Disabling RFG for Reverse Direction

Hi gents,

Is it possible to disable RFG for Reverse direction only?

There are all kinds of things that are possible.

However, it may be simpler to simply prevent the reverse input from doing anything.

For example, you can "rewire" the reverse command to always be 0 or always be 1.  Then toggling the reverse does nothing.  The reverse being set to 1 is similar to swapping 2 motor leads, or configuring the drive to run in the opposite direction for a positive RPM input.

Tom_91

Hi gents,

Is it possible to disable RFG for Reverse direction only?

I actually need the reverse run for a specific application mode but without the RFG.

I think I will try with Disabling RFG when Run reverse request is made, this should work.

In the control word for Sinamics drives, Enable RFG, is that the bit you are considering turning off for reverse?

Tom_91

I actually need the reverse run for a specific application mode but without the RFG.

I think I will try with Disabling RFG when Run reverse request is made, this should work.

It's a stand alone unit without any networking, with 3 DIs. One of the DI is reverse command.

RFG enable (it's a dual ramp function) currently is set to "1" permanently.  Based on your previous comment I believe if change the RFG enable trigger to be the inverted input of the DI which requests reverse run it should be able to get the results I want, will try it at some point this week see if it works, unless anyone can see a reason it wouldn't?

The main aspect of the system is that the "deragging/cleanning" is controlled by an independent 'smart' controller rather then the G120 drive control itself, so we need to run in reverse at 100% speed while positive (normal running) condition should adhere to specific ramp function.

0_Einstein

In the control word for Sinamics drives, Enable RFG, is that the bit you are considering turning off for reverse?

Tom_91

I actually need the reverse run for a specific application mode but without the RFG.

I think I will try with Disabling RFG when Run reverse request is made, this should work.

 

how do you manage the 'reverse' command?

Tractor

Off 3, this is a rapid stop command, which could be set to a very low value for the 'de ragging',

P848:0 could be connected/set to r722:5 (this is din5, terminal 17), this needs to be set high for the drive to function; when low the quick ramp down time will be effected.

Some ramp down time will be required, depending upon the size of the pump.

Apologies, talking rubbish here...........it is the ramp up time, in reverse which is necessary, will have a look at that.......

Tractor

Using ‘standard Drive data set, (Parameter 15 = 12).

Analogue setpoint and run command to terminal 5 (DIN0), and inverted setpoint terminal 6 (DIN1).

Switching to CDS 1 for the rapid ramp up. This is triggered by selecting Digital Input 1, setpoint inverted.

P810 = 722:1, selecting Command Data Set 1, for rapid ramp.

P819:0 = 0, copy data from CDS0 to CDS1.

P819:1 = 1, CDS1 target data set confirm

P819:2 = 1, copy CDS, (from CDS0 to CDS1)

P1138:1 = 2900, use fixed value.

P2900 = 10%, fixed value for ramp in CDS1.

Operation:

Close DIN0, ramp to analogue input setpoint using ramp times in P1120 & P1121.

Close DIN0 and DIN1, reverse setpoint enabled, and ramp to setpoint using 10% of the normal ramp setting.

CDS– Command Data Set, this is using two Command Data Sets.

Tractor