Technical Guidance Note 25

TOPIC: EPROM emulators and similar test equipment

ISSUE: 2

REVISION DATE: 27.1.98

PREVIOUS REVISION DATE: 6.9.95

BACKGROUND: EPROM emulators and similar test equipment (e.g. ATE) are connected to exposed unscreened circuit boards. Emissions from the boards could negate any reliable assessment of the test equipment's EMC characteristics.

PROBLEM: How should this class of equipment be tested?

GUIDELINES: The supplier can demonstrate compliance using either the standards or the TCF route.

EPROM emulators can be regarded as test equipment and as such come within the scope of Regulation 9 of the UK EMC Regulations. Regulation 9(1) (a) modifies the protection requirements for emissions by introducing the concept of an "immediate electromagnetic environment". The apparatus (e.g. EPROM Emulator) must not prevent other apparatus situated outside the immediate electromagnetic environment from operating as intended. This allows the manufacturer to define a safe protection distance. Since the EPROM Emulator is likely to generate a high level of electromagnetic emissions, the manufacturer should carry out some measurements to determine the distance from the device at which the emissions are below an acceptable level (e.g. below the EN55022 Class A limit for IT equipment). The Competent Body would ensure that the protection distance was stated in the user manual with clear instructions that apparatus likely to be sensitive to electromagnetic emissions (e.g. radio equipment) should not be operated within the stated protection distance from the EPROM Emulator.

Disclaimer
No responsibility or liability can be accepted by the EMC Test Laboratories Association or any of its officers or members for the contents, specifications and/or advice referred to or contained in this Technical Memorandum and/or action taken as a result of information contained in this Technical Memorandum. Note that:
1. The Association is not by supplying this Technical Memorandum providing professional advice or guidance to any specific party on any specific matter and no legal relationship is created by the provision of this Technical Memorandum.
2. Parties should take specific advice when dealing with specific situations and consult their own professional advisors in this regard.
3. Members are free to deviate from the above guidelines where they think it appropriate, unworkable, or not commercially viable. Under these circumstances, the EMCTLA Secretariat should be informed of the reasons for the deviation so that the matter can be reviewed.