the voltage and It never dropped of 34 volts (I had both batteries connected), 32.92 amp maximum, a maximum of 750 wat going uphill at 12km/h and the consumption was high, nearly 1 amp every km but I was not pedalling at all .  The maximum velocity was 40 km/h going dowhill, and max regen 0.20 amp I think it was 200wat, but I don't really remember that data.

As I said, evertything went dead when I was going up in a very mild uphill.  I touch the hub and was mildly warm.  I waited a few seconds and turned the key, the cycle analyst flashed a second and then dead, I tried again but this time no flashing, no nothing .   I waited for about 2-3 minutes, but nothing.  
I had to pedal back home, where I opened the box, and the Bms was not hot, the resistance was not really hot, BUT the relay was hot.  I tried to make the relay work without the keyswicth but it works ramdomly. I look and the voltage was correct 24volt, so I suppose the relay is the weak point, but it is nearly new, I opened and everything seams right, so I don't know if this is my problem or is anything else..

I am thinking to change this electromecanic relay for a solid state one.   I am not sure if buying an 60Amps or a 80amp like this one
 http://cgi.ebay.com/Solid-State-Relay-SSR-DC-DC-80A-3-32VDC-5-220VDC-/370495498474?pt=LH_DefaultDomain_0&hash=item564340a8ea  
What do you think about this change and which one do you recomend?

Can anyone have an idea what might be wrong??
Thanks.

[rollin76]

Hello is it this wire that need switch inline and run to battery instead of being hooked to main battery feed as is?

[robertozm]

Hello is it this wire that need switch inline and run to battery instead of being hooked to main battery feed as is?

Thanks Rollin76.  If you check out a few replys back, BikeMad told me that , but now I have a Magic Pie with Internal controller, and I can not have access to that wire.

Thanks anyway.

[robertozm]

Hi again:
I have just come back (Walking-Pedalling) with my dead bike.  Last night I left the batteries charging and disconectted them at about 1pm today (I think fully charge) and went for a ride.  I wachted the cycle analyst readings and 22.74amp was the maximum amperage going uphill without pedalling and 35.2volts was the minimum voltage I saw.

For 2o minutes was running very well but suddenly and at 36.1volt and 19 amp everything shut down again.  Today I left with the box open so I could check out if anything was hot, so I can assure the Bms was not hot at all, the keyswicht wasnt either, the relay was a little bit hot but I could touch it with my finger tips without any problem, but the hub was really hot.  So I waited for about 25 minutes in the shade and try to "ignite" it again, and as always , sometime the cycle analyts flash for 1 sec and thats it.

I was wondering... if the hub motor was as hot to cut off, the motor would has stop, but the cycle analist should be alive isnt it???  So if not it is because there is no current going though the relay and hence to the cycle analyst, therefore my problem is with the relay???

Please guys I need your help.  Could you please tell me what you think about the above, and if you agree with the relay, which relay do you recomend of the one I show 2 replies above??

Roberto

[DirtyGinge]

would it be better to remove the relay to take a potential problem out of the loop ?

[robertozm]

would it be better to remove the relay to take a potential problem out of the loop ?

But I need it in order not to burn the key swicth.  How do I turn off everything???

[Bikemad]

Roberto, it definitely appears to be a voltage supply problem, not a motor cutting out problem.

If both batteries have their own BMS and the diodes fitted for the second pack are facing the right way, it should rule out a faulty BMS causing the problem, unless the BMS on the second battery also suffers from the identical problem.

You really need to be able to test for battery voltage being supplied to the relay when the fault occurs to be able to rule out the batteries.

That solid state relay is not ideal for this application, as they generate heat during use and will also continually draw a small amount of current from the battery when switched off.
Although 2mA is not very much, it will still drain 1.5Ah per month out of your battery if left connected but unused over the winter months etc.

Check out this post for further information on Solid State Relays.

If you have enough room to fit one of these inside your box:



these battery isolator switches are much cheaper than a solid state relay, don't require any current to operate and can cope with at least 100Amps. These switches are normally available at most car or marine spares specialists.

Another good alternative is a latching relay:


                Click for more details.               
This 60Amp latching relay has the big advantage of only drawing a small amount of power for less than a second while the relay is switching from the "OFF to ON" or "ON to OFF" state.

The relays pictured above seem to be the double coil version (three pins) which operate slightly differently to the single coil version shown in the circuit below, the single pin would connect to battery negative through the resistor and momentarily switching battery voltage to each of the two other pins will turn the relay on or off dependant upon which pin is being fed with battery voltage.

You could use a momentary (ON) OFF (ON) (springs back to centre Off position) rocker or toggle switch or even two separate momentary push to make buttons. If using two separate buttons, I would recommend using a separate resistor on each of the 36V supplies to the button switches and connect the single pin on the relay directly to battery negative. This would prevent the single resistor from being overloaded if both buttons were pressed simultaneously.

Here is Leslie's diagram showing how the single coil (two pins) latching relay can be switched:



Hope this helps,

Alan
 

[Cornelius]

I'd go for the battery isolator switch; those are designed for high DC amperage and costs little, and are also available in 300A versions with little extra cost. They are designed to switch on/off main power in large caravans and boats...

I still think it's a bad idea with your relay tapping part of the battery cells... (Maybe it is really that which are at the base of your problem? the bms freaking out a bit because of uneven load of the cells?) (I am well versed in solar/wind power, and tapping for example 12V from a 24V battery bank are a big no-no in those communitys. )

[robertozm]

Roberto, it definitely appears to be a voltage supply problem, not a motor cutting out problem.

