Gary, yes, that is correct. My point is that the carrier level is 3 V/m, modulated or not. The modulation adds peak levels which are not there in an unmodulated carrier. There are people around who want the 3 V/m to be peak, because their devices fail if the modulated carrier level is not reduced to keep the peak of the modulation cycle at 3 V/m. However, that is not what was intended in the IEC/EN standard. When a 3 V/m carrier is modulated 80 %, the peak level of the modulated signal is 1.8 x 3 V/m = 5.4 V/m; but the minimum level is 0.2 x 3 V/m = 0.6 V/m; and the carrier level remains 3 V/m. Regards, EdB
-----Original Message----- From: Gary McInturff [mailto:[email protected]] Sent: Wednesday, September 06, 2000 4:47 PM To: Bronaugh, Edwin; ''[email protected]' ' Subject: RE: Immunity Testing to EN55024 Are you sure you are reading that correctly. In the radiated portion in a note to the side of the levels it says that the test level is prior to modulation. I believe that is trying to say turn up the levels until 3 v/m measured and once that is done then begin the modulation and start sweeping through the test frequencies. gary -----Original Message----- From: Bronaugh, Edwin To: '[email protected]' Sent: 9/6/00 11:31 AM Subject: RE: Immunity Testing to EN55024 It remains 3 V/m. However, the peak envelop power is 5.1 dB higher than the unmodulated carrier level. If you set a signal generator to produce an unmodulated carrier (usually through an amplifier) of 3 V/m and then modulate it 80 %, the generator will still show the same carrier level, but the amplifier will have to produce nearly four times as much power. If you measure the E-Field level with an average (carrier) detector in an EMI meter, the carrier level will not change from unmodulated to modulated. If you use a peak detector, the E-Field level will be 5.1 dB higher. EdB -----Original Message----- From: Antonio Cinquino [mailto:[email protected]] Sent: Wednesday, September 06, 2000 10:34 AM To: '[email protected]' Subject: Immunity Testing to EN55024 Hello Group, Table 1 of EN55024 calls for a test specification of 3 V/m (umodulated, r.m.s) radio-frequecny EM field for Immunity at the enclosure port. Does anyone know off-hand the value when the signal is 80% modulated with an AM signal of 1kHz as called for in the same table? Antonio Cinquino CAE Electronics Ltd. Electrical System Designer Phone : (514) 341-2000 (ext. 4303) Fax : (514) 340-5552 Email : [email protected] <mailto:[email protected]> ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
