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KiddZimaHater
02-17-2010, 08:57 PM
My VFD has a parameter setting for "Motor Nominal Current - Allowed Range .2 to 2.0 * /2nA (must be equal to value on motor rating plate).
HUH ????
My motor plate has nothing labled about "Nominal Current".
230volt
5.8 Amp
60Hz
3 Phase
2Hp
Ser. F. 1.15
Rating 40c
What should I enter for this parameter?

Bguns
02-17-2010, 09:20 PM
Strange wording
I would just put in 5.8

If it won't take that, than 1.0

millwrong
02-17-2010, 09:27 PM
Are you sure your VFD is sized for your motor? Nominal current should be the nameplate rate. If it is rated for 6 Amp-then enter the highest nominal value. If the VFD is not rated for 6 amps-then you will have a problem...

KiddZimaHater
02-17-2010, 09:33 PM
Nope, the VFD is rated at 16.8 Amps, 240 volt.
So I guess I should enter the Amp rating- 5.8?

lakeside53
02-17-2010, 09:35 PM
Yes.. it's just the nameplate current. It's "nominal" because any motor can exceed this number... The VFD is smart enough to allow short term overloads based on this number.

millwrong
02-17-2010, 09:39 PM
Allowed Range .2 to 2.0 * /2nA (must be equal to value on motor rating plate).

Are you sure about the 0.2 to 2.0 value?:confused: The "must be equal to motor nameplate", is the right answer. Your values above are whats throwing a bit of caution into the mix. If the drive accepts your nameplate value 0f 5.8 Amps-then you're golden:cool: Nothing like commissioning to lose some hair over.;)

KiddZimaHater
02-17-2010, 09:58 PM
Yeah, the ".2-2.0" value is in the operator's handbook. The handbook is written for European settings, not U.S.A.
If the handbook were published in the U.S. it would be in 5 different languages, with 5 different conversion equivalents. Political Correctness.:rolleyes:

rdfeil
02-17-2010, 10:20 PM
Kidd,

Is there anywhere in the setup to enter 'motor full load' current? If there is then the above mentioned setting MIGHT be for the service factor (SF) on your nameplate. This is just a maybe... I really have no idea from your description. I would call ABB's support line, the number should be in the book or on-line if the book only lists European numbers, and ask them what it means. I have seldom had to call ABB but when I have they were very helpful and knowledgeable.

Edit: I found the link to the manual in your other post and the answer is...... I have no idea what they want :rolleyes: . I would call ABB in the morning and have them explain what they want. If you do call and get the answer PLEASE let us know what they said. I would really like the answer explained to me.

Robin

J Tiers
02-17-2010, 11:11 PM
Looking at the ACS320 manual, page 129, code 9906 motor nominal current

the setting of 0.2 to 2.0 is with reference to the drive current.

So you should be able to put in the motor current as per the nameplate. the drive will either accept it or not, depending on what the rating is. If the drive is suitable for your motor, as it seems it should be, it will take it.

gearedloco
02-18-2010, 01:39 AM
Yeah, the ".2-2.0" value is in the operator's handbook. The handbook is written for European settings, not U.S.A.
If the handbook were published in the U.S. it would be in 5 different languages, with 5 different conversion equivalents. Political Correctness.:rolleyes:

Nah - them's probably Euro-Amps. They's bigger than U.S.A. amps. Probably metric, too. Maybe you gotta multiply or divide by Pie or sumthin.:p

-bill (Who is waiting for Nurse Diesel to come with his injection):eek:

Paul Alciatore
02-18-2010, 02:18 AM
Some people should not be allowed to write instructions.

Call them. Ask. Let us know.

Jim Shaper
02-18-2010, 02:23 AM
Make and model of the vfd would help us a lot more than all the stuff you've posted about your motor.

Evan
02-18-2010, 03:29 AM
"Allowed Range .2 to 2.0 * /2nA (must be equal to value on motor rating plate).
"

The range .2 -2.0 is a multiplier factor to be applied to the nominal motor current which is designated as I2n amps. It isn't a slash, it is the capital letter I for Amps and refers to the actual 100% duty cycle Normal motor current. It's actually N as in Normal, not nominal. Set the multiplier to 1.0 and the I2n to the nameplate current.

Then set Inmax to 1.1 the I2n value

whitis
02-18-2010, 03:33 AM
Don't confuse your VFD input ratings (single phase, includes inrush) with the output ratings (three phase).



