Did you ground your PD 9200 series converter?
I recently installed a new PD9260C deck mount converter in my fifth wheel. It did not come with anything resembling installation instructions, but it did have this schematic: The converter A...
Forum Discussion
wgriswold wrote:kellertx5er wrote:wgriswold wrote:
OK, I am going to display my ignorance, but here goes.
Is the AC ground to earth connected to the frame? I think so but am not sure.
My understanding is that the AC ground to earth is connected to the case of the convertor via the plug. So it seems that there would be no need for an additional ground to earth via the frame.
Why is the DC negative wire also wired to the frame which is also part of the negative circuit of the 12V system?
Maybe it is important to connect the negative component of the DC system to the earth ground of the AC system?
Thanks for helping me understand this.
As stated previously in this thread, NEC Art. 551.20(C) requires the enclosure of a converter to be connected to the vehicle frame with a minimum #8 copper conductor. Period, end of issue.
Yes, I read the thread. I am wondering why this is required. Of course, I would follow requirements of code, but I wanted to understand why.
Thanks for all the answers. I still don't understand why two grounds are necessary in the AC side and two paths to negative side of battery are required in the DC side.
AC safety ground and DC ground (negative) are both tied to the frame of the RV.
I think the idea is that if the normal current carrying negative wire to the battery were to fail somehow, you would potentially have the entire DC current flowing through the safety ground on the AC side if the converter were not separately bonded to the vehicle frame. The safety ground is only sized to carry the fault current of the AC input, which would be limited to 15 or 20 A for a normal plug. Since the converter can put out several times that current, that would be a significant overload of the safety ground wire and could very well start a fire.
If the DC output of the converter were isolated (in the converter) from the frame or ground, presumably the extra bond would not be required for safety, though the code may not make such a distinction. If nothing else, such isolation could also break down without it being evident so long as the normal negative DC connection is unimpaired.
