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Got my motor turning today Wahoo

Posted: Mon, 12 Jan 2009, 00:00
by a4x4kiwi
For any Danfoss experts...

I tried changing the way I do reverse. instead of one profile and selecting reverse. (This gives a top speed of 80+ kph in reverse) I wanted to change profiles to go 'anticlockwise'.

Now. If I stay in one profile and change from 132Hz clockwise (which works fine) to 132Hz Anticlockwise the motor gets over torque errors at about 700RM and vibrates and hunts madly.

This might be one for the Danfoss tech.

Got my motor turning today Wahoo

Posted: Mon, 12 Jan 2009, 01:19
by acmotor
Not certain how to read your timeline there and being no expert on Danfoss I can only make suggestions. Please ignore them if you have already covered the points. Hopefully someone with inside knowledge will step in.

Most vehicles can do 80kmph in reverse so that should not be a concern.
You are likely to require full torque in reverse so depending on the setup, you may not wish there to be any limits.

How different is your setup from my speed mode ?

Beware the automatic interaction between parameter changes.
I have not found a description of these interactions other than that they occur as there is some obvious intelligence between par 100,200 and current / torque settings / feedback.

Guidelines do note that the parameters should be changed in a particular order and that some changes will change other related parameters and not reverse them if the original parameter is changed back. It all makes sense so you can't select the impossible.

Some parameters such as par 400 (brake function / overvoltage control) will change all 4 setups despite you being in the edit of only one setup. i.e. not all parameters can be changed by setup (1-4) change.

When in doubt, I go back and check all and try to keep one setup as my standard (known working) one.

Do consider the MCT10 software and RS485 connection with a PC as it has made setup and logging a whole lot easier / clearer for me.
I use an ADAM USB to RS485 converter to connect to the standard Danfoss RS485 serial bus, althought there are many other options for coms depending on your unit.(i.e. profibus etc).

Got my motor turning today Wahoo

Posted: Tue, 13 Jan 2009, 04:24
by a4x4kiwi
Thanks as always Tuarn.
I spoke to Danfoss today. No response on the problem yet.

As an aside, the mysterious earth and phase loss problems have gone away. touch wood.

I am running open loop and have essentially copied your configuration, and added the multi setup.

BTW, it works fine forward and reverse if I choose a single setup using Reversing.

I have the MCT10 software and my RS485 adapter arrived conveniently by post today. You are correct, much easier.

FYI here is my current and problematic configuration. Profile 1 is forward, 2 is reverse.

OK on the 80kph in reverse.
BTW, I see you are back to open loop control. what made you change?

I was hoping there was an over range error that could be tripped if the low side of the pot got disconnected for some reason. (only available on feedback) Have you mitigated this risk at all?

I was searching for VLT5000 info using Google and came across the following interesting point from ... hp?t=11281. I haven't tried it yet.

...There is several configurations to set for the starting torque. On Danfoss VFD there is a configuration, number 110, "motor magnetization at 0HZ", which is set at 100% as standard. This is a very important configuration to set in order to achieve highest possible starting torque. When i increased this setting to 200% all my starting problems and trips with nasty alarms disappeared...

Got my motor turning today Wahoo

Posted: Tue, 13 Jan 2009, 08:44
by acmotor
Re speed open loop. I blame you !!! I was inspired by your gear tooth inductive pickup and decided to remove my 4096 pulse encoder and go for an 8 tooth inductive PU, but haven't been happy with its operation (read non operation) so I've gone back to speed open loop and it works fine. Truth is, if I can get acceptable operation that way I will stay with it. Danfoss and others insist their sensorless control is good !

Torque open loop is less effective on start torque than torque closed loop though.

I found par 110 increases also increased cogging at low RPM under load, although this is not conclusive as there are other interactions going on there.

I would like to experiment with the user selectable v/f profile par 422-432 next.

Re pot low side error.
I have a micro-switch fitted to accel pedal as well to detect zero position. I do use it in series with ign 'start' momentary position to supply pulse start only if foot off accelerator. It could be used to short demand to VFD i.e. wiper to 0V if required. Where do you stop ?
If analogue inputs are 10kohm then when fed by 5k pot then O/C on the wiper results in zero demand. O/C on low side gives 67% demand. Not good but at least not 100%.

I'll look at your MCT10 file.

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 06:41
by a4x4kiwi
The speed sensor is now functional. If anyone would like to buy the old one, it will be suitable for a DC conversions to sense 2 pulses per revolution for the tacho. $30 and its yours. :)

Reverse using '132Hz anticlockwise' still messes up. In closed loop the motor spins to max RPM after being liner for the first few hundred RPM.

The only change in the program is from '132Hz clockwise' to '132Hz anticlockwise'

I am working with Danfoss support to try and resolve it but I fear it is a firmware problem or a fault in the drive.

My fall-back is to run in reversing mode using a single profile as Tuarn suggests.

