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Discussion Starter · #1 ·
So I have been working on this for a little while. I have my wiring diagram of my conversion I am getting ready to start. I am using a '96 Kawasaki zx600 rolling frame as the chassis and a lot of bits from an electric car I was given. Most of my components are in the wiring diagram as far as what components I am using.

I took my controllers wiring diagram and combined it with my BMS diagram they give in the manual.

Some of the questions I have:
  • Is this looking correct and would it work?
  • What do I need to change or include if I forgotten anything?
  • What size wire should I need for the different components?
  • What connectors should I get and where should I put them?

I am getting ready to start making my battery bank of LiFePo4 a123 26650. I am making a 32S 15P system.

 

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not an expert on this, so take my advice with a grain of salt.

the wire from B+ to the current sensor, on the left side of the drawing, is that a HV-cable or a signal cable?
no fuse on the DC-DC converter?
the control module on the top left, does that handle HV? i see that it has a wire connected to the motor output from the inverter/motor controller.

what is the thing on the top right? throttle?
 

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Reading Howie's comments and referring to the drawing, I notice that there are multiple lines which are colour-coded yellow meaning "LV POSITIVE SIGNAL +", but are connected directly to B+ (which is high voltage).

In the example on page 6 of the EVMS manual the fuse shown just above and to the left of the EVMS supplies the DC-to-DC from the battery; in this version the B+ to DC-to-DC takes a different route and this fuse makes no sense.

I don't understand the wiring of the current sensor. It is intended to measure the current out of or into the battery, and communicate that information via CAN to the EVMS; the CAN wiring is shown (also connecting to the BMS slaves), but the HV current connections are not in the HV current path. The example on page 6 of the EVMS manual shows the current sensor properly in series between the battery and everything else; the modified version moves the HV current path but leaves the current sensor in the same place, measuring nothing.

Some lines change colour irrationally in this diagram, confusing the meaning. For instance, the correct connection of B- to EVMS pin 8 changes from the intended black (HV NEGATIVE) to blue (which is supposed to be BMS SIGNAL WIRE).
It would probably make sense to check each wire to see if it does what it is intended to do and is shown appropriately. Obviously HV+ and LV+ wires would never be connected together, so when you see that it tells you that either the connection is wrong of the colour coding is wrong.
 

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Discussion Starter · #5 ·
Reading Howie's comments and referring to the drawing, I notice that there are multiple lines which are colour-coded yellow meaning "LV POSITIVE SIGNAL +", but are connected directly to B+ (which is high voltage).

In the example on page 6 of the EVMS manual the fuse shown just above and to the left of the EVMS supplies the DC-to-DC from the battery; in this version the B+ to DC-to-DC takes a different route and this fuse makes no sense.

I don't understand the wiring of the current sensor. It is intended to measure the current out of or into the battery, and communicate that information via CAN to the EVMS; the CAN wiring is shown (also connecting to the BMS slaves), but the HV current connections are not in the HV current path. The example on page 6 of the EVMS manual shows the current sensor properly in series between the battery and everything else; the modified version moves the HV current path but leaves the current sensor in the same place, measuring nothing.

Some lines change colour irrationally in this diagram, confusing the meaning. For instance, the correct connection of B- to EVMS pin 8 changes from the intended black (HV NEGATIVE) to blue (which is supposed to be BMS SIGNAL WIRE).
It would probably make sense to check each wire to see if it does what it is intended to do and is shown appropriately. Obviously HV+ and LV+ wires would never be connected together, so when you see that it tells you that either the connection is wrong of the colour coding is wrong.
Yes I did notice this and I was a little premature with posting this wiring diagram until I really grasped the concept. I will be uploading a new wiring diagram to the best of my ability and will be sure to consider the wiring connection to each part and go through some logic steps.

On the main contactor, one of the pins has a LV output is this correct? I found a generic wiring diagram that I would like to use as a small guide that shows the lv system coming from a contactor. What is the reason behind the positive and negative contactor as well?
 

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Discussion Starter · #6 ·
Had some much needed time to revise the wiring diagram. This is the more crucial of the 2 diagrams as I am still working on the accessories (lights, blinkers, stop switches, etc.)

What is everyone's thoughts on the matter?

A few concerns I had and couldn't find the answer to:
- The charge sense (4) and the charge enable(11), can these be activated by the magnetic reed switch I have for the charging latch hinge? Basically when the latch opens, both of these would see a signal and be able to charge correctly or would I have to have a relay for the charge enable? The ZEVA BMS Manual states:
Connect to the +12 terminal of a relay which can enable your charger (usually turning the AC supply on, or charge enable input pins supported by some chargers). The other side of the relay should be connected to ground/chassis.
Would I need a 110V/220V relay that sends out a 12V signal for this and if so, where can I find one?

