2.1
Mode of presentation
(1) The requirements of this Specification are printed in plain type with each paragraph formally numbered. Informal comments, recommendations and explanations which are added only as indications of the means of compliance with this specification are shown in italics. Smaller type is used and each paragraph is preceded with a "*" symbol instead of a clause number.
(2) Mandatory requirements are indicated by use of the verb form "shall" and clauses including such requirements are highlighted as demonstrated here.
(3) Voluntary and preferred requirements or recommendations are indicated by use of the verb forms "should" or "may".
(4) Due to the extent of the differences in format between this Specification and previous PTC 200/- series Specifications, there has been no attempt to retain any clause numbering used previously. Return to Contents
2.2
PTC 101 Electrical Safety Requirements (see also clause 2.8).
TNA 102 Analogue PSTN Line Interface Conditions.
Related Specifications
(1) For any Telepermit application to be successful, the equipment concerned shall comply with the requirements of the following specifications:-
* Specification PTC 101 is currently under review. When published, it will basically call up the joint Australian and New Zealand standard AS/NZS 3260:1993.
* TNA 102 was formerly published as PTC 102.
(2) All Telepermit applications and ongoing product marketing shall comply with the requirements of Specification PTC 100.
(3) As outlined in Specification PTC 100, where any conflict arises between its requirements and those of this product Specification, the requirements of this Specification shall take precedence.
2.3
Marketing features
Some equipment features or characteristics are regarded as purely marketing issues and their requirements are therefore not necessarily dealt with in this Specification. However, in cases where clarification is considered desirable, explanatory notes are provided.
* Although regarded as marketing features, it is a requirement that they be included in the features list referred to in clause 2.4(5) below. Return to Contents
2.4
Specialised services & features
(1) Certain types of products incorporate one or more special features which interact with the Telecom network and which may affect the mandatory requirements of this Specification.
(2) In addition, some products using specialised services have features which are not included in the Sections of this Specification covering the main functional requirements.
(3) Section 11 of this Specification covers the additional requirements for some products described in (1) and (2) above. However, due to the potential range of such features and also the continuing developments in technology, it is always possible for features not to be specifically covered. In such cases, Access Standards will state the necessary requirements.
(4) Use of certain products or features described above may, in some situations, give rise to incompatibilities with other services and/or customer products. In such cases, special conditions may need to be set for the grant of a Telepermit.
* There are many cases where an individual product satisfies Telepermit requirements for connection to a PSTN line when no other products are connected, but fails to operated correctly when another Telepermitted item is also connected to the same line.
(5) It is a mandatory requirement for all Telepermit applications that a complete list of functions/features for the product concerned be included. This may be part of a test report or as a separate list associated with the application form.
2.5
Variants of the same basic design
(1) Where the same basic design (particularly any electro-acoustic aspects) is common to a number of variants of a product, the required sample of units may be selected from the range of models offered. As a result, a number of variants may qualify for individual Telepermits based on the one series of tests.
* To be regarded as the "same electro-acoustic design", the variants of any telephony device concerned shall use the same types of transducers (microphone and receiver), the same handset geometry and construction, and the same associated transmission and signalling circuitry. For other categories of product, the same line interface circuitry should be common to all variants.
(2) This also applies where two or more versions of an equipment are marketed and the only difference is in the quantity of identical modules used.
(3) In assessing the test results the Testing Authority shall be satisfied that the same basic design is used and that all variants meet the requirements of this Specification.
(4) A separate Telepermit will usually be issued for each functionally different model so that the general conditions of the Telepermit system can be applied independent of the performance of other models. Return to Contents
2.6
Disabling of prohibited features
(1) Some devices originally manufactured for overseas applications incorporate features which are either prohibited or incompatible with the Telecom network.
(2) User Instructions for such devices shall either completely omit reference to the facilities in question or clearly explain that they are not available on products intended for connection to the Telecom network.
(3) It is strongly recommended that such features are permanently disabled. Depending on the type of product and feature concerned, Telecom reserves the right to insist on such disabling as a condition of a Telepermit grant. Disabling may be carried out in one or more of the following ways:-
(a) An internal hardware modification.
(b) Internal switching or strapping inaccessible to the normal user.
(c) Ensuring that the prohibited features can only be enabled by external programming, the information for which is not available to the user.
(4) In all cases where the disabling of a function is mandatory for the grant of a Telepermit, the following conditions shall apply:-
(a) No software-based disabling arrangements which are 'lost' when the device is unplugged from the line, disconnected from a.c. mains, or during replacement of an internal battery, shall be used.