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 06:47
by a4x4kiwi
I will have to take the blame for that one then :)

One annoying thing with open loop is that when 'running' while stationary, the displays a few RPM, not zero RPM. Does yours do that? I run the tacho and the speedo off this reading so I would like it to be correct if possible.

Thanks for the tip on the micro switch on the throttle pot. Great idea

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 06:52
by a4x4kiwi
Answering my own post must be a sign of insanity.
OK I can run the speedo off the feedback rather than calculated RPM so open loop would be OK.

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 08:13
by acmotor
Re non zero speed indication in open loop...

par 123 minimum frequency for activating function at stop, may need to increase this maybe 0.2% and check function at stop is coast.

par 309 / 310 scaling of reference (accel pot), min scaling may need to be increased if pot does not go to zero volts. You can display this voltage by scrolling on LCP (input terminal 53)

So many options !

I have never reversed a Danfoss by par 200 ??? Only ever by LCP or digital or RS485 input.
Do you need to change par 203 /204 / 205 as well to make sense ?

If you want 2 setups to switch between, use an otherwise unused digital input that can be set to 'reverse' for one of the setups (and NOP for the other) and leave all other pars the same except say the frequency limit.

Feel free to ignore me if you are on top of all this already !
I'll find a rock Image

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 08:27
by a4x4kiwi
good idea for reversing.

There is more than one way to skin a cat with this controller.

So many options.

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 20:33
by Johny
Mal, can I ask which sensor you ended up using - part number? I gather the teeth are unchanged and are still the same as that shown in your blog.

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 21:55
by a4x4kiwi
Hi Johny,

The teeth are unchanged (40). The sensor is the AE1-AP-1A.PNP, 1.5mm sense, cable    $49.50 from Automation Direct

Got my motor turning today Wahoo

Posted: Thu, 15 Jan 2009, 22:01
by a4x4kiwi
Thanks to Tuarn for all your help.

Here is my running config at the moment. I will connect the drive shaft on Sat. Wish me luck!

The related schematics are on my blog in case you need to make sense of the 3xx settings.

Setup 1 - Forward

ID          Name                     Value     
009          Display line 2          Feedback [unit]     
010          Display line 1.1     Dc link voltage     
011          Display line 1.2     Reference %
012          Display line 1.3     Output energy     
014          Local stop          Disable (0)          Prevents rapid deceleration.
102          Motor power          15.00     
103          Motor voltage          415     
105          Motor current          28.00     
106          Motor nom. speed     1450     
108          Stator resist          0.2641               From AMA
109          Stator react.          20.33               From AMA
113          Lo spd load comp     0     
114          Hi spd load comp     0     
115          Slip compensat.          0     
119          High start torq.     0.5     
123          Min.f. func.stop     0.1     
128          Mot.therm protec     Etr warning1     
200          Out freq rng/rot     132 hz bothirections     
205          Max. reference          132.000     
206          Ramp type          S2 (2)               Gives better low speed control.
207          Ramp up time 1          6.00               Economy
208          Ramp down time 1     3.00               Economy
209          Ramp up time 2          4.00               Power
210          Ramp down time 2     2.00               Power
221          Torq limit motor     348.5               drive Max.
222          Torq limit gener     66.6               10kW max regeneration
227          Warn. feedb. low     -4,500.000     
228          Warn. feedb high     4,500.000     
300          Digital input 16     Setup select LSB     
301          Digital input 17     No operation     
302          Digital input 18     Latched start     
303          Digital input 19     No operation     
305          Digital input 29     Ramp 2 (17)          Power / Economy switch
306          Digital input 32     No operation     
307          Digital input 33     Encoder feedback input A     
314          Ai [mA] 60 funct     No operation     
319          Ao 42 function          Fb min-max =0     
320          Ao 42 puls scale     66               Speedo Cal
321          Ao 45 function          Fb min-max =0     
322          Ao 45 puls scale     144               Tacho Cal (Check if should be 150 = 4500/60*2)
323          Relay 1-3 funct.     No operation     
325          Relay 1-3 off dl     0     
326          Relay 4-5 funct.     No operation     
329          Encoder pulses          40     Set for speed pickup
345          Enc loss timeout     0.2     
409          Trip delay torq.     60               Maximum
410          Inv.fault delay          35               Maximum
411          Switch frequency     14.0               Maximum          
415          Max. feedback          4,500.000          This value should be 10% higher than par. 205
416          Ref/feedb. unit          Rpm (3)     
422          U0 voltage (0hz)     7.3     
445          Flying start          Enable (1)     
446          Switch pattern          60° avm (0)     
457          Mains imbalance          Warning (1)     

Setup 2 - Reverse (Changes From Setup 1)

205         Max. reference         50.000          
303         Digital input 19       Reversing (1)

Got my motor turning today Wahoo

Posted: Sat, 17 Jan 2009, 02:05
by a4x4kiwi
New topic started called AC Tuning