Hitachi VFD

Reset all parms to default according to this http://www.clrwtr.com/PDF/Hitachi/Hitachi-J300-Drive-Manual.pdf, note what must be changed and change ONLY that.

You realize (he says hopefully) that you have to PROGRAM the VFD as to where the command and control is going to come from right? And the program settings are DIFFERENT for where the Speed Command comes from and where the Control Command comes from right? So for example you can tell it "I want the Speed Command to be from the terminals" and you don't change the Control Command, then the On-Off-Fwd-Rev control will still be at the Keypad.

Hi Normbourne, I think that the problem is a programming issue if you look at parameter F9 it should be set to 02 or 03 depending where you want the speed control to operate from, if you want the speed control to operate from the key pad set F9 to 02, if it is from the terminals set it to 03.

Check out http://www.clrwtr.com/PDF/Hitachi/Hitachi-J300-Drive-Manual.pdf if is not the easiest manual to understand but it should get you up and running.

Cheers

Joe

If you can't change the software, perhaps the software lock selection function is active.

It is parameter F-25.

Keep in mind that the RS (reset) function is not activated. I remember they shipped the drive for a period with the Reset input terminal functioning as a normally closed contact and afterwards the changed the software and then the RS input terminal function was a normally open contact.

Hi Rudy,

As I did state, the manual is a minefield!

Not the most user freindly, but still workable.

You have had experience with these drives, you probally know more about the drive than I do, I have never worked with this drive, I only go on gut feeling and the experience that I have.

To be honest, I think that this drive is quite a few years old, the reason for this is the operator manual, it has been written by a boffin for a boffin, not written for a simple electrician like me.I agree with you check the parrameters, the answer is within the parrameters.

Best Regards

Joe

What the heck is a boffin?

a boffin is an expert ....

Hi Guys, It's all SORTED. It proved to be a parameters problem, after all, after a return to specs. and carefully going thro settings, I got it going...!!! Thanks guys one and all, for all your help. Best Regards, Norm

Hi Guys,

Further to recent success, I've query regarding deceleration times, is it best perhaps to keep the deceleration time as short as possible..? I have notice in the past with various drives, that when they are decelerating, the current tends to rise. The load incidentally is a vibrating plate. Does anyone have any thoughts on this. Norm.

When you decrease the motor speed to fast, ie, breaking the motor too heavy, there is a risk that the motor works as generator. The voltage over the buffer capacitor will increase and the drive will trip. You can use a breaking resistor for these purposes.

But is there a problem with a motor that is coming to stand still, without breaking?

The fact of increased motor current seems inessential to me.

Hi Rudy, You are right..!! As you say the the surge is due to regeneration from the motor. I had a 2sec deceleration time programmed, but I "DONT" need to extend the stopping period, so obviously the best thing to do is to reduce the deceleration time to zero. this I've done so we'll see how this goes. Incidentally it would be better to stop it sooner with injection braking, but the manual is difficult to follow. There is no provision for a brake resistor, but I understand there is a capability to achieve braking up to 20 %

Referring to parameter F-20 and it's, 8 sub-parameters can anyone explain more fully the various terms referred to...? Incidentally, the unit is a "110HFE"

Thanks, Norm.

Hello,

For simplicity, let us use the manual that you find in this link; http://www.clrwtr.com/PDF/Hitachi/Hitachi-J300-Drive-Manual.pdf

On page 12-8 you find the explanation for parameter F20.

This is a parameter to decelerate the motor by applying a DC current that is send into the winding.

Generally, you can stop a motor in three ways.

1) You can use a mechanical brake.

2) You can let the motor work as a generator during deceleration, and burn the breaking power in a resistor; (this is the way that is best for your application).

3) You can inject a DC current in to the motor windings and creating a still standing magnetic field in the motor. This means the rotating magnetic field is still there but does not rotate any more. The rotor that is still slowing down will feel this magnetic field and a current will be induced in the rotor bars. This induced rotor magnetic field will further slow down the rotor.

The parameter F20 is controlling this type of breaking.

Mostly it is used for short time braking to hold the rotor in place during still stand.

example when a elevator is coming to stop, the motor speed is decreasing to zero, but during the short period( 0.5-2 seconds) that the motor speed is zero but the mechanical break is not yet activated, on can use the dynamical break option.

regarding parameter F20

Option DC braking selection is used to select whether you will use the DC injection braking or not.

Option DC braking type selection.

If Level is selected, the breaking will go on as long as the command dc braking is selected, (mostly by means of an input that is programmed as DC breaking command. parameter 6 programmed in intelligent input terminal C0-C7 )

If Edge is selected, the DC breaking will go on as long as programmed in parameter DCB STOP -T

Option DC braking frequency selection. During slowing down, the DC breaking will only start if the momentary speed (frequency) is below the programmed frequency. It tels when to start with DC injection, during slowing down.

Option DCB V-STA and DCB V-STP, these give you control over the DC voltage level that is send to the motor. If the DC voltage is higher, the breaking torque will be higher.

You can select a different torque during start and stop.

(Keep in mind the maximum allowable motor current and the warming up of the motor winding.)

Option DCB T-STA and DCB T-STP, this parameter gives control over the time the DC breaking is going on. (It works only when the option EDG is selected in option DCB KIND)

regarding the use of a breaking resistor.

The J300-110HFE, does not have an internal transistor that can control a breaking resistor.

So you have to use a breaking system that consist of

- a breaking resistor

- a breaking chopper

- a circuit that senses the voltage at the buffer capacitor and than decides to activate the breaking resistor.

This breaking module is to be connected to terminals P and N.

You can use a TAE chopper BC 4.1 for this purpose.

http://www.motorsystems.com/docs/im_taebc.

Good luck

information given without any liability

Hi Rudy,

Thank you so much for your help..!! Regards, Norm.