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Form Letter for European users

Original writing : 31 March 1995
Latest revision : 18.May 2021

Dear ATP EMTP-interested party:

The form letter now being read is a specially-modified version of the North American form letter LICENSE.ZIP. It is used in Europe to license and distribute ATP materials with the approval of:

Co-Chairmen of Canadian/American EMTP User Group
Dr. W. Scott Meyer Dr. Tsu-huei Liu
3179 Oak Tree Court
West Linn, Oregon 97068

The Alternative Transients Program (ATP) is the most widely used version of the Electromagnetic Transients program ( EMTP ) in the world today --- by far! In no small part, the acceptance of ATP is due to its availability to nearly
everyone in the world free of royalty, and its compatibility with the computers of most common interest.

EMTP was developed in the public domain at BPA (the Bonneville Power Administration) prior to the commercial initiative in 1984 by DCG (the EMTP Development Coordination Group, with which BPA has had no connection since expiration of the associated agreement on the last day of 1987) and EPRI (the Electric Power Research Institute of Palo Alto, California, USA). Whereas BPA work on EMTP remains in the public domain by U.S. law (FOIA, the Freedom of Information Act),
ATP is not in the public domain. It is, however, available free of all charge to anyone in the world who has not participated voluntarily in the sale or attempted sale of any electromagnetic transients program (hereafter called "EMTP commerce"). Those who have engaged in EMTP commerce, but now wished they had not, may contact the Can/Am user group to learn about conditions of possible pardons.

Membership in EPRI, CEA, or CRIEPI (the latter two being DCG members) does not, by itself, disqualify any organization from access to ATP, it is important to note. Nor does use of the DCG/EPRI EMTP that is licensed and distributed by EPRI. This is the significance of the adverb "voluntarily." Clearly, few if any EMTP users control the high-level politics that are associated with membership in national organizations such as EPRI, CEA, or CRIEPI,
so membership alone will not be held against anyone. No problem exists provided no significant resources (e.g., money, technical advice, computer work, advertizing) have been contributed directly to the joint DCG/EPRI commercial project.

Commercial competitors no longer are excluded from access to ATP. This is a big change from earlier years. As explained in the January, 1992, issue of the newsletter (story on pages 8-9), the Can/Am user group has decided to approve the disclosure of ATP to, and use by, any commercial developer of any competing electromagnetic transients program on the same terms as work of that commercial developer is made available to the general community of ATP users. This is reciprocity.

MS Windows is used by the average Intel-based PC, and ATP is generally compatible. Salford DBOS should work with Win 3.x, Win95 and Win98, but not WinNT. For Microsoft Windows versions NT, ME, 2000, XP, Vista and Windows 7 use either GNU Mingw32 ATP or Watcom ATP (the same executable runs correctly under Windows 95, 98, too). GNU ATP for Linux is yet another alternative for Intel PCs.

Each authorized user of ATP must agree not to disclose any ATP information to unauthorized persons and / or organizations. A non-disclosure agreement to this effect must be signed by each potential user, and approved by the user group, before access to ATP information will be granted. The form is attached as sheet number 2 of this letter.

The sharing of ATP materials among authorized users is encouraged. If one authorized user has newer or better materials than a second, the first user is encouraged to share with the second. 

Consultants and manufacturers who want to use ATP are encouraged to do so provided there is no misrepresentation, particularly to customers. In the case of commercial design and / or consulting, this means that clients or potential clients must be notified prominently, and at the earliest opportunity, about the EMTP version that is being used (ATP), its royalty-free nature, and who licenses its use. If the name DCG or EPRI is mentioned along with EMTP, it must be explained that ATP has no connection with the commercial product that is licensed by EPRI. Passing this form letter to a client is an easy way of informing him.

Education is another activity that can profit from ATP use, but only if several rules are carefully followed. First, there must be no misrepresentation of ATP (same requirement as the preceding paragraph) to potential students in any advertizing for the course. Second, prior to the disclosure of any ATP materials to any student, that student must be supplied with a copy of this form letter, he must submit licensing, and his application must be officially validated. Third, regarding access to ATP, all course faculty are subject to the same restrictions as students. If printed advertising for a course mentions ATP, it is strongly recommended that wording be checked with the user group prior to reproduction in order to avoid any possible misrepresentation.

Licensing to use ATP is free of all charge for all who have not engaged in EMTP commerce. Once one is licensed, he is authorized to obtain ATP materials from anyone (sharing among users is encouraged). E.g., any ATP-licensed person in the world can acquire materials from the European EMTP-ATP Users Group e.V. (EEUG), which is a registered association according to German law.