(b) No prohibited feature shall be automatically enabled after any disruptions of the type described in (a) above.
(5) Some parameters are configurable by either the user or service personnel, and can affect compliance with PTC Specifications. The correct settings for such equipment shall be noted as part of the test results for the parameter(s) concerned and shall be included in the User Instructions.
* Parameters which are set up by DIP switches, strapping fields or non-volatile memory are applicable. Typical parameters are transmit levels, signalling options, etc.
2.7
Naive users
(1) The concept of a "naive user" was introduced by Telecom to cover any member of the general public who does not have specialised terminal equipment or knowledge.
* Reference British Standard 6789: 1987: Section 3.2.
(2) This Specification is intended to provide a degree of protection for such naive users, so that they may purchase with reasonable confidence any equipment which has been granted a "Telepermit" by Telecom.
(3) Naive users should not be misled or disadvantaged by equipment which is connected to the Telecom network by other persons. Such problems would occur in the event that inadequate operating procedures or other design deficiencies lead to users being charged for ineffective calls.
(4) Calls from ordinary customers having only telephone facilities may be inadvertently routed to automatic non-voice answering equipment. This may result in a chargeable but ineffective call.
* To minimise this problem, voice messaging back-up is recommended.
(5) The correct operation of non-voice communications requires that both calling and called parties have compatible terminal equipment. As such neither is regarded as a "naive user" for this class of call. Nevertheless, calls from customers having only telephone facilities may be inadvertently routed to automatic answering non-voice equipment or such equipment may call an ordinary customer (or naive user) in error. In such cases, it is important that such customers are not subjected to nuisance calls.
(6) Customers equipped with the necessary specialized non-voice equipment may require special protocols or procedures to guard against unauthorized access by "hackers". Any such procedures are permissible provided they do not constitute a nuisance to naive callers and they comply with the signal level and frequency requirements of this Specification. Return to Contents
2.8 Electrical safety
2.8.1
General
All equipment intended for connection to the Telecom network, including plug-in cards and modules, shall conform to the safety requirements of the joint Australian and New Zealand standard, AS/NZS 3260:1993 (or later version).
* Specification PTC 101 is currently under revision and will primarily call up AS/NZS 3260 for requirements.
* For the purposes of equipment testing, ELV is defined in AS/NZS 3260:1993 (and IEC 950:1991) as voltages below 42.4 Vac peak and 60 Vdc.
* This should not be confused with the definition of ELV applicable to electrical wiring covered by the New Zealand Electricity Regulations, where it is defined as 32 Vac rms and 115 V dc.
* A considerable proportion of telecommunications equipment available is manufactured for the North American and Japanese markets, where the mains voltage is only 100-110 V. Such overseas equipment may be compliant with the North American local requirements of IEC 950:1991, but designed with inadequate internal clearances between its components to meet New Zealand requirements, which are based on 230 V operation.
2.8.2
External power supplies
(1) Where the equipment is to be used with a separate external power supply, the combination of equipment plus power supply shall comply with the requirements of AS/NZS 3260:1993.
* Compliance testing to AS/NZS 3260, may only be undertaken by an IANZ registered laboratory, one which has been accredited by an IANZ affiliated laboratory registration authority, or one which is recognised by the Operations and Risk Management Division of the Ministry of Commerce.
(2) Where the equipment is to be used with a separate external power supply and a non-proprietary power supply is used, the operating voltage and current rating (and preferably the polarity of the connector) should be marked on the case adjacent to the socket concerned.
* This recommendation avoids the risk of an unsuitable power supply being connected via a standard or commonly used type of connector.
(3) Where a battery charger is used and this can be connected to the equipment while the equipment is simultaneously connected to the Telecom PSTN line, such chargers shall comply with the requirements of AS/NZS 3260:1993.
2.8.3
Plug-in cards or modules
(Clause deleted as requirements covered by AS/NZS 3260 referred to in clause 2.8.1 above)
2.8.4
Earth connections
(1) Where, for any reason, an earth connection is necessary for the correct operation of any equipment, the requirements of AS/NZS 3260:1993 shall be complied with.
* Suppliers should note that such telecommunications equipment is referenced to both the local earth and the remote telephone exchange earth. In the event of power faults or lightning strikes causing a rise in earth potential in the vicinity of the customer's premises, insulation breakdown is likely to result.
(2) Details of any earth connections required and the most appropriate ways of providing them shall be incorporated within the 'User Instructions' supplied with the equipment concerned.
