how to program a sevcon gen4

Hello everyone, thank you so much for the suggestions and feedback! Sorry about the few day break- this week has been kind of crazy with midterms and other assignments. Updates since the last post are as follows:
- I reflashed the gen4 with new firmware SN0058.28 (turns out the one it was running when we got it was not for PMAC)
- a new DCF file has been loaded and configured with the data for our setup on the new firmware (battery voltage, contactor, I/O, etc.)

Unfortunately I have not been able to try out the new suggestions for getting the encoder to line up because I now have a precharge fault on the controller that I cannot get rid of. I'm running a nominal 51.1V pack with the cutoffs set at the appropriate values for Lithium cells. The parameters are the same as they were in my previous DCF but the capacitors are only charging up to about 45V max which isn't the 85% needed for the contactor to close. Does anyone have any insight on to what could be causing this issue? I feel that I can't continue with motor testing until I get this bug figured out :/
The positive battery terminal is connected to pin 1 on the gen4 through a keyswitch and a fuse (unchanged since the beginning) and the battery is charged to ~56V so there should be no issues there. I have gone through the entire "tree" section in DVT and changed every value relating to voltages and cutoffs I could find as well.
 
I recall that the precharge system is sometimes finicky--did you check the pre-charge settings window? If the relay is not closing then the conditions for closure aren't being met, or the relay may not be operable by the Sevcon--I think it doesn't like PWM controlled relay economizers, like Gigavac sometimes has.

As a workaround, I think you might be able to disable the precharge and do it yourself.

Another super kludgey approach we used to do if this can't be disabled and you're in a hurry, you can turn on the key switch, let it precharge, wait till the precharge circuit has disengaged (the DC voltage will start dropping slowly), and at that time turn on your relay manually. If you don't wait too long and the timing is correct, the system will startup normally without error.

CAUTION: If you close the relay too early it will connect the battery to the precharge circuit and possibly damage it, that's the only way I have ever damaged a Sevcon, so I take no responsibility here.

There is a Sevcon troubleshooting thread somethere around here you can dig around.
 
That is a good point, can you please send us contactor setting window screen and what type of relay/contactor do you use?
 
everythingisawave said:
I recall that the precharge system is sometimes finicky--did you check the pre-charge settings window? If the relay is not closing then the conditions for closure aren't being met, or the relay may not be operable by the Sevcon--I think it doesn't like PWM controlled relay economizers, like Gigavac sometimes has.

As a workaround, I think you might be able to disable the precharge and do it yourself.

Another super kludgey approach we used to do if this can't be disabled and you're in a hurry, you can turn on the key switch, let it precharge, wait till the precharge circuit has disengaged (the DC voltage will start dropping slowly), and at that time turn on your relay manually. If you don't wait too long and the timing is correct, the system will startup normally without error.

CAUTION: If you close the relay too early it will connect the battery to the precharge circuit and possibly damage it, that's the only way I have ever damaged a Sevcon, so I take no responsibility here.

There is a Sevcon troubleshooting thread somethere around here you can dig around.

Also: also check that you aren't drawing any other power from the bus during precharge.
 
The contactor I am using is a 12-24V contactor (Kilovac EV200 I believe). It had a built-in economizer which was causing issues back when I first installed it a few weeks ago. So I took it apart and removed the circuit board so now the wires just go straight to the coil. My pull-in voltage is set to 16V with 12V for holding. The precharge level is 85%. I tried lowering the precharge to 75% and 70% but still no luck last night. I've noticed that every time I power on the controller the info window shows 3 errors:
1. precharge fail (the one I'm stuck with now)
2. power supply critical (not sure about this one since the battery is charged and I've changed the voltage cutbacks)
3. preop (the unit is just in preoperational mode)
My contactor is using contactor out #1, so it's just connected to pins 3 and 4 on the gen4.
 
Hmm.. you can also try to use small automotive 12V relay connected to Sevcon contactor output and so your Kilovac contactor will be switched by it on another 12V power supply. This will show you if there is problem with the current draw of your EV200. But more probably there is still some bug in the contactor settings.
 