The range of this number is 0.2 to 2.0*I2N, not 0.2 to 2. So, you probably enter 5.8 for this number. I2N is the rated current of the drive which is about 7.5A if you have the 2HP model. Make the range you are allowed to enter 0.2 to 15.0.


On your other thread you said you had and ACS150 drive (not an ACS320).
http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/4347a4759b348013c12576a500313486/$File/EN_ACS150%20UM_rev%20B.pd
http://www05.abb.com/global/scot/scot239.nsf/veritydisplay/5bc040ca1b11dc7d852574630062ab16/$File/ACS150PHTC01UEN_REVC_WEB.pdf
http://www.abb.com/product/seitp322/dced894f9370b1be8525720a004cdaf8.aspx
Which you listed as 0.5 to 5HP. However, that isn't likely the case. Rather, there are different ACS150 models which have different ratings from 0.5 to 5HP max. You could have a 1HP model which is inadequate to drive your 2HP motor at full power. You need the full model number, such as "ACS150-01U-07A5-2". If the digits "07" in this model number are lower in your model number, your drive is probably too wimpy to drive a 2HP motor at full power. Look in the product flyer (second link) table on page 6 to see what your model number means.

Post the FULL model number, the three links above, and the motor data if you start any new threads though it would be more appropriate to continue in one of the existing threads rather than cluttering up the BBS with multiple threads.

Evan
02-18-2010, 03:49 AM
I2N is the rated current of the drive which is about 7.5A if you have the 2HP model.

I2n is the rated current of the motor, not the drive.

http://www.joliettech.com/abb_acs-800_ac_drive_specifications.htm

J Tiers
02-18-2010, 08:39 AM
I2n is the rated current of the motor, not the drive.


I don't think so

The MANUAL actually says this:


MOTOR NOM CURR 0.15*I2N…1.5*I2N 0.1 A 1.5*I2N 
Defines the nominal motor current.
• Must equal the value on the motor rating plate.
• Range allowed: (0.2…2.0) IN (where IN is drive current).

So some confusion is in order........

No doubt the real intent is the motor current is to be entered, and the 0.2 to 2.0 factor is intended to be the range of motor currents that the drive is capable of measuring and limiting, or some such thing. However, the manual is particularly BAD, and ABB should be hung up by their thumbs.

it would be NORMAL for the drive to have an upper AND A LOWER limit on acceptable controllable motor current, so the idea that the I2n is DRIVE current is surely correct.

The manual for an Invertek drive is short, to the point, and explains how to get the drive going easily, WITH an explanation of each and every parameter....... and the book is maybe 20 pages or so. The ABB manual is HORRIBLE.

malbenbut
02-18-2010, 09:06 AM
Set at the vfd to the factory default parameter for the max current. It will be ok.
MBB

Evan
02-18-2010, 09:25 AM
I see no confusion Jerry. The parameter is called I2n because you may overdrive by up to double if you wish ( 2 times N). You are setting the maximum current the drive will deliver in 100% duty cycle operation. Naturally that should be made equal to the motor spec.

airsmith282
02-18-2010, 09:36 AM
if the motor says it wants or uses 5.8 then that is the draw for running amps that it will use, all motors when first fired up all use more then the rated for the startup then settle to the in this case 5.8 amp. now if you over load the motor it will draw more and you usualy blow a fuse at this point. no big deal..

my mill has a 9 amp motor and it uses a 10 amp fuse so i can do what i want with in the 9 amp draw but when i start to demand more from it the fuse pops after about a min sometime less, so i have pretty much learned now after pop several fuses how much i can push the mill, and sence then never blew a fuse sence,, if you do pop a fuse allow the machine to cool down for a bit other wise youll pop a few more been there done that,.

so ya pop in the value 5.8 and see what happens,,the rating on yout vfd is its max it can handel.

draw amps is what something uses.. rated is what it can handle as a max draw before it fails..

Jim Shaper
02-18-2010, 09:42 AM
With supplemental cooling (sometimes without), you can safely exceed the nameplate rated current for short durations. What Evan has said is correct. The multiplier has to do with how the drive will handle overloading.

