Precharge Output
Precharge Output
Hi guys,
When I try to start the inverter in manual mode I get the MPHSMAX - DERATE error after running
set fweak 10
start 2
set fslipspnt 10
set ampnom 100
I think the issue is the precharge circuit. I looked at the relay output of pin 20. What should the output voltage be? I have changed the udcsw value to 75V and my DC bus is at 150V. I do not get any output on pin 20. Could someone help me please?
When I try to start the inverter in manual mode I get the MPHSMAX - DERATE error after running
set fweak 10
start 2
set fslipspnt 10
set ampnom 100
I think the issue is the precharge circuit. I looked at the relay output of pin 20. What should the output voltage be? I have changed the udcsw value to 75V and my DC bus is at 150V. I do not get any output on pin 20. Could someone help me please?
Re: Precharge Output
Remember the outputs are open collector. The relay must connect to +12V and output.
In other words the output is Z (off) and GND (on)
But i don't think you will get precharge in manual mode.
In other words the output is Z (off) and GND (on)
But i don't think you will get precharge in manual mode.
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Re: Precharge Output
TMPHSMAX means you have not connected the heat sink temp sensor or selected the wrong type or the heat sink is actually > 85°C 
Precharge is always enabled at startup and constantly stays on in manual mode. dcsw is not enabled in manual mode! Manual mode is targeted towards bench testing with a power supply or something like that.

Precharge is always enabled at startup and constantly stays on in manual mode. dcsw is not enabled in manual mode! Manual mode is targeted towards bench testing with a power supply or something like that.
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Re: Precharge Output
Hi guys,
Thanks for the response.
I connected the temp sense and it reads around 30°C.
I still get these errors when I run the inverter with fslipspnt 10 and ampnom 100. It is as the inverter work for a split of a second and then switch off. The error codes:
[501]: DERATE - TMPHSMAX
[52830]: WARN - THROTTLE1
My set of parameters:
{
"boost": 1700,
"fweak": 10,
"udcnom": 150,
"fslipmin": 1,
"fslipmax": 3,
"polepairs": 2,
"respolepairs": 1,
"encmode": 0,
"fmin": 1,
"fmax": 200,
"numimp": 60,
"dirchrpm": 100,
"dirmode": 1,
"syncofs": 0,
"snsm": 12,
"pwmfrq": 1,
"pwmpol": 0,
"deadtime": 63,
"ocurlim": 1000,
"minpulse": 1000,
"il1gain": 2,
"il2gain": 2,
"udcgain": 3,
"udcofs": 0,
"udclim": 540,
"snshs": 0,
"bmslimhigh": 50,
"bmslimlow": -1,
"udcmin": 450,
"udcmax": 520,
"iacmax": 5000,
"idcmax": 5000,
"idcmin": -5000,
"throtmax": 100,
"ifltrise": 10,
"ifltfall": 3,
"chargemode": 0,
"chargecur": 0,
"chargekp": 80,
"chargeflt": 8,
"chargemax": 90,
"potmin": 0,
"potmax": 4095,
"pot2min": 4095,
"pot2max": 4095,
"potmode": 0,
"throtramp": 100,
"throtramprpm": 20000,
"ampmin": 10,
"slipstart": 50,
"brknompedal": -50,
"brkpedalramp": 100,
"brknom": 30,
"brkmax": 30,
"brkrampstr": 10,
"brkout": -50,
"idlespeed": -100,
"idlethrotlim": 50,
"idlemode": 0,
"speedkp": 0.25,
"speedflt": 5,
"cruisemode": 0,
"udcsw": 330,
"udcswbuck": 540,
"tripmode": 0,
"pwmfunc": 0,
"pwmgain": 100,
"pwmofs": 0,
"canspeed": 0,
"canperiod": 0,
"fslipspnt": 10,
"ampnom": 100
}
Thanks for the help.
Thanks for the response.
I connected the temp sense and it reads around 30°C.
I still get these errors when I run the inverter with fslipspnt 10 and ampnom 100. It is as the inverter work for a split of a second and then switch off. The error codes:
[501]: DERATE - TMPHSMAX
[52830]: WARN - THROTTLE1
My set of parameters:
{
"boost": 1700,
"fweak": 10,
"udcnom": 150,
"fslipmin": 1,
"fslipmax": 3,
"polepairs": 2,
"respolepairs": 1,
"encmode": 0,
"fmin": 1,
"fmax": 200,
"numimp": 60,
"dirchrpm": 100,
"dirmode": 1,
"syncofs": 0,
"snsm": 12,
"pwmfrq": 1,
"pwmpol": 0,
"deadtime": 63,
"ocurlim": 1000,
"minpulse": 1000,
"il1gain": 2,
"il2gain": 2,
"udcgain": 3,
"udcofs": 0,
"udclim": 540,
"snshs": 0,
"bmslimhigh": 50,
"bmslimlow": -1,
"udcmin": 450,
"udcmax": 520,
"iacmax": 5000,
"idcmax": 5000,
"idcmin": -5000,
"throtmax": 100,
"ifltrise": 10,
"ifltfall": 3,
"chargemode": 0,
"chargecur": 0,
"chargekp": 80,
"chargeflt": 8,
"chargemax": 90,
"potmin": 0,
"potmax": 4095,
"pot2min": 4095,
"pot2max": 4095,
"potmode": 0,
"throtramp": 100,
"throtramprpm": 20000,
"ampmin": 10,
"slipstart": 50,
"brknompedal": -50,
"brkpedalramp": 100,
"brknom": 30,
"brkmax": 30,
"brkrampstr": 10,
"brkout": -50,
"idlespeed": -100,
"idlethrotlim": 50,
"idlemode": 0,
"speedkp": 0.25,
"speedflt": 5,
"cruisemode": 0,
"udcsw": 330,
"udcswbuck": 540,
"tripmode": 0,
"pwmfunc": 0,
"pwmgain": 100,
"pwmofs": 0,
"canspeed": 0,
"canperiod": 0,
"fslipspnt": 10,
"ampnom": 100
}
Thanks for the help.

