Products > Test Equipment
EMC conducted emissions pre-compliance testing with home-made LISN
Jay_Diddy_B:
Hi,
I am not sure where your phase limits are coming from. If I analysis the circuit in LTspice:
LTspice gives a phase angle of 84.7o which is pretty close to the 84.18o that you measured.
There is really good correlation between the response predicted by LTspice and the measurements that you made. This indicates that the circuit is 'free' from parasitic components.
Regards,
Jay_Diddy_B
EMC:
Phase is from the CISPR LISN Spec. I have seen several LISNs and all are high at 150kHz; I don't know how to lower it.
Jay_Diddy_B:
Hi,
This circuit matches the impedance curve:
These are the results:
This was achieved by placing a 1 Ohm resistor in the circuit.
The problem is, I can't find a 5uH LISN schematic with the resistor in it.
Regards,
Jay_Diddy_B
T3sl4co1l:
Hmm, an FCC Part 15 LISN defines a 5 ohm resistor in series with the bulk capacitor towards the mains side. Which seems reasonable to me as setting the low frequency line impedance and damping characteristics.
Tim
EMC:
So they must be providing for the resistance of the inductor. I guess the easiest solution would be to just live with it.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version