KiddZimaHater
02-18-2010, 06:44 PM
I called Tech Support. He told me to enter the Amperage rating on my motor plate (5.8 Amps).
It would be alot easier if they just wrote that in the manual. Enter motor Amps in parameter XXXX.
SHEESH:(

J Tiers
02-18-2010, 09:50 PM
I called Tech Support. He told me to enter the Amperage rating on my motor plate (5.8 Amps).
It would be alot easier if they just wrote that in the manual. Enter motor Amps in parameter XXXX.
SHEESH:(

Yep, they could just bag that bit about the limits, if you buy a correct drive for your motor, it won't be an issue.


their point seems to be that if your motor current is radically different from the max drive current, the drive may not be able to control it correctly. So for a 16A drive, they don't want you to connect a motor with a nominal current under 0.2 x 16A, or 3.2A, because the drive may not measure small enough currents with sufficient accuracy to properly control it.

Those various 'symbols" all mean something specific if you are fluent in "IEC-speak".....

But that is not so easy to be fluent in.... In the US there are various HP of contactors, for instance, and any given contactor has a specific rating. But in the IEC world, there are something like 56 different generally used current ratings that may apply TO THE SAME CONTACTOR. Each rating is for slightly different conditions, and each may result in a different current spec.

Likewise there are a lot of "symbols" like the "I2n", including ratings like AC3, AC14, AC22, etc, which are some of the above-mentioned current ratings, or "Un" and a host of other ones that mean voltages, etc, etc, etc. You need a book to decipher them, and because each has a precise meaning, the 'symbol" is ALWAYS used in preference to any explanation.

ABB could have explained it in a definitions area. For all I know somewhere in the hundreds of pages there may BE an explanation of the "symbols" used in that manual.

whitis
02-18-2010, 11:18 PM
I2n is the rated current of the motor, not the drive.

http://www.joliettech.com/abb_acs-800_ac_drive_specifications.htm

Well, not only did you post a link a page that deals with the wrong model drive, but even that supports my assertion rather than your contradiction of it:
"ACS 800 Specifications: Output Connection: Continuous Current 1.0*I2N (normal use)"
If you look at the actual product flyer for the correct series of drive, it says this:
"Technical specification ... Output connection ... Continuous loading capability ... Rated output current I2N"
I wrote:
"I2N is the rated current of the drive".

For short periods of time and low duty cycle, you are allowed to exceed that.

And no, I2N, does not need to match the motor specs, though they shouldn't differ too radically. On the 2HP model, you can probably connect a 0.5 or 1HP motor. And apparently, you can connect up to a 4HP motor though it will not be driven at full capacity. If you connect an 8HP motor, you might burn out the drive because even though the drive tries to limit the instantaneous output current to the lower of the drives instantaneous rating or the motors estimated instantaneous rating, it may not succeed with the lower inductance of a large motor and measuring range limits of the sensors. If you connect a 0.1HP motor, the drive may have some difficulty due to quantization error or noise due to internal scaling of measurements.
So, if you have a 2HP drive, you can probably use a 0.4HP to 4HP motor with it but motors over 2HP will be run at reduced power. This means you have the option of buying a better drive than your current motor requires or can use the same drive for different devices with different size motors.

Do not confuse I2N with the parameter 9906. The value you enter in 9906 is the value from the motor nameplate. The allowed range of parameter 9906 is either 0.2 to 2.0*I2N or 0.2*I2N to 2.0*I2N (yeah, poorly written); I2N is not the value entered in 9906.

KiddZimaHater: "It would be a lot easier if they just wrote that in the manual". They did, more or less. Page 40. "Enter the motor data from the motor nameplate ... (illustration of motor nameplate) ... motor nominal current (parameter 9906) ... Note: Set the motor data to exactly the same value as on the motor nameplate". Amps, abbreviated with an "A" suffix, are the unit current is measured in. It also asks for nominal voltage and nominal frequency.

"Nominal" may confuse some, since there are non-engineering uses of the word that have different meanings and lay dictionaries don't have much of a clue as to how the word is actually used in millions of technical documents. Nominal is usually the named/rated/ideal/normal/official/target/basis/specified value of some quantity, not the actual. It is the "named" or "in name only" value. Data sheets frequently read like this: Min: 1.8 Nominal: 2.0 Max: 2.2. I.E. 2.0+/-0.2 or 2.0+/-10%. The nominal value is usually the basis of the tolerance band, it isn't necessarily the center. If I ask you to make a part that is 2.000"+/-0.005", then 2.000" is the nominal value. If I ask you to make a part that is 2.000"+0.000/-0.010 (unilateral tolerance), then 2.000" is still the nominal value. I.E. the dimension is ideally as close to 2.000" as you can get without exceeding it. While a 1.998" and a 1.992" part both will pass inspection, the 1.998" part is usually a superior fit. If you are using a Chinese 7x12" lathe and import calipers, you may aim for 1.995 in the hopes that your misses will be within tolerance. If you are using a monarch 10EE and calibrated measuring instruments, you may aim for 1.999" because you can hit closer to the nominal value and still have almost all your misses under 2.000". If I have different grades of parts, the nominal dimensions on both may be 2.000" but the tolerance band is narrower on some. Things can get weirder with things like lumber and pipes. The nominal dimensions of a 2x4 are 2"x4", but the tolerance band of a finished (after planing, as normally delivered) 2x4 doesn't even include 2"x4". It is a 2x4 "in name only".

