Communication Protocols

J

Thread Starter

Jas

Is DNP3 Protocol a property of GE Harris or is it open? Which is better, IEC 608750-5-104 OR DNP3? One should opt for IEC-5-101 OR IEC-5-104?
 
K

Karlheinz Schwarz

Hello All,

> Is DNP3 Protocol a property of GE Harris or is it open? Which is better, IEC 608750-5-104 OR DNP3? One should opt for IEC-5-101 OR IEC-5-104?

The first question is easy to answer: The dnp user group's web site says:

"DNP3 was developed by Harris, Distributed Automation Products. In November 1993, responsibility for defining further DNP3 specifications and ownership of the DNP3 specifications was turned over to the DNP3 Users Group, a group composed of utilities and vendors who are utilizing the protocol."
http://www.dnp.org/about/index.asp

There are multiple answers to the second question (DNP3 or IEC 60870-5-104?) depending whom you ask. A technical comparison of the two can be found under: http://www.nettedautomation.com/news/n_51.html

This comparison will help you at least to understand the commonalities and differences.

The question IEC 60870-5-101 versus IEC 60870-5-104 is easy to answer: the 104 is almost the same as 101 BUT 104 message (ASDU) exchange is over TCP/UP.

The real interesting question is: What will be the future standard in telecontrol and - more general - in power systems automation? A new standard just arrived: IEC 61850 (Communication networks and systems in substations). Read what independent experts like John McDonald from KEMA recomment: "If your timeframe is one to two years, you should consider IEC 61850 and UCA2 MMS as the protocol." [Remark: UCA2 MMS is a crucial input to IEC 61850; UCA is now an umbrella: IEC 61850, ICCP/TASE.2, ...]
www.energypulse.net/centers/article/article_display.cfm?a_id=408

Gustavo Brunello from General Electric wrote recently in an article titled MICROPROCESSOR-BASED RELAYS AN ENABLER TO SCADA NTEGRATION: "The flexibility provided by the IEC61850/UCA-MMS protocols has the potential for saving millions of dollars in development costs for utilities and manufacturers, manufacturers, since it eliminates the need for protocol converters and lengthy, complex database mapping when integrating devices from different manufacturers..."

www.gepower.com/corporate/en_us/aboutgeps/2003releases/020503.pdf

A first public draft "companion" standard to IEC 61850 has recently been published by IEC: IEC 61400-25 (Communications for monitoring and control of wind power plants). This standard relys on IEC 61850 and extends IEC 61850 mainly in the following two areas:

1. adds a comprehensive wind power plant information model including current process, statistical, and historical information of some 150 "information points" like "rotor speed".

2. adds to the MMS mapping (IEC 61850-8-1) other mappings: to IEC 60870-5-104, OPC XML-DA, web services, and DNP3 (keeping the information models!!)

More questions? Please contact me at [email protected]

Best Regards,
Karlheinz Schwarz
Schwarz Consulting Company (SCC)
 
P
DNP3 is an open protocol with a DNP User group at http://www.dnp.org/

DNP3 is a more comprehensive protocol than 101 or 104. DNP3 have the following features that 101/104 does not have.

- Read unlimited multiple objects in a single read commmand.

- Unsolicited data operation.

- Report by Exception operation, can transfer large amount of data even in low bandwidth situation.

- Support Serial/Modem/Radio and Ethernet (TCP or UDP) natively

101/104 can only read and write to one object at a time.

UCA2/IEC 608150 is an even more advanced open protocol than either DNP3 or 101/104. UCA2 clients are easier to configure and use than DNP3 or 101/104.

Regards

Philip Wong

[email protected]

http://www.ioserver.com/
 
M

M. Harisman - Integra Teknik

Please visit : www.dnp.org

DNP3 was developed by Harris, Distributed Automation Products. In November 1993, responsibility for defining further DNP3 specifications and ownership of the DNP3 specifications was turned over to the DNP3 Users Group, a group composed of utilities and vendors who are utilizing the protocol.

DNP3 is an open and public protocol. In order to ensure interoperability, longevity and upgradeability of, protocol the DNP3 User Group has taken ownership of the protocol and assumes responsibility for its evolution. The DNP3 User Group Technical Committee evaluates suggested modifications or additions to the protocol and then amends the protocol description as directed by the User Group members.


M. Harisman
www.integrateknik.com
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In many ways DNP3 is more comprehensive than IEC 101 or 104. However, also it might be worthwhile to check out the availability of vendor and user support for the protocol you choose in your region.

I have seen more support for 101 in the asia-pac region than the use of DNP3. Many or almost all new tender specs coming out talks about iec 101, where-as in US, i feel there is more following for DNP3.

prasanth
kalkitech
 
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