2.9
Protection from line interference
(1) Telecom's original standard 'Master' sockets incorporated a British Telecom Type 11A gas type surge suppressor, which provided some protection against line to line transients. This was regarded as the primary protection stage for many line-powered telephones.
* Telecommunications administrations in most countries do not provide such suppression devices.
(2) As a result of extensive network changes, Telecom has reviewed its customer premises wiring practices and has introduced "2-wiring" (see Section 10). With this arrangement, the BT Type 11A suppressor will no longer be fitted to new or re-wired installations. In view of this change, customer equipment is now required to satisfy the requirements of Section 6 of AS/NZS 3260:1993 without placing any reliance on the presence of surge suppressors.
* A higher grade of surge protection will generally be installed in those areas with a known history of lightning damage or high risk of a rise in earth potential.
(3) There is no mandatory requirement for customer equipment to remain fully operational following the application of high voltages to a Telecom line, or to changes in local earth potential. The only requirements are those of AS/NZS 3260:1993.
* Any such additional protection is regarded as a marketing feature.
2.10
Temperature
All products should be compliant with this Specification at all temperatures in the range -10 degrees C to +40 degrees C.
2.11
Compliance testing
2.11.1
Test procedures
(1) The sampling evaluation and test procedures required for granting a Telepermit for any product covered by this Specification are detailed in Appendices 1 and 2.
(2) The selection of tests applicable to the stated features of the product is the responsibility of the Testing Authority. For this reason it is important that details of all available features be supplied by the applicant. If the Testing Authority is not advised of all features and additional ones are discovered after a Telepermit has been granted, then it may be necessary for the product to be retested. Where there is any doubt, the matter should be discussed with Access Standards, preferably prior to commencement of testing.
* A subsequent retest is likely to involve the applicant in greater cost than if all features were declared originally.
(3) For some complex devices the Testing Authority may have difficulties performing the necessary tests. In such cases, the Applicant shall provide the necessary liaison to ensure that the Testing Authority has sufficient information to readily perform the tests. It is recommended that specific complexities be discussed with Access Standards in the first instance, particularly if the device incorporates any process such as adaptive self-adjustment of its parameters.
* This applies particularly if the device is dependent upon host equipment for operation.
(4) The Testing Authority may be able to modify the device temporarily to meet the Telepermit requirements, but is under no obligation to do so. Full details of such modifications shall be included with the test report and furnished as part of the application.
* Such modifications are likely to increase the cost involved and the overall time taken for the testing process.
(5) Tests and measurements are to be carried out with the equipment functioning normally, and the relevant requirements of this Specification shall be complied with under normal working conditions. Where appropriate, the following shall be made available to the Test Laboratory:-
(a) Information on the most suitable means of disabling any automatic facilities
during the test programme.
* Unless suitable procedures are provided by the supplier, it may be necessary for the Testing Authority to spend additional time defining suitable test methods. Such activity will normally result in additional cost to the Applicant.
(b) Any equipment or software necessary for the initialisation of the device under test.
* Some equipment is dependent on an external device (e.g. a computer) and time can be wasted attempting to set up or initialise a device before tests can be carried out.
* Equipment that complies only under non-operational conditions is not acceptable for the grant of a Telepermit.
(6) The testing of any product shall include simple functional tests to ensure the following:-
(a) The equipment is operational to the extent that calls can be initiated,
answered and terminated reliably as appropriate to the product concerned.
(b) The equipment is operational over a typical range of line conditions.
(c) The basic functions of the equipment are demonstrated.
(7) Any functional limitations revealed by these tests shall be covered by an appropriate warning notice (see clause1.11 and Section 13) in the user instructions for the product.
* Typical examples of functional limitations are 33.6 and 56 kbit/s modems, both of which are likely to be restricted to lower bit rates when connected to some PSTN implementations. It is important that customers are aware of such limitations if the supplier is to avoid breaching the Customer Guarantees Act. Telecom gives no guarantee that such devices will operate over the PSTN at their maximum design speed (see also clause 4.9.3).
2.11.2
(2) Such Test Reports shall be in a format as close as practicable to that given in the Test Schedule shown in Appendix 3 of this Specification. All tests shall be addressed, stating "NA" where a test is not applicable.
(3) Photocopies of original Test Reports shall be accompanied by either colour photographs or colour photocopies of the product.
Test results
(1) Full test results in the form of a Test Report issued by the Testing Authority, which should include colour photographs, shall be provided in support of all Telepermit Applications.
