Dear all, I have a product which is intended to be connected on the mains (230V AC) or on the electrical system of a locomotion engine (12 to 24VDC). This product is provided with two power cords : one standard 2 poles cord for the 230V and the second one for connection to the DC power supply. Both are permanently connected to the product. This means that when your are connected to the 230V, the DC power cord plug could be accessible, and when you are connected to the DC power supply, the 230V inlet could be accessible. (both can be connected simultaneously, and in this case, the AC power supply is automatically selected).
My main concern with this product is regarding the insulation system when the DC cord is connected to DC power supply, with the 230V inlet accessible. The DC input is connected to an internal DC/DC converter with 300VDC output. This output is connected directly just after the rectifier bridge of the product power supply. The 300VDC is regarding as a floating output. In this situation, the only one insulation between the 300VDC and the 230V inlet is the RECTIFIER BRIDGE. In normal use, the diodes act as a barrier. If one diode breaks (first default condition) one of the 300VDC pole is present on the 230V inlet. This 300V being floating, there is no hazard. However, can we suppose that the diode is appropriate to insure a good insulation in normal use ? What is your meaning on this problem ? Have you encountered this kind of problem, and how did you solve it ? In advance, I thank you a lot for your answers, Best regards ================================================================ Pierre Selva Laboratory responsible EMC and Safety laboratory SMEE Actions Mesures Ph : 33 4 76 65 76 50 ZI des Blanchisseries Fx : 33 4 76 66 18 30 38500 VOIRON - France e-mail : [email protected] ================================================================ --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
