VLT5000 Remote Start Problem

[Rheinhardt]

Hi Guys,

I have a very strange problem , we drive a VLT5000 using profibus intterface and PPO 8 Type. When i issue a start command my contactor pulls in but my drive does not ramp, it simply remains at low current. I can change my reference from the PLC and it works fine. But it seems not to start the Ramp. When i start the Unit in Hand from the local panel it ramps up fine.

Any ideas will be helpfull.

 

[Poet]

You can check the following:
- the reference to the speed loop is selected to be from the PLC
- the maximum frequency might be too low
- the reference set from the PLC might need some scaling before reaching the drive

Also check, if present, any warnings or alarms on the drive, when it is running at low speed.

 

[Rheinhardt]

You can check the following:
- the reference to the speed loop is selected to be from the PLC
- the maximum frequency might be too low
- the reference set from the PLC might need some scaling before reaching the drive

Thank you for your quick response.

1. My reference is set to [1] Remote

2. Maximum Frequency
--When I start it from the LCP on the unit it works fine

3. The reference i enter from the Scada is displayed correctly on the Danfoss LCP and i can see it changing when i change it remotely.


After i set the minimum RPM and i give it a start it Ramps up to minimum RPM 600RPM and stayes there my max is set to 1500RPM and my reference at 76,2%

 

[Poet]

Can you check if the reference value is reaching the controller? and what is the output of the controller inside the drive?