Re: Precharge Output
Update:
I lowered the DC bus voltage to 50V from 150V and setting fslipspnt 10 and ampnom 20 started to turn my motor. Finally
When I increase ampnom to above 40 the inverter stop. I am trying to search for the cause but cannot get the it. My guess is some current limit? The ocurlim is set to 1000.
Any suggestions?
I lowered the DC bus voltage to 50V from 150V and setting fslipspnt 10 and ampnom 20 started to turn my motor. Finally

When I increase ampnom to above 40 the inverter stop. I am trying to search for the cause but cannot get the it. My guess is some current limit? The ocurlim is set to 1000.
Any suggestions?
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Re: Precharge Output
Can you post a plot of the il1 and il2 at 1000 samples and 1000 display limit? Is there any indication that the current is actually very high? Are the current sensors calibrated?
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Re: Precharge Output
You have to calibrate throttles first. Otherwise DC switch will not work. Since you have throttle parameter at 0 i am sure your pot value is sitting somewhere at 800pt? So first look in web interface how much the value is when pedal is released and then set min value some 50pt above this. Also i set max value at 4090pt.Jan wrote: ↑Tue Sep 17, 2019 12:08 pm Update:
I lowered the DC bus voltage to 50V from 150V and setting fslipspnt 10 and ampnom 20 started to turn my motor. Finally![]()
When I increase ampnom to above 40 the inverter stop. I am trying to search for the cause but cannot get the it. My guess is some current limit? The ocurlim is set to 1000.
Any suggestions?
Ampnom is 40% of amps available to the motor. I dont think you set it high enough. With low voltage you have to feed higher amps to the motor so rotor can overcome its internal resistance.
So i suggest you use 150Vdc like before.
Set boost higher like 5000
Set Fweak to like 60Hz
Set fpconst to 400Hz
set fmax at 60Hz
Set ampmin at 20, you can lower it later
Set ocurrlimit at 600A no need to go overboard
Measure current sensor gain per procedure here: https://openinverter.org/wiki/Schematic ... sor_boards
Hm... do you use positive current sensor gain? What kind of sensor board do you use? Old ones had gain negative
In web interface select start manual and then order ampmin for start somewhere at 70 and only then command slip in steps of 3hz up to some 9hz and then you can increase in steps of 10Hz. If you want to stop without regen you just set amp to 0 and then slip to 0.
And set deadtime to 83 before something bad happens to your IGBTs...
Re: Precharge Output
Hi guys,
2. See also attached the il1 and il2 recordings running the motor at with 50V DC bus.
3. Does not seem that current is high when I want to start at 150V.
1. I calibrated the sensors a while ago with motor running and the sensors connected to that motor. (attached) I only collected the RMS values though. Using gain of two was accurate enough for me.
2. See also attached the il1 and il2 recordings running the motor at with 50V DC bus.
3. Does not seem that current is high when I want to start at 150V.
I am using the new current sensor boards. I tried these setting without luck.arber333 wrote: ↑Tue Sep 17, 2019 7:19 pmYou have to calibrate throttles first. Otherwise DC switch will not work. Since you have throttle parameter at 0 i am sure your pot value is sitting somewhere at 800pt? So first look in web interface how much the value is when pedal is released and then set min value some 50pt above this. Also i set max value at 4090pt.Jan wrote: ↑Tue Sep 17, 2019 12:08 pm Update:
I lowered the DC bus voltage to 50V from 150V and setting fslipspnt 10 and ampnom 20 started to turn my motor. Finally![]()
When I increase ampnom to above 40 the inverter stop. I am trying to search for the cause but cannot get the it. My guess is some current limit? The ocurlim is set to 1000.
Any suggestions?
Ampnom is 40% of amps available to the motor. I dont think you set it high enough. With low voltage you have to feed higher amps to the motor so rotor can overcome its internal resistance.
So i suggest you use 150Vdc like before.
Set boost higher like 5000
Set Fweak to like 60Hz
Set fpconst to 400Hz
set fmax at 60Hz
Set ampmin at 20, you can lower it later
Set ocurrlimit at 600A no need to go overboard
Measure current sensor gain per procedure here: https://openinverter.org/wiki/Schematic ... sor_boards
Hm... do you use positive current sensor gain? What kind of sensor board do you use? Old ones had gain negative
In web interface select start manual and then order ampmin for start somewhere at 70 and only then command slip in steps of 3hz up to some 9hz and then you can increase in steps of 10Hz. If you want to stop without regen you just set amp to 0 and then slip to 0.
And set deadtime to 83 before something bad happens to your IGBTs...
Re: Precharge Output
HI Guys,
I changed the current sensors to one that I borrowed from a friend and now the motor is running at 150V.
Do you think there is something wrong with my sensor boards?
I changed the current sensors to one that I borrowed from a friend and now the motor is running at 150V.
Do you think there is something wrong with my sensor boards?
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Re: Precharge Output
Do you have a picture with them mounted? Maybe they caught some interference. Your plots don't look like high current though,
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