If both batteries have their own BMS and the diodes fitted for the second pack are facing the right way, it should rule out a faulty BMS causing the problem, unless the BMS on the second battery also suffers from the identical problem.

You really need to be able to test for battery voltage being supplied to the relay when the fault occurs to be able to rule out the batteries.

That solid state relay is not ideal for this application, as they generate heat during use and will also continually draw a small amount of current from the battery when switched off.
Although 2mA is not very much, it will still drain 1.5Ah per month out of your battery if left connected but unused over the winter months etc.

Check out this post for further information on Solid State Relays.

If you have enough room to fit one of these inside your box:

these battery isolator switches are much cheaper than a solid state relay, don't require any current to operate and can cope with at least 100Amps. These switches are normally available at most car or marine spares specialists.

Another good alternative is a latching relay:

This 60Amp latching relay has the big advantage of only drawing a small amount of power for less than a second while the relay is switching from the "OFF to ON" or "ON to OFF" state.

The relays pictured above seem to be the double coil version (three pins) which operate slightly differently to the single coil version shown in the circuit below, the single pin would connect to battery negative through the resistor and momentarily switching battery voltage to each of the two other pins will turn the relay on or off dependant upon which pin is being fed with battery voltage.

You could use a momentary (ON) OFF (ON) (springs back to centre Off position) rocker or toggle switch or even two separate momentary push to make buttons. If using two separate buttons, I would recommend using a separate resistor on each of the 36V supplies to the button switches and connect the single pin on the relay directly to battery negative. This would prevent the single resistor from being overloaded if both buttons were pressed simultaneously.

Here is Leslie's diagram showing how the single coil (two pins) latching relay can be switched:

Hope this helps,

Alan
 

Hi Alan:
Thanks again for the time you take in your research and detailed answers.

Actually I don't have enough room for the battery isolator switches, and if I want to fit it I will have to do mayor reforms such us new holes, and cover the old ones etc...

About the latching relay, I have read 3 times your text but I do have lack of electronical knowlegde, so I don't even know how to start telling you what I don't understand

So I think I will keep on with my solid state relay in which I do have a big doubt.  You talk about continuous draw of current but the way I have it configured the drawn of current from the relay will only occur while using the bike because when the key switch is off no current is going to the relay, isn´t it??  See wiring diagram attached.
 
About measuring the voltage, when it is working (plug it to the relay) I can read 24.2volt.  When disconected of the relay 39volt (With no load the resistance doesnt lower the voltage, the guy at the electronic components shop told me...)

Which one do you think will fit better the 40, 60 or 80amp... The difference in price is not much and I think the 80amp will work with less stress (ie. temperature) then the others isnt´t it??  Since the box is made of aluminium I will take the protective foam of the inside where I will install the SSrelay with some thermal paste to improve the heat transfer and I think this will be enough, don't you think so?
http://cgi.ebay.com/Solid-State-Relay-SSR-DC-DC-40A-3-32VDC-5-220VDC-/250793127324?pt=LH_DefaultDomain_0&hash=item3a646f6d9c
http://cgi.ebay.com/Solid-State-Relay-SSR-DC-DC-60A-3-32VDC-5-220VDC-/390300012140?pt=LH_DefaultDomain_0&hash=item5adfb18e6c
http://cgi.ebay.com/Solid-State-Relay-SSR-DC-DC-80A-3-32VDC-5-220VDC-/370495498474?pt=LH_DefaultDomain_0&hash=item564340a8ea

Again thanks for your time;)
Roberto

[Bikemad]

I'll get back to this later as I'm just off to work now, but the diodes in your diagram do not allow the second battery to give any assistance at all.

Alan
 

[robertozm]

I'd go for the battery isolator switch; those are designed for high DC amperage and costs little, and are also available in 300A versions with little extra cost. They are designed to switch on/off main power in large caravans and boats...

I still think it's a bad idea with your relay tapping part of the battery cells... (Maybe it is really that which are at the base of your problem? the bms freaking out a bit because of uneven load of the cells?) (I am well versed in solar/wind power, and tapping for example 12V from a 24V battery bank are a big no-no in those communitys. )

Hi Cornelius:
I already undid that.  That is why now I feed the resistance with 36volt, and get 24volt.   I lose energy in unneeded heat but since I first tried with a voltage regulator that apparently was broken the guy at the electronic shop suggested to do it this way.  I also look the voltage in each cell (without load) and there were  a difference of 0.1volt in 1 pack of cells, so I suppouse they are all right.


Another reason because I want to install the Solid Stat relay  ( http://cgi.ebay.com/Solid-State-Relay-SSR-DC-DC-80A-3-32VDC-5-220VDC-/370495498474?pt=LH_DefaultDomain_0&hash=item564340a8ea ) is because I don't have to do anything with the supply since the cope with 3 to 32volt (My battery is giving 40volt when completely charge and I hope those +8volt wont burnt the relay)

I have everything configured for the relays and changing that... uffffff I really prefer not to do it.

Thanks

[robertozm]

I'll get back to this later as I'm just off to work now, but the diodes in your diagram do not allow the second battery to give any assistance at all.

Alan
 

You are right.  I think I screw them in the wrong way....
My electrical and electronical knowledge is going backwards.  One step forward, two bacwards....