We manufacture a Network Terminating Unit (NTU) for data transmission over 
a copper pair to a similar NTU.  The TNV circuit is isolated from the SELV 
circuit of the NTU which is unearthed.  This may however be earthed via a 
DTE connected to the data port of the NTU.  The NTU is powered via a 
connector from an external 12V a.c. powerpack (line frequency transformer), 
which provides an unearthed SELV output.  The powerpack we would normally 
purchase from a supplier.  Purchasers of the NTU may either be carriers who 
would use it to provide data services or individuals who may use the NTU 
over leased lines.

The NTU is to be safety tested to EN60950 by us, and powerpack separately 
by the powerpack manufacturer, also to EN60950.  We then intend to test the 
NTU complete with the powerpack to EN55022. 

Preferably using the self-certification procedure we wish to CE mark and 
sell the NTU, with or without powerpack, in several countries in the EEA. 

Several questions arise:

1(a)  Given that no Common Technical Requirements (CTRs) presently apply to 
the NTU which transmits up to 128 kbps via proprietary methods.  Does the 
Telecommunications Terminal Equipment (TTE) Directive 91/263/EEC apply? 
i.e. is  the NTU "telecommunications terminal equipment"?

1(b)  This appears to depend on whether the NTU is considered to be part of 
the network or connected to it.  Is it therefore application dependent?

1(c)  If so, does the TTE Directive apply to the NTU with powerpack, or 
just the NTU.

1(d)  Is this decided on a per-country or EEA-wide basis? 

2(a)  Can a CE marked powerpack be sold as an individual unit in the EEA?

2(b)  Can the NTU be CE marked and sold in the EEA without a powerpack, but 
specified to be used with any appropriately rated CE marked powerpack?

2(c)  Would the following be a suitable basis of justification for a TCF?
The NTU would satisfy the LV and EMC directives.  Further, the conducted 
emissions from the NTU are well below the specified limits and are little 
influenced by the powerpack.
The specification of any powerpack used would require:
To be CE marked regarding the LV and EMC directives.
The powerpack would meet defined electrical performance characteristics and 
meet any requirements for which the safety approval of the NTU is 
dependent.  
e.g. EN60950 para 2.11, Limited Power Source.

2(d)  If the NTU is CE marked and sold separately from the powerpack, what 
approval process is then required for the powerpack concerning the TTE 
directive or per-country telecomms?

3(a)  If we sell the NTU with a purchased CE marked powerpack as a unit.  
Are we protected by the powerpack manufacturers Declaration of Conformance, 
or are we also liable for powerpack conformance.

3(b)  If we do this, must the manufacturing quality procedures for the 
powerpack manufacturer appear in our TCF?

4.   Who in the EEA is authorised by the authorities to provide advice on 
the above questions, from whom we can determine a reasonable basis to 
proceed with confidence that we have satisfied the requirements?


Rod Mason
-------------------
Principal Engineer
Datacraft Technologies Pty Ltd
252 Maroondah Highway, Mooroolbark
(PO Box 383, Mooroolbark, 3138)
Victoria,  AUSTRALIA  
Tel: +61 3 9727 9261 (GMT + 10 Hrs)
Fax: +61 3 97279 4021
E-Mail: [email protected]

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