- Would the key switch and kill switch configuration work? In this set up, this is keeping the precharge resistor on the whole time, would I have to have a different relay, maybe a 2 way relay some how to turn the precharge off or? My thought in this was to have the estop button shut everything off, turn a key to enable the head lights, maybe tail lights along with the precharge resistor and then the kill switch would turn on the main contactor giving full power to the motor and the rest of the accessories, blinkers, horn. Would this work?

-The ZEVA BMS has temp sensors with 2 connectors, where would the second connector go? Does it simply go to ground? The manual doesn't have any information on this. Could I put more sensors on even the the main control board for the BMS only has 2 MPO (Multi purpose outputs)? I wouldn't mind having another temp sensor in the controller and motor area to monitor those temps. Applying those temp sensors to the respected components, can I use simple tape to adhere to the surfaces I am wanting? Will the heat make the glue of the tape come off?

-What size of fuses will I need for my accessories? Anything major should be over 10-15A?
 

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Had some much needed time to revise the wiring diagram. This is the more crucial of the 2 diagrams as I am still working on the accessories (lights, blinkers, stop switches, etc.)

What is everyone's thoughts on the matter?
I don't think you understand the purpose or function of a current sensor at all. I originally noted this:
I don't understand the wiring of the current sensor. It is intended to measure the current out of or into the battery, and communicate that information via CAN to the EVMS; the CAN wiring is shown (also connecting to the BMS slaves), but the HV current connections are not in the HV current path. The example on page 6 of the EVMS manual shows the current sensor properly in series between the battery and everything else; the modified version moves the HV current path but leaves the current sensor in the same place, measuring nothing.
... and in the new version the same problem is there, just in a big bold red line. There is a high voltage wire running as a pointless loop in a box around the EVMS. Since it is just a loop, no current will flow through the current sensor. All of the of current flowing directly to the DC-to-DC and through the main contactor to the motor controller bypasses the current sensor, and current from the charger will also flow directly to the battery; the current sensor might as well be discarded, and much of the EVMS functionality won't work.

Imagine current trying to flow through the wires is like a car traffic moving on streets. To go from the HV B+ to anything else, the easiest route does not go through the current sensor, so none will.
 

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- The charge sense (4) and the charge enable(11), can these be activated by the magnetic reed switch I have for the charging latch hinge? Basically when the latch opens, both of these would see a signal and be able to charge correctly or would I have to have a relay for the charge enable? The ZEVA BMS Manual states:
Connect to the +12 terminal of a relay which can enable your charger (usually turning the AC supply on, or charge enable input pins supported by some chargers). The other side of the relay should be connected to ground/chassis.
Would I need a 110V/220V relay that sends out a 12V signal for this and if so, where can I find one?
Charge sense and charge enable are not the same thing, and you have wired them to each other.

Charge sense is an input from a switch; yes, you could connect that to the charging latch switch, but I think they probably expect you to not turn on (enable) charging until after the AC cord is fully plugged in.

The quoted section is about charge enable. Perhaps it isn't clear to you, but it is telling you to use a relay, which is operated by 12 volts and controls the AC power. The EVMS is supplying the +12 V signal (out the charge enable terminal) to operate this relay, which you must supply.
 

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The EVMS manual says that it can have an internal precharger. If yours has that, it would not make sense to use another precharge resistor as well. You have used multiple key switch contacts and two relays, and it's not clear why... the key switch is an input to the EVMS; you shouldn't need to add anything else as far as the high voltage is concerned.

The EVMS internal precharger connects HV+ (terminal 7) to a wire running to the controller side of the main contactor ("Main Ctr Cathode", terminal 6) through a resistor. You have the wire in your diagram; why add another whole precharging system?

The EVMS is designed to minimize what you need to provide, and you don't seem to be using any of it, other than the BMS functionality. Maybe you just don't understand any of it?
 

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The CAN system allows multiple devices to be connected in a chain; the current sensor and the BMS slaves in this example. The EVMS diagram shows the terminator which is required at the end of a CAN chain... but you're missing the terminator. Without the terminator, CAN communication won't work properly.
 

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Discussion Starter · #11 ·
I don't think you understand the purpose or function of a current sensor at all. I originally noted this:

... and in the new version the same problem is there, just in a big bold red line. There is a high voltage wire running as a pointless loop in a box around the EVMS. Since it is just a loop, no current will flow through the current sensor. All of the of current flowing directly to the DC-to-DC and through the main contactor to the motor controller bypasses the current sensor, and current from the charger will also flow directly to the battery; the current sensor might as well be discarded, and much of the EVMS functionality won't work.

Imagine current trying to flow through the wires is like a car traffic moving on streets. To go from the HV B+ to anything else, the easiest route does not go through the current sensor, so none will.
Thank you for noticing this and I believe I have fixed this issue with simply removing the connection to allow it to flow directly to the contactor.

