What is the best network for PowerFlex Drives

We are going to start a new proyect which involve the use of 5 or 6 drives, an we want to know what is the best network for the powerflex drivers, we also are going to use a Panelview, and its going to be in the same network as the drivers.

I read about the all the drivers use a built in Modbus port, and all the interfaces, use the same speed as the Modbus port use, is it rigth ?

I will not say which one is the best network, but i know for sure that i will never use ethernet/ip, i have used devicenet with excelent results, never use controlnet.

In our applications which don't need fast control of the drives (just sending speed and monitoring for faults) we use Modbus if the PLC has it. We have used DirectLogic units from AutomationDirect and the MicroLogix units from AB. Some of the MicroLogix units need an additional RS232 - RS485 adapter.

All On/Off control is by hard wiring. We have controlled many units in a chain.

We have used the Ethernet adapters which, with multiple drives connected, do use the serial interface between the drives so there is no speed advantage.

I use devicenet on our old PLC5 systems and ethernet/IP on all of our controllogix systems. I have never had an issue with ethernet/IP but I think it is all in the way it is set up. I have all my drives and I/O on one ENBT card and HMI and plant network on another. I also run Hirschmann managed switches. The systems run perfect. Network size is a concideration.

Which comms I would use really depends on the PLC as well as the Drives. Someone mentioned Ethernet/IP. If the PLC is in the Control/Compact logic family then I would use Ethernet/IP. If the PLC is a Micro or another brand I would look at another type.

Really you need to look at everything. PLC, HMI and drives to make this decision. You also need to look at how much data you are going to be moving and how fast you need it to do.

In my experience, Comm's is usually the largest pain in the rear of any project.

All protocals have a way to smack you around and question your sanity.

we are going to control a winch, its from 1950´s or something, so theres no replacement for the components sush a relay and that things, we want to use KISS (KEEP IT SIMPLY ....) jejeje,

The thing is that we are going to use a Controllogix because the customer want a controllogix, but i think we are going to use 50 Inputs and 20 outputs, and controlling the drives with an analog output 4-20 mA, Stop, Forward, Reverse with the outputs from the PLC.

The problem is that, how can i make that the drive just move a little the motor, (i think is the jog funcion), because the operator can select, Foward, Reverse, Stop, and he can make the motor to move slowly with 2 buttons, one for each side (Foward, Reverse).

That is what is making me to choose a network, and try the premier integration, does it really works well?, i mean if i choose a network i would need to buy a Communication card for each drive i choose.

If you have a question post it, and ill reply

The advantage to hardwired control with analog speed reference is that anyone can troubleshoot it, and about any brand drive can be used for a replacement part.

The advantage to using a network interface is that you can perform parameter changes at runtime which might give each drive more flexibility, as well as read more information from the drive, like current, speed, fault codes, etc.

I don't think you will see a response speed or other performance improvement by using Ethernet/IP or Devicenet in favor of analog and hardwiring.

Which model of PowerFlex drive are you using; the 4-series, or the 7-series ?

Winch applications can be tricky if they are hoisting vertical loads or trying to control tension. Or they can be simple, obviously, controlled by a simple drive or variable speed system.

You mentioned "5 or 6" drives; are you controlling several winches, or a co-ordinated set of tensioners, or something else ?

OkiePC said:

The advantage to hardwired control with analog speed reference is that anyone can troubleshoot it, and about any brand drive can be used for a replacement part.

The advantage to using a network interface is that you can perform parameter changes at runtime which might give each drive more flexibility, as well as read more information from the drive, like current, speed, fault codes, etc.

I don't think you will see a response speed or other performance improvement by using Ethernet/IP or Devicenet in favor of analog and hardwiring.

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I agree with Okie... I think a network would be overkill...unless your angling towards a service plan.

But you are already using a Control Logic PLC so an ethernet/ip would be pretty easy to install and get up running...

Bottom line... unless there are cost restrictions...The ethernet/ip would keep you from being painted into a corner if you overlooked a function you needed

Ken Roach said:

Which model of PowerFlex drive are you using; the 4-series, or the 7-series ?

Winch applications can be tricky if they are hoisting vertical loads or trying to control tension. Or they can be simple, obviously, controlled by a simple drive or variable speed system.

You mentioned "5 or 6" drives; are you controlling several winches, or a co-ordinated set of tensioners, or something else ?

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Tha rates of the motor are 0,55 KW, 3 KW, 2.6 KW and 45 KW, i think im going to use series 4 of Powerflex.

Sorry about the translation, what we want to controll is a lathe jeje, its not a normal one, heres a pic jeje



The question is, if i go hardwired, how can i make the motor rotate slow Foward and reverse ??

gtr35 said:

The question is, if i go hardwired, how can i make the motor rotate slow Foward and reverse ??

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Typically you'd set up the drive for two wire mode which menas the discrete signals are maintained rather than momentary.

You will have a stop signal (think enable), a run forward signal, and a run reverse signal. These are digital inputs to the drive, and commonly outputs from your PLC, although the stop signal may be also interrupted by other relay logic.

You will also have an analog speed reference.

You hold the drive stop input true to allow it to run, and make the forward or reverse bits true to choose a direction. When the stop input and a direction input are true, the drive will ramp to the speed reference supplied by the analog signal at the programmed accel rate.

With the default ramp stop mode, if the run forward or reverse input turns off, the drive will decelerate to zero at the programmed decel rate, as long as the stop input remains on.

If you take away the stop signal, the drive will coast to a stop.

If you want a custom accel or decel rate, then you simply ramp the analog signal as you wish.

In some cases it might be preferred to use a bipolar speed reference to control both speed and direction with an analog signal, and a single drive digital input for Run/Stop.

I will go with OkiePC. The bipolar reference makes more sense for this aplication.

Mmancillas said:

I will go with OkiePC. The bipolar reference makes more sense for this aplication.

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The advantages to a bipolar reference:

1) One less relay

2) (Often) faster switching of direction

3) Positioning or velocity algorithms can be simpler...you just calculate the desired output, and send it out the card....if non zero, turn on the Stop signal. The polarity ends up being the same as the polarity of the error between actual and desired, so you don't have to polarize it and choose which direction relay to select.

widelto said:

I will not say which one is the best network, but i know for sure that i will never use ethernet/ip, i have used devicenet with excelent results, never use controlnet.

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Excuse me I meant "I have never used controlnet"

Paul did they call you bipolar?