I can try the smaller relay as a secondary switch as we have some in the lab, but would the contactor be what's causing the precharge fail? I feel like that would be something else, or am I wrong?
 
evc_motorcycle said:
The contactor I am using is a 12-24V contactor (Kilovac EV200 I believe). It had a built-in economizer which was causing issues back when I first installed it a few weeks ago. So I took it apart and removed the circuit board so now the wires just go straight to the coil. My pull-in voltage is set to 16V with 12V for holding. The precharge level is 85%. I tried lowering the precharge to 75% and 70% but still no luck last night. I've noticed that every time I power on the controller the info window shows 3 errors:
1. precharge fail (the one I'm stuck with now)
2. power supply critical (not sure about this one since the battery is charged and I've changed the voltage cutbacks)
3. preop (the unit is just in preoperational mode)
My contactor is using contactor out #1, so it's just connected to pins 3 and 4 on the gen4.

Can't remember if the contactor will energize in pre-op? But yeah as @Padja said I would try swapping out the contactor to see, and also use a voltmeter to check if it is even making an effort to close the contactor. Sometimes the inrush of the larger contactors is quite high. If you're using a lab power supply you should double check that the current limit is enough too (silly mistake I've made before).
 
in pre op the contactor will not engage.

try increasing the precharge time.

power supply critical error usually means the input it gets from the ignition is dicky. i have seen this with "scratchy" ignition switches as they are ment for 12V not 72V and the ignition contacts gets destroyed by pitting of the contacts.
try using a different switch or use a relay.
it uses that line to precharge so it does carry a bit of current during precharge and if the power is intermittent or the current flow changes a lot like with a dicky connection it can error out.
 
Thank you all for the suggestions. I hadn't considered a worn-out keyswitch. I will definitely try swapping out both that and the contactor next time I'm in the lab. If the keyswitch is in fact the issue then I will put a relay in the loop to take some of the load off the keywitch. When I measure the voltage from one side of the keyswitch to B- I get the full 56V, but when I measure from B- to B+ (with the contactor open), it is usually around 36-40V because the precharge isn't working correctly. I tried using a power supply initially, but had too many issues with tripping the overcurrent protection, so I switched to an extra kart pack we had in the lab. With regards to increasing the charge time, I don't believe I know where that parameter is located. Is that the "pull-in time" in the contactor branch?
 
Here you can see all contactor settings in older DVT 1.10 (licenced), as I mentioned before DVT software evolved during times and newer versions have more or different setting possibilities. But you could alway be able to set all parameters thru the "console" if you know their ID.

Also I must say that I have never worked with the oldest DVT (the one which did not need a licence) and so it is possible that some errors can be caused due to this outdated DVT.
 

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I am using DVT 1.0 (it is the only version we were able to get a copy of) and several of the GUI screens look different, such as the contactor one. I haven't used the command line for editing parameters, but I'm assuming all I need is the object dictionary and I just look up the address and write a new value to it? Is it right that the old version of DVT would still support writing to those addresses, even though they don't show up in the helper window?
 
Hi,
someone have the "CANopen utilities add-in" for Excel??
I try to generate a Object Database from the Master Object Dictionary.xls, but I got a error message, the add-in is not installed... :roll:
 
Hi everyone, I am super excited to say that I have the 1302 spinning up successfully with the Sevcon Gen4!!! Turns out that there was a single parameter (minimum capacitor precharge voltage) that does not show up in the helper window in DVT 1.0. Once I fixed this value (and used the motor phase order procedure) the motor spun! I've also added in an automotive relay on the keyswitch to avoid wear over time. The next few weeks will be tweaking and tuning and working on the actual installation process as the motor and all wiring is currently on a table. Thanks so much to everyone who gave input these past few weeks. I could not have progressed this far without your advice. I'm looking forward to posting more updates in other parts of the electric motorcycle forum! :D
 
