| Author |
Message |
david&leigh (209.223.227.171)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 18, 2001 - 12:09 am: | |
I have a 2"x15"x1/4" copper strap that I will bond to the bus frame and wire all my house DC negatives to. I would like to bond a buss bar to this strap similar to a neutral buss in an AC breaker panel. It has about 40 holes with screws in which to secure all the wires. I cannot find anything in the NEC that dissallows this. Is this method acceptable? It sure would save a lot of drilling into that copper bar. Thanks, David Anderson |
Jim Stacy (12.87.108.213)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 19, 2001 - 12:39 am: | |
It'l be fine. Just be sure it does not actually connect to the AC neutral, just to AC ground.
Jim Stacy |
Dave (64.111.120.146)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 20, 2001 - 2:02 am: | |
NEC prohibits grounding a second ground bar to the neutral wire of primary box and the second box. The second panel box floats from neitral so to speak to prevent ground loops. Check with an electrician friend. |
JJ (209.26.126.28)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 20, 2001 - 1:29 pm: | |
Dave's right, but do try to sepatate the AC/DC systems. Running a ground wire from all DC appliances is a good idea rather than using the body for a ground return. This will stop high capicitance loops, and problems with AC/DC low voltage systems such as computers. Billy- if you read this my computer is still down, (I'm using a comuter at the public library in Ft. Myers) call me at 941 656 4284 or wait patiently 'til I get back online. Cheers...JJ |
Clarke (216.17.134.204)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 25, 2001 - 10:52 pm: | |
You should be able to get a bus bar from any well-stocked electrical supplies distributor or electrical contractor. Screw it securely to your copper bar, then run the ground wires of your DC components and loads to the bar. If you get into serious current, several bus bars might be appropriate.
As for the comments about AC power separate from DC, just remember:
1. In the first breaker or fuse panel from the main meter on a shore-power system, the neutral bus is bonded to the panel enclosure which is always connected to the safety ground bus.
2. Any fuse or breaker panels beyond that first panel must keep the AC neutral electrically isolated from the panel enclosure which must be connected to a separate safety ground wire returning to the safety-ground bus in the main panel upstream. This is NOT to prevent ground loops as erroneously stated by Dave. It is to provide a reliable ground path from the panel housing and anything connected to the safety ground lines going out to receptacles, tool power cords, etc., thus protecting humans in case a neutral wire were to break or open up for some reason. NEUTRAL-WIRE CURRENTS MUST NEVER PASS THROUGH A SAFETY-GROUND WIRE UNDER ANY CONDITIONS. That is why they are not bonded together in subsequent fuse or breaker panels, and that is why 240-volt shore power MUST ALWAYS BE CONNECTED USING 4-WIRE CABLES AND CONNECTIONS.
3. When connected to shore power, the safety-ground wire in the shore-power cord must connect to the bus frame. It would be well if it were connected to your bus bar as well, provided there is no possibility that the connection between the bus frame and your copper bus (no pun intended) bar can be compromised; i.e., it must be securely grounded to the frame using methods that will not allow the ground connection to deteriorate due to rust, corrosion, or other factors.
4. It would be wise to return the negative wiring from 12- or 24-volt DC circuits, including headlights, marker lights, etc. to the copper bus, then connect it to the negative terminal of your battery bank. If you have separate house and starter/bus-run batteries, tie their negative terminals to a common bus bar that provides the common overall bus ground point.
This doesn't solve every problem (such as electrical noise due to static discharges, etc., but you'll have a pretty stable system if you follow these general guidelines.
Clarke |
Jim Ashworth (Jimnh) (172.149.90.227)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 26, 2001 - 8:26 pm: | |
Clarke- Check the NEC for ground loops. Dave is correct. This is to prevent multiple grounds having different potentials. It is well diagrammed in the NEC Handbook.
Jim |
Steve Fessenden (63.27.88.15)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 27, 2001 - 12:06 am: | |
I hate to add anything to all this high powered and accurate information,but, for DC, couldn't you also run a single uninterupted heavy copper wire, such as a #2 or larger welding wire as a bonding wire looping everywhere you need a ground? That would also give you a way to bond the frames of any device that might otherwise be sitting at a different potential. Like a boat.
Steve Fessenden |
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