How to achieve WITS Self-Certified and Verified Status

The following document is intended to guide WITS-DNP3 Field Device and Master Station vendors through WITS PSA accreditation process.

 Accreditation Levels

Vendors may choose one of two levels of accreditation for their products:

WITS Self-Certified - Tests will be conducted by the vendor themselves using an appropriate test harness / simulator, WITS Field Device or WITS Master Station.

 

The product must be tested with a device which supports the same version of WITS. It is acceptable to utilise either the WITS PSA Test Specification (purchased separately from the WITS PSA at www.ukwits.org) or the vendor’s own equivalent test specification. The WITS PSA reserves the right to reject an application if the vendor’s own test specification does not comply with the WITS Compliance Testing Manual (available from www.ukwits.org).

 

WITS Verified - The vendor must prove product interoperability by testing the Field Device or Master Station against products from a separate development entity to ensure a higher level of assurance.

 

The product must be tested with a device which supports the same version of WITS. The WITS PSA Test Specification must be used (purchased separately from the WITS PSA at www.ukwits.org).

 

Devices can achieve Verified and Self-Certified status at any WITS Protocol revision if they fulfil the acceptance criteria. The WITS Device Catalogue on the WITS PSA website will list the highest protocol revision level that every device has achieved for each status.

 

It is recommended that new products wishing to claim WITS-DNP3 compliance complete full Verified status testing.

 

Accreditation Requirements

 

WITS Accreditation requirements
Equipment type to be tested	WITS Self-Certified	WITS Verified
Field Device	Tested by the vendor themselves	Tested with 2 verified Master Stations.
Master Station	Tested by the vendor themselves	Tested with 3 verified Field Devices.

 

Process for Claiming Accreditation

 

1. Become a member of the WITS Protocol Standards Association.

2. Complete the appropriate tests using either the WITS PSA Test Specification (available for purchase from the PSA at www.ukwits.org) or with an equivalent test specification that will fulfil the requirements of the PSA.

3. Download the appropriate “Self-Certified” or “Verified” application form from the members-only section of the WITS PSA website or use these links (note: members only access):

Application for Self Certification of a WITS compliant Field Device

Application for Self Certification of a WITS compliant Master Station

Application for Verification of a WITS compliant Field Device

Application for Verification of a WITS compliant Master Station

1. Send the completed form together with a copy of the vendor’s own test specification (if used) and any other required documentation or ancillary files to the WITS PSA Secretary.

2. The WITS PSA Secretary:

 

1. Checks the Application form for completion
2. Circulates the form to all members of the PSA Technical Subgroup for comment & review
3. Issues an acceptance/rejection letter to the applicant as appropriate
4. Updates the website

If the application is successful, the vendor may display a WITS Self-Certified or WITS Verified logo on accredited products and their associated literature.

Details of the accredited product are displayed in the Device Catalogue on the WITS PSA website including the current verified and self-certified version status for other vendors and prospective customers to view.

 

Please note that the WITS PSA does not conduct tests themselves, nor do they endorse vendor’s test results. It is incumbent upon prospective buyers to ensure that the equipment fulfils their specific requirements.

 

Future Protocol Developments

The WITS protocol is in continuous active development. New products should be developed against the most recent set of WITS Application Notes, claim compliance at the current WITS protocol version and use a current test specification.

 

Incremental changes to the major protocol revision level (e.g. 1.x->2.x) are assumed to involve significant changes to the software or system of a Field Device or Master Station. These may include significant new functionality, major changes to the protocol or large scale additions or changes to the protocol documentation. As a result, vendors wishing to claim compliance to an updated major specification change are recommended to complete full “Verified” status testing of their product.

 

A minor protocol revision (e.g. x.1->x.2) is assumed to involve minimal or minor changes to the software or system of the field device or master station. These may involve small changes or additions to protocol functionality or clarifications to the protocol documentation. Therefore, once Verified status has been achieved at a given major protocol revision level, it is recommended that products only perform Self-Certification tests on further minor revisions of the protocol standard as needed.

 

Example case

WITS-DNP3 Version implemented by product (Major.Minor)

V1.2 Product undergoes the WITS Self Certification procedure.

Product identified in the device catalogue as:

‘Self certified at V1.2’

V1.3 Product Verified against this version as defined by the WITS Compliance Testing Manual.

 

Product identified in the device catalogue as:

‘Verified at V1.3, Self certified to V1.2’

 

V1.4 Product does not implement this version of the protocol.

 

Product identified in the device catalogue as:

‘Verified at V1.3, Self certified to V1.2’

 

V1.5 Product undergoes the WITS Self certification procedure.

Product identified in the device catalogue as:

‘Verified at V1.3, Self certified to V1.5’

 

V2.0 This is a major release, however the product does not implement this version of the protocol.

Product identified in the device catalogue as:

‘Verified at V1.3, Self certified to V1.5’

 

V2.1 This is a major release and requires mandatory testing as defined by the WITS Compliance Testing Manual to achieve ‘Verified at V2.1’ status. If a vendor decides not to Verify, once the product has completed the WITS Self certification procedure the device remains:

‘Verified at V1.3, Self certified at V2.1’.

 

WITS – Device Manufacturers Name Strings

 

The WITS-DNP3 Application Notes state:

 

The WITS group will define the device manufacturer names that are used by each vendor. This is to ensure that compliant Master Stations can easily determine the Field Device type in cases where different manufacturers have chosen similar product names for their hardware. Vendors wishing to be WITS compliant will need to apply to the WITS group for their unique vendor name string with a maximum of 8 characters.

The rules for constructing the name strings are:

 

• Up to 8 characters in length
• Consists of alphabetic characters A to Z
• Upper or lower case (upper case preferred)

 

The current list of device manufacturer name strings is:

 

Name string	Vendor
ABB	ABB Limited
ITTFLYGT	ITT Flygt (now Xylem)
MSPHERE	Metasphere Limited
MULTRODE	MultiTrode UK Limited
Radcom	Radcom (Technologies) Limited (now part of Halma Water Management)
SCHNEIDR	Schneider Electric Limited
SERCK	Serck Controls Limited (now part of Schneider Electric Ltd)
SERVELEC	CSE-Servelec Limited
TECHNOLG	Technolog Limited
BRODERSN	Brodersen

 

New vendors must obtain their name string by applying to the Secretary at ukwits.org

 

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