BRX Series PLCs (Stackable Micro Brick) Videos

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The GS Series VFDs from AutomationDirect are

already pretty easy to use with a DoMore PLC. You can either connect them via multi-drop

RS485 OR use the EDRV100 Ethernet to serial converter so you can talk to the drives via

an Ethernet network. In both cases you would use the DoMore Modbus

commands to read and write to the drives. Thatís pretty easy, but every time you want

to do anything with the drive you have to go through the whole send a command, wait

for the command to finish, verify the command ritual, to ensure robust drive control, right? Wouldnít it be great if you could just control

the drive with some reads and writes to local memory and have the DoMore take care of all

the tedious stuff for you? Weíll, guess what, thatís exactly what the

Ethernet I/O does! You just enable the Ethernet I/O feature and

now you control the drive as if it were simple local I/O by reading and writing to a built

in GS Drive Structure. Letís take a look. Were using the same hardware we had in the

quick start video: A DoMore Base, an EBC100 Slave, a Terminator Slave and the EDRV100/GS

drive combo that we want to talk to in this video. Check out the Quick start video to see how

to set things up, but really all you do is enable the Ethernet I/O feature here ñ by

checking that check box ñ Click on Ethernet I/O master, automatically scan the network

for available hardware, and select the items you want to talk to. My system is already setup, so weíll just

say OK. And thatís it! My GS Drive now appears to my program as just

another local device. If I look at my memory tree over here, I can

see under GS eDrive a GS-Drive structure ñ thatís for the new GS Drive I just added. If I had eight drives out there, I would see

8 structures. If I want to see all themembers of that data

structure I just click on this plus sign and you can see all the things you can access

on that GS Drive. You can set the speed of the drive, run the

drive, you can set the direction of the drive, you can use some of these block transfers,

watch the output current, the output frequency, all kinds of things. Well, accessing that is as simple as bringing

up a dataview, and typing it in down here. The name of that guy was dollar sign GS 120,

and suppose I want to monitor the output frequency. Well, there it is. Suppose I want to be able to run and stop

the drive. Well, same thing. I get my structure, dot, RunCommand. Suppose I want to set the speed of the drive. Well, same thing. GS Drive, dot, and if I want to scan down

the list I can do that, and thereís my speed reference right there. What if I want to set the direction of the

drive? Same thing: GS Drive, dot, Direction. Well, letís try it. Letís go ahead and put the PLC in RUN mode. Iím gonna set my new speed to 50 Hz. Thereís an implied decimal, so I need to

put 500 in there. And I want the drive to start running. So I just put a 1 here and write it out and

sure enough, I see my output frequency slowly ramping up to 50 Hz Ö I have a long acceleration

time setup right now so you can see this ramp up. If I put a zero I here, that says stop the

drive, and sure enough the drive ramps down to zero. So think about it Ö weíre actually controlling

a remote drive via local reads and writes to the elements of this data structure, which

we can also see in our memory tree up here. The DoMore takes those values and does all

the cumbersome Modbus stuff in the background for us ñ how cool is that? Iím doing this via the Dataview just to show

you all of this stuff is sitting there ready for your ladder program to use however it

wants. By the way, side note here ñ if you donít

see the GS Drive structure under the memory category in yur tree over here? That means you have it sorted differently

than I do. If you click the button here you can sort

the memory lots of different ways ñ Iím using this method right here. If you pick one of these other ones, the GS

Drive structure is still there, But you may have to dig a little deeper to find it. Now one thing to keep in mind is this structure

right here only has the commands that you commonly need quick access to. Like RUN, STOP, Setting the frequency, monitoring

the frequency, all those things. Well, what if we want to change a parameter

that isnít in this data structure like the acceleration time for example? Normally we would do a mod bus write or just

enter it directly into the drive via the front panel buttons right? And since we usually set lots of parameters

just to ensure everything is exactly the way we want it, that equals lots of Modbus reads

and writes and/or lots of manual entries. Wouldnít it be great if you could do you

drive initialization with just one command? Well, guess what, Ethernet I/O has dedicated

GS Drive commands that do exactly that. For simple example letís just setup the basic

drive parameters for this drive. Well, thatís easy. Come over here, and I want the GS register

write command. If I double click on row 1 here, Look at this

ñ hereís a listing of all the possible drive commands you might want to use. Itís a great handy reference, but it also

helps fill in the blanks for you. So, weíre going to do these parameters right

here. The nameplate voltage ñ if I click on that,

look what happens. It tells me the range of possible values for

that parameter, a description of the parameter, a place to put my data, which I want that

to be 230 volts, and what parameter thatís going to go in. There are no implied decimal places and the

default value for this is 240. Awesome. Letís do another parameter. Double Click on the row. I want to do the motor base frequency. Well, I can see thatís 50, 60 or 400 Hz. I know I want mine to be 60 hz. Thatís going to go into parameter 2, the

motor base frequency. There are no implied decimal places ñ thatís

good. And my default value is 60. Great. Letís do another one. Letís do the amps factor this time. I can see the rated amps can go from .3 to

1.0. I see the name of the parameter. But look here, the implied decimal palces

ñ thereís one implied decimal place. So if I want to set this to 1.0, that means

I need to put a 10 here. So how cool is that? All the information you need to correctly

set a drive parameter is right here in front of you. And if you are still not sure, look at this,

there are two buttons here that will take you directly to the specs or the GS drive

manual. I can pop up the manual directly from the

Automation Direct website, Look up the AC drive parameters, and find out everything

I want to know. Keep in mind ñ thatís a direct link to the

AutomationDirect website. So these only work if you have access to the

internet. But regardless, how easy is this? All the parameters are right in front of you. Just click on the one you want, fill in the

blanks and say OK. And I can keep on going. You can add up to 50 parameters in a single

instruction. The instruction will execute all of those

parameters, take care of all of the modbus reads and writes for you, and when itís done,

it will set a bit which Iím using C0 for. On error it will set a different bit - which

my personal preference is C99 ñ and I say OK. Well, thatís it ñ in one instruction I can

configure my Drive. And look at this, becasue this instruction

is edge triggered, I donít even really need a contact here, right? The first time the program runs, this will

see the rising edge. It will execute that and it will never execute

it again. Or I could put a contact here and say only

do this on first scan. Or I could even drop this into an initialization

routine that has a bunch of these for all of my different drives. Lots of things I could do, but it is all setup

to make it easy for you. The main thing is, you can do your drive configuration

with one line of ladder code and then operate the drive doing local reads and writes to

this data structure. No modbus reads or writes anywhere. How about that? Well, that should be enough to get you started

with using GS Drives via Ethernet IO on the DoMore. Be sure to check out the other videos in this

series for more tips on using the DoMore PLC. And donít forget ñ Automation Directs tech

support is always FREE and you will talk to a real live person here in the US within minutes. Got a question? You can call, e-mail, or even do on-line chat

during regular business hours. Whatever you prefer. Spend LESS. Do MORE. From Automation Direct.