If they make three of the same model 5.8A motors and one tests at 5.7A, one at 5.8A, and one at 5.9A under full load due to manufacturing variations, the nameplate on all three still says 5.8A. It is the "named" value, not the actual value. Ignoring the rounding up fudge factor, of course.

If I ask you what the nominal spindle bore diameter of your lathe is, you might say 1.375" (1-3/8") if I ask what the actual diameter is, you might say 1.382".



FULL LOAD AMPS (FLA)
When the full-load torque and horsepower is reached, the corresponding amperage is known as the
full-load amperage (FLA). This value is determined by laboratory tests; the value is usually rounded
up slightly and recorded as the nameplate value. Rounding up allows for manufacturing variations that
can occur and some normal voltage variations that might increase the full-load amps of the motor.
The nameplate FLA is used to select the correct wire size, motor starter, and overload protection
devices necessary to serve and protect the motor.
Rated full load current is often abbreviated as ‘FLA” on the nameplate. Unbalanced phases, under-
voltage conditions, or both, cause current to deviate from nameplate amps.

http://www.pdhcenter.com/courses/e156/e156content.pdf

[/QUOTE]

EDIT: Page 113 gives the values for I2N and page 114 defines it as "I2N continuous rms current. 50% overload is allowed for one minute every ten minutes".
And no, it isn't called I2N because you can exceed it by a factor of 2. I1N is the input current to the drive.

KiddZimaHater
02-18-2010, 11:37 PM
Sorry I'm so Electrically Ignorant. Amps, Volts, Jiggawatts, "NOMINAL FREAKING CURRENT", Watts, N/12A*%@Ratings, Blah Blah Blah, Frequencies,American ratings, European settings........
I just want my damn lathe cutting metal again!!!!
I'm a machinist, not an electronics engineer for cripes sake!
(By the way....Thanks everybody for your help):o

J Tiers
02-19-2010, 08:41 AM
So buy a drive that does not need a consultant to set it up.

They exist.

You have to realize that european rules are set up in the context of a long history of regulation, regimentation, guilds, unions, and "experts". There are 'experts" for everything, people who are "supposed" to do that, and people who are not. You would be the latter.

"You" are NOT SUPPOSED to set that up, you are supposed to call in (and pay) an "approved, certified expert" to do it. And a different one to wire it.

And whenever you want to change something, you are supposed to get that "telephone sanitizer 1st class" back in to do it for you.

it's a different mindset, and has a lot to do with why we live here and not there.

The manual was written from that background, even though it is nominally intended to allow anyone to use the device.

lakeside53
02-19-2010, 11:32 AM
If you don't like the ABB manual, try one of the chinese import VFDs... Oh, then try to call some to ask what it all means:D

Evan
02-19-2010, 02:19 PM
Well, not only did you post a link a page that deals with the wrong model drive, but even that supports my assertion rather than your contradiction of it:
"ACS 800 Specifications: Output Connection: Continuous Current 1.0*I2N (normal use)"
If you look at the actual product flyer for the correct series of drive, it says this:
"Technical specification ... Output connection ... Continuous loading capability ... Rated output current I2N"
I wrote:
"I2N is the rated current of the drive".


Right. In other words, the manufacturer requires the operator to tell the drive what it is capable of handling on the output. One would think that the manufacturer already knows this parameter. Further, if the motor exceeds it the drive can detect it and either limit it or shut it off.

What the drive doesn't know is how much current the motor should be operated at. That is what the I2n parameter designates.

KiddZimaHater
02-19-2010, 08:38 PM
WOOOOO - HOOOOO !!!!!!
I just finished wiring up the VFD and new motor, and WOW! what a difference.
Now I know why everyone sings the praises of VFD-3 Phase setups.
It so quiet. Full power. Smooth start-up.
Time to play.:) So Long 110.