(4) In cases where equipment has been previously tested on behalf of another Telecommunications Authority, the resultant test results may be submitted to Telecom as additional support for a Telepermit application. Such test results must be relevant to the appropriate PTC Specification requirements for them to be considered for the grant of a Telepermit. In general, Authorities' compliance certificates alone are not sufficient for acceptance.
* Test reports provided by overseas testing laboratories may provide more or less detail than is required by this Specification. Such reports are acceptable as supporting evidence, but additional tests to cover anyTelecom requirements which differ from such standards may have to be carried out.
* A composite Test Report to the required format is to be supplied, but this may be prepared from several other separate reports.
2.12
Multi-function and series connected equipment
2.12.1
Types of signal
(1) There are four main types of signal which are passed between customer equipment and the PSTN, the requirements for which are each covered separately in subsequent Sections of this Specification. These functions are summarised as follows:-
* Signalling between the PSTN and PABX's is regarded as a special case for the purposes of this clause since it is more complex than the following indicates (ref. Specifications PTC 107, 108 and 109).
(a) D.C. loop - unidirectional CPE to PSTN (ref. clause 6.4(1) and (2)).
(b) Ringing - unidirectional PSTN to CPE (ref. clause 7.7).
(c) DTMF signalling - unidirectional CPE to PSTN (ref. Section 5).
* Decadic signalling, while acceptable at present, is ignored for the purpose of this clause. This form of signalling is strongly discouraged (refclause 5.4.1(1)).
(d) Voice frequency transmission - primarily bi-directional between CPE and
PSTN (ref. Section 4, and also clause 11. 4).
* clause 11. 4. describes requirements for caller identification which is a unidirectional (PSTN to CPE) function. However, caller ID uses the on-hook data facility which has bi-directional capability and is described in Technical Document TNA 102, Section 10.
(2) There are three basic functional categories of equipment described in the following clauses. These categories are dependent on various combinations of the above signalling functions and how they are used. Some equipment will fall into more than one category, and may change categories for some of the above functions at different stages of a call.
(3) All of the functional categories available on equipment shall be fully tested.
* See also clause 2.4(5)). which calls for list of functions as a mandatory requirement for all Telepermit applications. Return to Contents
2.12.2
Terminating function
Devices with a terminating function are characterised by the application of a d.c. loop and transmission termination, either in response to incoming ringing or for the purpose of initiating a call.
Return to Contents
2.12.3
Bridging function
(1) A bridging function involves no application of a d.c. loop signal and generally performs a monitoring role only. With the exception of devices designed specifically to monitor ringing or on-hook data signals, bridging equipment relies on other separate terminating devices to provide the d.c. loop.
(2) All customer equipment effectively performs a bridging function when in the on-hook (idle) state, and shall be tested as such. The requirements are detailed as 'on-hook requirements' in subsequent Sections of this Specification.
2.12.4
Series connected devices
(1) Series connected devices (interposed between the PSTN line and another CPE item) can operate under two separate functional modes as follows:-
(a) Terminating.
(b) Non-terminating.
(2) Terminating devices Series connected equipment which has only a terminating function is characterised by the following:-
(a) The line port terminates the PSTN line.
(b) The terminal equipment port presents a 'network-like' interface to the terminal device.
(c) Signals are received on one port and similar signals (not necessarily identical) are reproduced on the other port (bi-directional).
* A common example of terminating series connected equipment is a PABX.
(3) Non-terminating devices Series connected equipment which has only a non-terminating function is characterised by the following:-
(a) The line port does not terminate the PSTN line, but instead passes all signals directly between the two ports.
(b) The d.c. loop required for terminating or initiating a call is usually provided by separate equipment connected to the terminal equipment port.
(c) There is likely to be series and shunt impedances within non-terminating devices as shown in Fig. 2-1(b).
* A typical example of a non-terminating series connected device is call monitoring equipment.
FIG. 2-1(a) SERIES CONNECTED DEVICE - TERMINATING MODE
FIG. 2-1(b) SERIES CONNECTED DEVICE - NON-TERMINATING MODE
(4) Multi-function devices
Use of the signal functions described in clause 2.12.1 varies on certain types of series connected devices. Such equipment may operate as a terminating device for some functions and a non-terminating device for others, or they may vary for different stages of a call. For this reason, the terms 'terminating' and 'non-terminating' shall, for the purposes of this Specification, be regarded primarily as function descriptions rather than equipment descriptions.
* An example of a multifunction device is a fax machine which responds to distinctive alert signals (i.e. Telecom's "Faxability" service).