BPA is cooperating with the Can/Am user group for the noncommercial development and use of ATP, readers are reminded. As an agency of the U.S. government, BPA is accessible to the general public, and BPA performs some services that are valuable to the EMTP community. For example, BPA shares EMTP information with both foreign EMTP user groups and selected cooperating individual program developers and users. All inquiries
about EMTP (nothing else, please!) can be addressed to:

Tsu-huei Liu or W. Scott Meyer
P.O. Box 3621
Portland, Oregon 97208
E-mail (Internet): canam@emtp.org

Can/Am EMTP News is the name of the quarterly newsletter of the user group. The issues are dated January, April, July, and October, and all lengths since 1993 have been 20 pages. The newsletter is available free of charge to anyone, whether ATP licensed or not. Disk files began as WordPerfect 5.1 format, but later were switched to MS Word (.DOC files). Finally, only Adobe PDF (Portable Document Format) files are released to the general public. These are readable using the free Adobe Acrobat Reader (click on www.adobe.com/go/getreader to download the latest version). Newsletters are available from several storage sites on the Internet such as the web site of the European EMTP-ATP Users Group (www.eeug.org) or on the campus of Kyoto University in Kyoto, operated by the Japanese ATP User Group (www.jaug.jp). Normal publication as just described ended with the April, 2004, issue. Finally, the European user group EEUG operates a free electronic bulletin board using address atp-emtp-l@listserv.dfn.de.
Prof. Harald Wehrend, University of Applied Sciences, Kiel, is responsible for the operation of that mailing list. This is for ATP-related announcements, questions, answers, etc. The EEUG has published regularly EEUG News from 1995 until 2001, which contains besides technical papers, reader's corner and hints for program usage.
Dynamic dimensioning allows actual table space of ATP to be fixed by the user at the start of execution within some very large limits. This began in mid-October of 1993. Previously, table sizes were fixed as the program was linked, resulting in names such as TP3 or TP20. These are history. Now, the single TPBIG.EXE satisfies most users.

Object files are available for those who have acquired the free GNU FORTRAN compiler g77. Object files are more flexible because they permit:
1) modification of limiting table sizes;
2) the connection of user-supplied source code;
3) compiled TACS; and 4) selective correction of program errors.
For further details, consult the JAUG (Japanese ATP User Group) storage at Kyoto University and Kisarazu National College of Technology. This, in turn, requires a password

that is available from the EEUG Association for users licensed by the EEUG.

Other computers (not Intel-based) are compatible with ATP. In fact, almost any modern computer of practical interest has been proven to be compatible (more than 30 distinct systems have been tested). ATP is supported on other computers in various places. For members of EEUG, the transfer can be arranged by the user group. Others are referred to the Can/Am user group.

Cordially yours,

c/o Prof. Dr.-Ing. Harald Wehrend
University of Applied Sciences Kiel
Faculty of Computer Science and Electrical Engineering
Grenzstra├če 5
D-24149 Kiel
E-mail: wehrend@eeug.org
EEUG Web page: http://www.eeug.org

It is recommended to print this form letter for your own records before proceeding with the ATP licensing agreement or EEUG order form.

If the preceding form letter has not yet been read carefully, do this before proceeding. Should any detail be unclear after reading, contact the user group for clarification prior to the submission of an application for free ATP licensing (next). To order ATP materials from the EEUG, ATP licensing is necessary.

ATP Licensing Agreement for European Users



The undersigned certifies that he has not participated substantially and voluntarily in EMTP commerce (defined to be "the sale or attempted sale of any electromagnetic transients program").
If ATP usage is to be organizational rather than personal (i.e., if ATP materials are to be used by, in, for, or on behalf of, a company, university, etc.), the undersigned certifies that the organization being licensed has not participated in EMTP commerce -- nor has any employee, contractor, or other agent who would be granted access to ATP materials.
The undersigned acknowledges that the ATP materials being requested are without any guarantee or warranty, either expressed or implied, and that no author, licensing agent, or distributor of such materials will be held responsible for any damage that might possibly result from the use or misuse of ATP materials. The requester acknowledges and accepts sole responsibility for his usage of ATP materials.
The undersigned certifies that the unique informational content of the ATP materials will not be disclosed to anyone who is not similarly authorized to have such information.
The undersigned certifies that the source of ATP materials or computer results will not be misrepresented to others. That is, there must be open disclosure of the computer program being used, and the fact that it is a royalty-free product for nearly everyone.
Any subsequent violation of the conditions of this sheet or the preceding form letter will result in an immediate termination of this license to use ATP materials. Should this happen, the undersigned certifies that all available copies of ATP materials either will be promptly returned to the user group, or will be promptly destroyed. The undersigned realizes that authorization to use ATP materials ceases the instant of the first such violation.
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ATP licensing form with data entered by you will be built in the browser automatically after submitting this form. Please print that form, sign and send it by conventional surface-mail (fax is not accepted!) to:
c/o Prof. Dr.-Ing. Harald Wehrend
University of Applied Sciences Kiel
Faculty of Computer Science and Electrical Eng.
Grenzstra├če 5
D-24149 Kiel

About Us

This site has been established for the users of the royalty-free ATP version of the Electromagnetic Transients Program (EMTP). The ATP license is free for nearly everyone accepting the rules expressed in written form when filling the license form.

The site is maintained by the Europan EMTP-ATP users group. There are other related web-sites:

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