GS3 drive frequency command and DI signals

I am getting ready to use gs3 drives for ventilation.

I am either going to use 4-20ma or modbus to control the frequency under normal operations.

-Normally, I will use run/stop DI to run the drive or coast to stop.

-I want to setup 2 other DI to either fast ramp the drives to 0, or run full out 60hz.

So normal, DI A run/stop, Frequency command either 4-20 or modbus.

- DI B will fast stop the drives regardless of run/stop and frequency command.

-DI C will run to 60hz regarless of run/stop and frequency command.

Is that doable with the gs3 drives?

I've only used the GS1 and GS2 drives, but the GS3 seems to be the same. I might have some time tomorrow to experiment with a GS2 drive I have on the shelf.

Unfortunately, I don't think you can override the 'run' input. That input will need to be ON for your external 'ramp to max or zero' inputs to function. When the 'run' input goes off, the drive will coast to stop.

Overriding the speed with digital inputs is easy, just setup your inputs to select the 'multi-speed' values (P5.x), with one set to zero, and the other to 60Hz. It will immediately ramp to the selected speed using the accel/decel values, and ignore your analog speed reference.

If you don't want the 'run' input to remain ON when you externally command zero speed, you could use one of the outputs to signal when the drive has reached zero speed (i.e. P3.11 set to '3'), and use that to remove the 'run' command once the motor stops.



-Eric

Ok I think I've figured out what I will do. Check that I am right.

Firstly, I don't think i will really need two different accel/decel ramps. I will set the accel/decel to 5 secs or so since these drives will be running ventilation fans.

Under normal operations, I want to control the drives via Modbus from my PC.
When a fault A but not B occurs, I want the drives to run 60Hz regardless of Modbus command. If a fault B occurs I want the drives to run to 0hz regardless of Modbus command or fault A. I will take car of the Fault A/B interlocking via relays, PLC, and safety relay logic.

So on to settings.
Source commands:
P3.00 = 1st source command = 03 =RS485
P3.31 = 2nd source command = 01 = ext control key pad enabled

Freq sources:
P4.00 = 1st source of Freq = 05 = RS485


Multi-Function inputs:
P3.01 = Multifunction input terminals DI1-DI2 = 01 = DI1-Run/Stop, DI2 - Rev/Fwd
P3.02 = Multi-Function Input DI3 = 19 = 1st/2nd source select (N.O.)
P3.03 = Multi-Function Input DI4 = 03 = Multi-Speed Bit 1
P3.04-P3.10 = 99 = Input Disable.

So under normal ops,

Normal Operations
RS485 commands for start/stop and speed.
DI1 = OFF does not matter
DI3 = OFF 1st source select
DI4 = OFF Multi Speed

Fault A (Purge request) and not Fault B (Flame detect)
RS485 commands ignored
DI1 = ON RUN
DI3 = ON 2nd source select
DI4 = ON Multi Speed = Will run to 60Hz

Fault B (flame detect)
RS485 commands ignored
DI1=OFF STOP (will ramp to stop if previously running)
DI3= ON 2nd source select
DI4= OFF (drive will ignore anyway)


Seem correct??

Thanks
Garrett

Since you've decided to use modbus for normal operation, you should be fine. Looks like you've covered everything.

EDIT: I usually set P6.03 to '1' to inhibit reverse operation.



-Eric

Eric Nelson said:

Since you've decided to use modbus for normal operation, you should be fine. Looks like you've covered everything.

EDIT: I usually set P6.03 to '1' to inhibit reverse operation.



-Eric

Click to expand...

Thanks!