Hello Fellows

I have an Emerson RTU talking to a SCADA server via VSAT and some intermediate Fiber Optic TCP/IP, Ethernet based network before data finally reaches SCADA server. This SCADA server only talks Serial (RS-232).

I am proposing to use Ethernet port on the RTU (programmed to handle TCP/IP Ethernet) to stay Ethernet all the way and use Ethernet to Serial converter at the SCADA server. But I am being told by vendor that I should have data coming out of RS-232 port of the RTU and in addition use a Serial to Ethernet converter before data is fed into VSAT. i.e. use two converters one at each end. I don’t think adding a Serial to Ethernet converter at the RTU end will add any value i.e. why first come out of RS-232 port and then convert to Ethernet as we can go straight Ethernet from RTU Ethernet port to VSAT. But vendor is saying that if data is not originating from Serial port of RTU then SCADA server will not read it.

Your help on this will be appreciated.

Regards
BJ

 

BJ,

It may depend on what protocol you are using. For instance, if it happens to be BSAP, then the serial version and TCP version differ. Using the serial to ethernet converter will effectively wrap the serial protocol in an IP packet and then unwrap it on the receiving end.

If it were a direct Ethernet connection, the protocol would be IBP, not many SCADA host can talk IBP.

Hope this helps!

 

Is it possible, that you are using the wrong SCADA system ?

 

Are there any Serial to Ethernet converters in the market that don’t just wrap serial protocol in an IP packet but do actual conversion to Ethernet where Serial Protocol is actually lost and you can simply connect to a native Ethernet device on the other end?

Thanks in advance:

 

Certainly. But you would need to be specific about the protocols involved, as you are no longer just encapulating "some" protocol in TCP/IP, but actually implementing two independent protocols.

For example, the ETH-1000 gateway (http://iccdesigns.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=ICC&Product_Code=eth1000) converts serial to Ethernet (and vice-versa). The Ethernet and serial protocols are independent of each other (there is no encapsulation taking place). But the question is what are the specific protocols that you need. For example, Modbus RTU (serial) and Modbus/TCP (Ethernet)?

Regards,
Darrin

 

It's a sad fact of automation that there is no such thing as an 'SCADA' Ethernet protocol. So the best option is to find out what protocols your SCADA system can speak natively and are already licensed and then buy a device which can talk that protocol or act as a gateway.

Regards,
Tomy Zacharia

 

You have a basic problem there in that there must be _some_ protocol on top of ethernet. Just putting the bits on the wire wouldn't gain you anything because the "native" Ethernet device wouldn't understand them. Most use all or part of the internet suite of protocols which is why wrapping packets in ip is a reasonable thing to do. Another way of saying this is that you need the same protocol on both ends. So if you could get a 232 to Ethernet converter that talked whatever was "native" to your end device, it would do what you want. But as we have seen from the majors, Ethernet by itself means nothing for either compatibility or interoperability. They simply plopped proprietary protocols on top and it's as useless as any of their private schemes.

Regards
cww

 

might be the anybus serial server will work here:
http://protoconvert.com/GatewayBridge/SerialServer.aspx