M340 love

Love this plc and software now.

Anyone else?

I feel I could answer any question on this device now.

No!

We switched from using Quantum with 4-5 remote or distributed IO racks (which were Advantys or sometimes that Quantum remote IO over coax) to using 4-5 M340 CPUs that communicate with the central one using IO scanning.

The M340 is 1/4 the cost for the CPU and 1/2 the cost for the modules, takes up 1/3 the space in the control panel, and saves us a lot of time in not having to wire to the front of the IO module because of the module terminal block cables and connectors. Those cables are also 1/3 the price of the allen bradley ones.

The M340 has been a game changer for us!

ganutenator said:

Love this plc and software now.

Anyone else?

I feel I could answer any question on this device now.

Click to expand...

Hi!
I have one question (or more)... let me describe my system first.
I'm starting to work with an M340 + InTouch system
Connection is Ethernet
Communication is ModbusTCP
PLC config is with Unity PRO XL
I don't have problems with ModbusTCP from InTouch's side, but I'm new to Unity PRO

Questions:
1) Are M340's I/Os mapped automatically to modbus registers?
2) If (Y): Where is the table that shows this mapping?

Till now I've found info saying (N)... so I'm starting to look at "ADDM" & "WRITE_VAR" functions to map m340's I/Os to modbus.
3) Is this approach correct?
4) Can I get an well commented example of how to do this way?
5) OR the RIGHT way to do this...

For your help, thanks in advance!

I know someone will have a better way, but this is what I did.

(*Bridge Photo Eye 1*)
PE1_Input_Deb (raw_input := %I0.1.7.0,
turn_on_pre := 200,
turn_off_pre := 1,
hmi_force := ForceI[7],
deb_output1 => PE1_clear_deb,
deb_output2 => %MW0.7);

where "PE1_Input_Deb" was an instance of this code in ladder in the image attached.

My personal preference is to address all the IO's using the topological format %Ir.m.c for Rack Module Channel. Then we refer to the PLC IOs on our drawings using the plc#.r.m.c notation.

The r.m.c addresses can be read directly out of the M340 PLC "state ram" memory using not often used modbus addresses and functions for read coil status and read input register. But it isn't obvious because the mapping is done by the PLC. I prefer just to map the IO to normal coils or words myself.

Go to an input module on the rack, then go to the memory tab, and you will see options for mapping topological addresses to state ram. Press F1 to read the help ... and then you will probably decide to just map them yourself in the program instead of hiding the logic in configuration magic buried on a tab 4 levels down the tree.

1. On M340 system it depends of setting of IO- cards. Default is that IO don't have modbus addressing and you need copy IO to modbus variables/addresses on plc code with move-blocks or

input0/r.m.c               variable0/%Mx

--| |---------------------( ) 

commands. For analog there is also pre maded data types which can show also errors of cards

principle is that PLC %Mx adress have modbus address 0x or 1x and %MWx (%MD and %MF) 3x or 4x (double and floats use two consecutive addresses)

2. (Y), double click cards on hardware catalog and select modbus. If you click PLC card, you have there selection show mapping (or something similar which show all used addresses...)

3. No, you need addm, write/read blocks only if you read addresses from another plc or modbus device

4. tell us if you find

5. go to 1.

It would be advisable to open new thread for this

Ok, question: how well does it handle DNP3? What's the price of hardware and software compares to AB?

The DNP3 RTU module was $1800 when I checked a couple of years ago. We use a SEL-3505 for DNP3 instead. It is less than $1000 and talks to SEL relays, DNP3, modbus, can do serial to ethernet, and all data type conversions and mapping between those protocols (and probably more I don't use). Also takes IRIG input and can be NTP server.
Unity pro S (only need S for M340 and M580, XL is required for Quantum) is about $2500 CAD i think.

The main limitations of M340 are 1024 discrete IO points and 256 analog channels per CPU or ethernet remote IO adapter (on 4x12 slot backplanes).

I would say the cost of the M340 IO modules was about 1/2 of what we paid for allen bradley control logix, probably in the same ballpark as compact logix.

V0N_hydro said:

The main limitations of M340 are 1024 discrete IO points and 256 analog channels per CPU or ethernet remote IO adapter (on 4x12 slot backplanes).

Click to expand...

Have you looked M580 CPU's, they use same IO than M340 but can have more IO.

IO scanning is adding ethnernet IO and IO-scanning on Unity. Bad thing is that M340 don't have IO scanner functionality on CPU's inbuild ethernet port. Still 1024/256 is pretty much.

IO scanning is adding ethnernet IO and IO-scanning on Unity

I should have writed:

1024/256 limit can be avoided with using ethernet IO and IO-scanning functionality on one PLC.

V0N_hydro said:

The DNP3 RTU module was $1800 when I checked a couple of years ago. We use a SEL-3505 for DNP3 instead. It is less than $1000 and talks to SEL relays, DNP3, modbus, can do serial to ethernet, and all data type conversions and mapping between those protocols (and probably

Click to expand...

I heard a lot about RTAC and it seems to fill a need, however, I still haven't found anything that can also do Ethernet/IP <> DNP3 without using an OPC server in between.

harryting said:

I still haven't found anything that can also do Ethernet/IP <> DNP3 without using an OPC server in between.

Click to expand...

Our solution at an Allen Bradley plant was to use a digi one IAP to translate modbus to Ethernet/IP and then the SEL-3505 made modbus requests to the Allen Bradley PLCs through the digi one IAP, and the remote GE-D25 RTU could talk to the SEL-3505 on DNP3.

I believe the M580 uses CIP aka Ethernet/IP for the ethernet remote IO so maybe you could use M580 to be or talk to the Ethernet/IP devices with the DNP3 RTU module for bridging Ethernet/IP to DNP3 without OPC?