@Ken Cross is correct, leaving the AC Hot connections exposed is an issue. Back in day, a piece of split loom wire insulation was placed over the copper bus bar to protect it. Better than nothing, not as good as a well covered panel. So far, the split loom has protected my AC panel for about 26 years.
AC panel wiring
- Thread starter GABristol29
- Start date
When installing my new AC panel I decided to add another breaker. To do so I had to loosen the screws of all the breakers where they connected to the busbar, to move it a bit to get the new breaker in.
While tightening all the screws I was distracted by a phone call. Finished the call and finished the install.
Since I didn't have my clear cover ready to install I used split loom to cover the "hot" busbar connecting the breakers.
I left the distribution panel open while working on some other things. Glad I did. I smelled something hot and found the split loom was melting.
Turned out I missed tightening a screw on one of the breakers. The resistance of the loose screw at the busbar/breaker connection heated the busbar hot enough to melt the split loom.
It showed me how important good connections were to avoid high resistance and the heat a high resistance connection can produce.
While tightening all the screws I was distracted by a phone call. Finished the call and finished the install.
Since I didn't have my clear cover ready to install I used split loom to cover the "hot" busbar connecting the breakers.
I left the distribution panel open while working on some other things. Glad I did. I smelled something hot and found the split loom was melting.
Turned out I missed tightening a screw on one of the breakers. The resistance of the loose screw at the busbar/breaker connection heated the busbar hot enough to melt the split loom.
It showed me how important good connections were to avoid high resistance and the heat a high resistance connection can produce.
@Ward H what's expression about experience is what you got by not having it when you need it?
This year I added an ELCI to my AC Panel. It required cutting a little off the copper bus. Got everything buttoned up, double checked all the screws, plugged it in and got a lot pop and some smoke. Double checked everything again, plugged it in, got the same results. Spent some money and bought a new main breaker, screwed everything tight, double checked, plugged it in, smoke and noise again. Eventually I found that I had not cut the bus at a precise right angle and a little tiny corner was just nanometers away from the neutral breaker. Just close enough to spark, smoke and trip the breaker.
AC wiring on a boat can get tricky - much worse than a house as you have multiple sources of AC aboard. Study the ABYC specs to the point you understand them.
I did some rewiring on a Bristol 38 trawler some years ago. The shore power breaker/polarity protection can only be so far from the shore power inlet - I had to add a separate panel closer to the inlet. Keep track of the different AC sources (shore, inverter, generator) and make sure the things that can run from each source are appropriate. ie: don't run the battery charger off the inverter, and probably not the electric stove.
Do not assume that what's installed is correct. This Bristol had 3 bilge pumps installed, nicely staged in size and depth of activation. Small guy (pint size) in the bottom of the bilge, quart size pump a bit higher, then the big gallon size pump. All run off the same breaker which wasn't sized to handle all 3 pumps!
I did some rewiring on a Bristol 38 trawler some years ago. The shore power breaker/polarity protection can only be so far from the shore power inlet - I had to add a separate panel closer to the inlet. Keep track of the different AC sources (shore, inverter, generator) and make sure the things that can run from each source are appropriate. ie: don't run the battery charger off the inverter, and probably not the electric stove.
Do not assume that what's installed is correct. This Bristol had 3 bilge pumps installed, nicely staged in size and depth of activation. Small guy (pint size) in the bottom of the bilge, quart size pump a bit higher, then the big gallon size pump. All run off the same breaker which wasn't sized to handle all 3 pumps!
No, the bilge pumps were all 12V DC. My point is that there's no assurance that the wiring in a boat was ever correct - even when the boat was new. The electric range on this trawler had a very clean oven - because the range was wired incorrectly and the oven (and one top burner) weren't ever connected!
And where would one obtain those specs? Are you saying you purchased them? Example:
ABYC E-11-2018
AC & DC ELECTRICAL SYSTEMS ON BOATS
This standard is a guide for the design, construction, and installation of alternating current (AC) electrical systems and direct current (DC) electrical systems on boats.
$130.00
That's $130 for the pdf.
Here's one source of good info although not the latest spec.
http://www.moyermarineforum.com/forums/showthread.php?t=9278
http://www.moyermarineforum.com/forums/showthread.php?t=9278
I was reacting to the occasional occurrence of someone glibly advising another to "read the ABYC Standards" when they are, in fact, not intended for the general public, and fairly expensive to acquire.
Interesting that the guy posted those 2008 documents stating that they "are available as open source because the copyrights have expired." Nothing could be farther from the truth. He neither understands open source (as compared to public domain) nor copyright law.
Interesting that the guy posted those 2008 documents stating that they "are available as open source because the copyrights have expired." Nothing could be farther from the truth. He neither understands open source (as compared to public domain) nor copyright law.
The whole ABYC standards book is expensive, however, with a little effort it is possible to find excerpts from reliable sources. For example, here's one from Peter Kennedy: https://shop.pkys.com/ABYC-standard-for-installation-and-wiring-_b_9.html
Books like Charlie Wing's book reproduce the charts from ABYC standards and explain them in plain language.
Noted experts, like Steve D'Anotonio will explain or list ABYC standards in their writing.
Here's a link to the electrical standards that apply to all boats built after July 31, 2009. https://www.paneltronics.com/atimo_s/news/E11Excerpts.pdf
Granted there are revisions to the standards each year, but these sources will get you on the right track.
Books like Charlie Wing's book reproduce the charts from ABYC standards and explain them in plain language.
Noted experts, like Steve D'Anotonio will explain or list ABYC standards in their writing.
Here's a link to the electrical standards that apply to all boats built after July 31, 2009. https://www.paneltronics.com/atimo_s/news/E11Excerpts.pdf
Granted there are revisions to the standards each year, but these sources will get you on the right track.