J Tiers
02-19-2010, 11:05 PM
Right. In other words, the manufacturer requires the operator to tell the drive what it is capable of handling on the output. One would think that the manufacturer already knows this parameter. Further, if the motor exceeds it the drive can detect it and either limit it or shut it off.

What the drive doesn't know is how much current the motor should be operated at. That is what the I2n parameter designates.

Sorry Evan, you just don't "get it" on this one. You have it BACKWARDS

The manufacturer requires the user to tell the drive what the MOTOR requires...... So the drive "knows" how to avoid really clobbering the motor.

And they say that for any particular drive (the book may cover more than one) you should not program it with a motor current that is LESS than 0.2 of or MORE than 2 times, THE DRIVE RATED CURRENT.

Evan
02-20-2010, 12:58 AM
The manufacturer requires the user to tell the drive what the MOTOR requires...... So the drive "knows" how to avoid really clobbering the motor.


That is what I just wrote. I have nothing backward.

"What the drive doesn't know is how much current the motor should be operated at. "

EVguru
02-20-2010, 04:15 AM
That is what I just wrote. I have nothing backward.

"What the drive doesn't know is how much current the motor should be operated at. "

Yes, but you also wrote.


One would think that the manufacturer already knows this parameter.

How would they know?

Evan
02-20-2010, 04:44 AM
Read my reply in the context of the quote to which I replied. That was a bit of mild sarcasm. The parameter to which I referred in that sentence is the drive's current handling capability.

Bguns
02-20-2010, 05:12 AM
And I had a correct answer in post #2 :)

Only 3 VFD installs under my belt now..
All different brands.. AC Tech, Teco, Leeson...

Have 2 more to do for an ancient mill project.. (feed and spindle)

J Tiers
02-20-2010, 11:15 AM
That is what I just wrote. I have nothing backward.

"What the drive doesn't know is how much current the motor should be operated at. "

You did here....... as proven by the link you showed.


I2n is the rated current of the motor, not the drive.

http://www.joliettech.com/abb_acs-80...ifications.htm

Just don't worry yourself about it... the IEC ratings codes are troublesome, and the OP has the correct results now.

The point of the I2n spec is just as we said, to show the normal rated output current OF THE DRIVE. The spec shows some other specs as well, and the COMPLETE spec probably shows "I" specs over temp, and at different "overload ratings".

That set of limits on the allowable motor current lets you see what size motors you can connect. In this case, ones that draw between 0.2 and 2.0 times the I2n spec OF THE DRIVE.

Evan
02-20-2010, 02:13 PM
The point of the I2n spec is just as we said, to show the normal rated output current OF THE DRIVE. The spec shows some other specs as well, and the COMPLETE spec probably shows "I" specs over temp, and at different "overload ratings".

That set of limits on the allowable motor current lets you see what size motors you can connect. In this case, ones that draw between 0.2 and 2.0 times the I2n spec OF THE DRIVE.

You are contradicting yourself Jerry. Why would you have to tell the drive what it can handle? It already knows that and if you hang too big a motor on it it will simply not drive it to maximum capacity. The I2n spec is how you tell the drive what THE MOTOR can handle so it doesn't over drive the motor. There is no need to be concerned about the drive. It has multiple protection circuits and programs to handle loads. Telling the drive what the nameplate rating of the motor is only makes sense if the parameter is used to identify how much output to use, not to tell the drive how much it can handle as a load.

The multiplier lets you adjust the nameplate rating up and down for different configurations and short term operating conditions of the MOTOR. A multiplier is used because it would not make sense to enter incorrect values of the nameplate current in order to drive it harder or softer.

Just to make sure you understand my previous statement I will annotate it with the non-scarcastic meaning.

Right.(wrong) In other words, the manufacturer requires the operator to tell the drive what it is capable of handling on the output.(I don't think so) One would think that the manufacturer already knows this parameter.(of course it does) Further, if the motor exceeds it the drive can detect it and either limit it or shut it off.(statement of fact)

What the drive doesn't know is how much current the motor should be operated at.(reason for parameter) That is what the I2n parameter designates.

J Tiers
02-20-2010, 11:01 PM
Evan, You seem now to basically be quoting me, so I am going to assume you have now understood the matter, even though you appear to be trying to lecture me on what I just wrote before..

