Yaskawa G7 not getting up to Refrence Speed

We have a new Yaskawa G7 Drive That we Give A refrence Via Profi bus of 100HZ but only runs up to 80 to 85 HZ. Max speed of the drive is 110 HZ and the torque Is set at max 300%.You can see the refrence signal on the Lcd display and it is 100HZ. I know this isnt a PLC question but I thought someone may give some insight.

You need to offer more details about the application.

Normally if the display shows 100Hz then the motor should be running at 100Hz. That said, there may be physical limitations on the system that do not actually allow it to "transfer" that speed proportionately.

A drive can not increase the torque or HP capability of a motor, at some point they decrease as speed increases.

That said a simple example of a problem could be when the drive is running the motor at the desired speed, 100hz in this case, but the system (a conveyor could be an example) "SLIPS" more as the speed increases i.e. once you obtain a certain speed it is incapable, due to mechanical limitations, to go any faster.

rsdoran said:

You need to offer more details about the application.

Normally if the display shows 100Hz then the motor should be running at 100Hz. That said, there may be physical limitations on the system that do not actually allow it to "transfer" that speed proportionately.

A drive can not increase the torque or HP capability of a motor, at some point they decrease as speed increases.

That said a simple example of a problem could be when the drive is running the motor at the desired speed, 100hz in this case, but the system (a conveyor could be an example) "SLIPS" more as the speed increases i.e. once you obtain a certain speed it is incapable, due to mechanical limitations, to go any faster.

Click to expand...

True, but typically if a drive cant run what it is asked to run there should be a speed devation error. I am not getting a devation error or any error!

Some drives have more than one parameter for the MAX Speed

Likely the drive is displaying the speed reference, not the output frequency or motor speed.

The reference could easily be at 100hz and the drive output is limited either by another speed limit setting or by hitting the current limit point.

If the drive were actually putting out 100hz at motor nameplate voltage and the motor was only turning at the 60hz speed, the current would be huge and an overcurrent fault would occur almost instantly.

G7 drives have 3 line displays on the keypad.

They are defaulted to Freq REF, Output FREQ and MOTOR AMPS.

Typically these drives try and provide the amps necessary to get the desired speed and will trip on MOTOR OVERLOAD if it takes more amps than programmed to get the motor up to speed. I do not see this drive running at current limit and limiting speed. If your output speed is less than the set speed, a deviation alarm should be shown.

How are you inputting the FREQ REF. 0-10 volts or 4-20ma?

If you are inputing 4-20ma, it must come in on A2, S1-2 must be moved to ON, the lower switch to the right position to properly recognize the input. Then H3-08 must be set to 2 and H3-09 to 0.

It is 100HZ Via Profibus.

Randy -
I think it is most likely another parameter that
is limiting drive output, as DickDV and 504bloke pointed out.
What happens if you enter a different setpoint via Profibus,
such as 80 hz. Do reference and displayed output match then?

Sorry I forgot about you using coms. I had a time lag between reading and replying.

Did you change E1-03 to get max freq?

What method of control are you using V/F, or Vector?

By only changing E1-04 to 100 hz you should get the 100 hz output with out changing any other E1 parameters.

I suggest you set E1-03 to F and set E1-04 to 100 with no other changes. IF you are in vector mode, the output hz usually is slightly above the reference for slip compensation.

There are gain parameters that can cause you to only get 80% of reference on the output. What kind of amps is the motor drawing?

edit: make sure D2-01 is set at 100%.

randy741985 said:

We have a new Yaskawa G7 Drive That we Give A refrence Via Profi bus of 100HZ but only runs up to 80 to 85 HZ. Max speed of the drive is 110 HZ and the torque Is set at max 300%.You can see the refrence signal on the Lcd display and it is 100HZ. I know this isnt a PLC question but I thought someone may give some insight.

Click to expand...

What is your current draw? Especially if the frequency is fluctuating around 80-85 HZ, it sounds to me, like you are hitting a current limit. There may be a parameter, limiting the frequency by the current output. I have drives like this on a fan application. Set to 60 HZ, they will normally run about 58.

brian

Got IT going, We went to 300% on torque and that took care of it.I havent had tim to post it. My mistake I thought it was set to 300% it wasnt.

Thanks alot for everyones input.