I will up load the wiring diagram as soon as I finish reviewing your comments. Again, I thank you for helping with this.
 

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Discussion Starter · #12 ·
Charge sense and charge enable are not the same thing, and you have wired them to each other.

Charge sense is an input from a switch; yes, you could connect that to the charging latch switch, but I think they probably expect you to not turn on (enable) charging until after the AC cord is fully plugged in.

The quoted section is about charge enable. Perhaps it isn't clear to you, but it is telling you to use a relay, which is operated by 12 volts and controls the AC power. The EVMS is supplying the +12 V signal (out the charge enable terminal) to operate this relay, which you must supply.
Is there a specific relay I am needing? Would I need a relay that would handle the 120V/240V when the signal is sent out from the EVMS? Again, I will upload a new wiring diagram when I have finished reviewing your comments.
 

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Discussion Starter · #13 ·
The EVMS manual says that it can have an internal precharger. If yours has that, it would not make sense to use another precharge resistor as well. You have used multiple key switch contacts and two relays, and it's not clear why... the key switch is an input to the EVMS; you shouldn't need to add anything else as far as the high voltage is concerned.

The EVMS internal precharger connects HV+ (terminal 7) to a wire running to the controller side of the main contactor ("Main Ctr Cathode", terminal 6) through a resistor. You have the wire in your diagram; why add another whole precharging system?

The EVMS is designed to minimize what you need to provide, and you don't seem to be using any of it, other than the BMS functionality. Maybe you just don't understand any of it?
I am understanding it, but this is new and wasn't aware of the terminology and definitions of these items. I have a more basic understanding and hence my reasoning for uploading my stuff here for help and criticism.

My reasoning for the multiple switches, as I mentioned, was to have the separation and allow the precharge to be turned on first along with the headlights and have an emergency kill switch on the handle bar like any other bike.
 

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Discussion Starter · #14 ·
I have uploaded the changes that were recommended. I do believe my key switch and kill switch are wrong and would like some help for this configuration:

I am wanting to turn on the EVMS which has the internal precharge resistor needed, but not turn on the main contactor. I would like the kill switch on the handle bar to be able to turn the HV main contactor on in case I need to kill the motor power.

As far as the temp sensors, what is the second lead for the temp sensors? Does it loop back into itself with the connector from ZEVA or?
 

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My reasoning for the multiple switches, as I mentioned, was to have the separation and allow the precharge to be turned on first along with the headlights and have an emergency kill switch on the handle bar like any other bike.
Sure, but the EVMS will presumably take care of ensuring that the precharge has had a chance to work before enabling the main contactor, and you can still add a kill switch more simply.
 

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Discussion Starter · #17 ·
Sure, but the EVMS will presumably take care of ensuring that the precharge has had a chance to work before enabling the main contactor, and you can still add a kill switch more simply.
I saw the other thread for the relay and will look into that relay a bit more. Would it have to be 2 separate relays, one for the 120V plug and one for the 240V plug or have one with a limit of the higher 240V plug? What suggestion would you have for the kill switch setup I am after? Again, I really appreciate the feedback.
 

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I am wanting to turn on the EVMS which has the internal precharge resistor needed, but not turn on the main contactor. I would like the kill switch on the handle bar to be able to turn the HV main contactor on in case I need to kill the motor power.
Why? Why not let the EVMS do handle the startup sequence, as it is designed to do. Connect your keyswitch to the keyswitch input of the EVMS (terminal #3), and let the EVMS first precharge then turn on the main contactor (terminal #9). You can still have a separate kill switch between the EVMS Main Contactor output (#9) and the contactor.
 

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Discussion Starter · #19 ·
Why? Why not let the EVMS do handle the startup sequence, as it is designed to do. Connect your keyswitch to the keyswitch input of the EVMS (terminal #3), and let the EVMS first precharge then turn on the main contactor (terminal #9). You can still have a separate kill switch between the EVMS Main Contactor output (#9) and the contactor.
I honestly wasn't aware the EVMS did all of that internally. It makes it so much easier doing it that way. Make it stupid simple they say. I really appreciate it brian_. I will upload a new wiring diagram later this evening for those changes.
 

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Thank you for noticing this and I believe I have fixed this issue with simply removing the connection to allow it to flow directly to the contactor.
That's closer, and now current through the main contactor to the motor controller goes through the current sensor, but current from the battery charger and to the DC-to-DC converter both still flow directly without going through the current sensor. As a result, the EVMS will know how much current is used from the battery by the motor, but not how much is used by the DC-to-DC or added by the charger.

The EVMS tries to determine how much charge is in the battery by monitoring how much goes in and out, so this way it will have no way to know what is left in the battery; it is as if you were trying to keep track of how many people were in a building by counting how many go in and out the front door, but left a back door open so an unknown number go in and out.
 
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