The reason for tying it to the DRIVE rating (I2n) is, as I and one or more others have said, because the DRIVE has limits on its resolution of current, as a percentage of ITS "I2n", or nominal output rated current.

For a vector drive, especially, the motor parameter measurement is only accurate between certain limits of nominal current. But the current transducers only accurately measure a certain range, and that applies to ANY type drive.

Evan
02-21-2010, 01:44 AM
The reason for tying it to the DRIVE rating (I2n) is, as I and one or more others have said, because the DRIVE has limits on its resolution of current, as a percentage of ITS "I2n", or nominal output rated current.


I am not quoting you Jerry and I haven't made the slightest change in my position.

What you just wrote doesn't even make sense. Exactly what is "limits on it's resolution of current" supposed to mean? I would expect that it can resolve to at least 8 bits and probably 16 in the ADC it uses to measure current. So what?

That particular entry is the only parameter that gives the drive the motor rating. The multiplier is used in several other parameters to tell the drive how much it can overdrive the motor for short periods of time. That makes it obvious that it has nothing to do with the internal limits of the drive nor is there any reason to expose those limits to the user, which it doesn't. The value of the motor current isn't tied to the drive rating by entering it in that parameter.

What is entered is a value relative to the motor only and it's normal operating current. When you use a multiplier other than 1.0 the resulting value is not a percentage of the drive rating, it's a percentage of the motor current rating. Since the user probably has no idea what the drive rating is it makes no sense at all to expect the user to tie an external parameter to a hidden internal parameter, and it doesn't. It also doesn't matter what the drive rating is since the drive will protect itself and if it can't handle the current it will shut down and declare an error.

What really makes it clear that the multiplier is a percentage of the MOTOR current and not the drive current is that the maximum overload capability of the drive is listed as 1.8 times the rated output for 2 seconds. Obviously the manufacturer would not allow the user to set a value that would exceed that so the maximum multiplier of 2.0 is a percentage of motor current, not drive capability.

Barrington
02-21-2010, 05:45 AM
Before this gets out of hand... ;)

Evan, I wonder if the root of this lies in a simple misreading of the table in the manual ?

For parameter 9906 - Motor Nominal Current, the 'I2N' in the final column is not the name of the parameter, it is simply the default value applied if the user does not enter a value for 9906.

As has been pointed out repeatedly and correctly, I2N is the nominal continuous rms output current capability of the drive, and thus is a reasonable value for the default in the absence of user input.

Just to be absolutely clear - I2N is not a user supplied parameter.


The parameter is called I2n because you may overdrive by up to double if you wish ( 2 times N).
'I2N' is nothing to do with 'double the current' or any such nonsense. (Being confused is one thing, but just making stuff up :mad: is quite another...! ).

The '2' part of the suffix is a seldom used convention and simply implies the 'second' or 'output' current of a system, a transformer, or whatever. Compare with 'I1N' which is also specified for this drive and is the nominal input current.

Cheers

.

Evan
02-21-2010, 09:08 AM
As has been pointed out repeatedly and correctly, I2N is the nominal continuous rms output current capability of the drive, and thus is a reasonable value for the default in the absence of user input.


Agreed that I2n is the output capability of the drive. However, the value the user enters is not referenced to I2n by the user and neither is the multiplier. The user tells the drive what the motor is rated at and how much it can take over that, if any, by specifying a percentage of MOTOR current using the multplier factor. The value entered is not "tied to the drive rating" as Jerry has stated.

Using the maximum current capability of the drive to run the motor in the absence of an input may or very well may not be a reasonable thing to do but that is a different question.

J Tiers
02-21-2010, 09:43 AM
because this may come up again, I'll stay in this crazy looking-glass world one more post........

The entered parameter "is tied to" or "relates to" the drive parameter because the drive has an upper limit on current (obviously) AND A LOWER LIMIT.

The LOWER LIMIT is probably a measurement resolution limit, and, in some cases, may be a "minimum pulse length" limit.

The latter means that the drive has a minimum length of pulse that it can produce, meaning that there is a minimum current that it has to source, below which the option is "off". if that is not sufficiently lower than the motor current, the drive is not suited to that motor, because it won't have the range of currents required to operate the motor acceptably.

So the "tie" between the motor current you can enter, and the drive I2n is simply another way (the IEC way) of presenting the range of motor powers the drive can handle acceptably. It is given in terms of a percentage range based on I2n.