Called it. Good job finding it.
 
evc_motorcycle said:
Hi everyone, I am super excited to say that I have the 1302 spinning up successfully with the Sevcon Gen4!!! Turns out that there was a single parameter (minimum capacitor precharge voltage) that does not show up in the helper window in DVT 1.0. Once I fixed this value (and used the motor phase order procedure) the motor spun! I've also added in an automotive relay on the keyswitch to avoid wear over time. The next few weeks will be tweaking and tuning and working on the actual installation process as the motor and all wiring is currently on a table. Thanks so much to everyone who gave input these past few weeks. I could not have progressed this far without your advice. I'm looking forward to posting more updates in other parts of the electric motorcycle forum! :D

How did you do with the encoder calibration?
 
I used the procedure outlined in one of the Sevcon manuals to determine the phase order of the motor we're using and which wire was sine and which was cosine. Once it was hooked up I followed the directions in another post on this forum and ran the encoder commision script. After graphing my voltage vectors (finally non-zero!) I got what is pictured below, and figured that since the line is close to the y-axis then the current offset was okay.
 

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evc_motorcycle said:
I used the procedure outlined in one of the Sevcon manuals to determine the phase order of the motor we're using and which wire was sine and which was cosine. Once it was hooked up I followed the directions in another post on this forum and ran the encoder commision script. After graphing my voltage vectors (finally non-zero!) I got what is pictured below, and figured that since the line is close to the y-axis then the current offset was okay.

That's how it is usually done but I'm curious about why it didn't work the first time, as we had provided suggestions about that and wondered what changed.
 
we really need to make a single (Read only) topic strictly on how to operate and commission a motor on a sevcon.
there is plenty of experience here but its quite spread out over the forum.

prehaps add some google drive links to a collection of DCF's and other files that might be of use. no need to learn to commision a motor and dick around with DCF's for days when someone else already did it on that motor.

if we can gather a bunch of links to existing posts i (or someone else) can mash them all together into a single topic/post for easy reference.
 
flippy said:
we really need to make a single (Read only) topic strictly on how to operate and commission a motor on a sevcon.
there is plenty of experience here but its quite spread out over the forum.

prehaps add some google drive links to a collection of DCF's and other files that might be of use. no need to learn to commision a motor and dick around with DCF's for days when someone else already did it on that motor.

if we can gather a bunch of links to existing posts i (or someone else) can mash them all together into a single topic/post for easy reference.

Good idea, a wiki would be great but would take more work.
 
flippy said:
we really need to make a single (Read only) topic strictly on how to operate and commission a motor on a sevcon.
there is plenty of experience here but its quite spread out over the forum.

prehaps add some google drive links to a collection of DCF's and other files that might be of use. no need to learn to commision a motor and dick around with DCF's for days when someone else already did it on that motor.

if we can gather a bunch of links to existing posts i (or someone else) can mash them all together into a single topic/post for easy reference.

:bigthumb:
 
evc_motorcycle said:
I used the procedure outlined in one of the Sevcon manuals to determine the phase order of the motor we're using and which wire was sine and which was cosine. Once it was hooked up I followed the directions in another post on this forum and ran the encoder commision script. After graphing my voltage vectors (finally non-zero!) I got what is pictured below, and figured that since the line is close to the y-axis then the current offset was okay.

nice, btw. what is the Encoder offset value for your ME1302?
 
Hi everythingisawave, I believe that the only things that changed between my weird (kind-of) circular graph and the one I recently posted were the firmware on my controller and the order of my sin-cos wires. I had determined the correct color association, but then plugged them into pins 35/21 in the wrong order :roll: . There was also a bad connection between the +5V supply and the ME1302 encoder, so that wire had to be replaced.
After those few things, the instructions here: https://endless-sphere.com/forums/viewtopic.php?t=88647 were what I used. Our dynamometer is currently out-of-commission, so I used the method with setting 0 torque and spinning the motor with a power drill.
 
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