Hi Amund:
I suggest you and your client and the regulatory
authority meet to address the situation.
Here are the issues as I understand them from your
message:
1. In idle mode, the emissions are comfortably
below the maximum allowed emissions.
2. In transmit mode, the emissions exceed the
maximum allowed emissions. The duration of
the transmission is 25 ms. The repetition
rate of the transmission is about 1/hour.
3. The emission level is probably related to the
nature of the system, i.e., transmission via
the power distribution network.
I feel that 25 ms/hour is the important parameter.
I suspect that most motor-starting events exceed
the emission level, and for more than 25 ms. Like-
wise, I suspect most igniter events also exceed the
emission level and for more than 25 ms. Does
your regulatory authority permit such emissions?
Set up the system for normal operation. Ask the
regulatory authority to measure the emissions. The
emissions will be in compliance for 1 hour. The
regulatory authority must be observing the emissions
at the moment of the 25 ms transmission in order to
determine if the emissions exceed the allowed level.
I suspect this is a difficult measurement. The
receiver or SA must be tuned to the transmit
frequency during the 25 ms transmit interval. This
probably requires advance knowledge of the transmit
frequency, and therefore the measurment is not an
agnostic measurement. (If you were submitting the
equipment to the regulatory authority, do you have
an obligation to inform them of expected performance
of the unit, especially the specifics of the transmit
mode?) And, there must be some means of capturing
the data during the event. Short of staring at the
SA screen for an hour or more, I'm not sure this can
be done except with exceptional effort and additional
equipment.
The preceding paragraph is something of a game to
play with the regulatory authority.
> So, why should the company close down ? Because if the national authority
> gets what they want, there will be one sale. Logical, but is it a correct
> prohibition the authority call?
The company SHOULD have known that its product would
exceed conducted emissions. The company SHOULD have
taken appropriate steps with the regulatory authority
to know whether or not its product would be approved
BEFORE it invested in the product development.
This is not a fault of the regulatory authority, but
a fault of the company to not understand the
regulations BEFORE it developed the product.
Best regards,
Rich
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