I decided to create an article with an easy-to-read and understand list of the most basic ABYC Marine Safety Standards that everyone should know and follow. My goal is to update this article once a week with a new standard. So please check back weekly!
Supporting of the conductor shall occur every 18inches. You could certainly provide support well before the 18inch mark if you would like. There are various ways to provide support for the conductor; Insulated metallic clamps, plastic clamps, screw mount zip ties, wire trays, and zip ties with mounts.
I mainly use insulated metallic clamps and screw-mount zip ties. I am a big fan of the insulated metallic clamps. ABYC also specifies the use of metallic clamps for all conductors routed near machinery, engines, and moving shafts. If you are using metallic clamps and not insulated metallic clamps, you must provide chafe protection for the conductor at the location of the metallic clamp. To keep it easy, I only use insulated metallic clamps from Ancor.
Here is the exact ABYC Marine Safety Standard regarding wire support:
184.108.40.206.9 Conductors shall be supported throughout their length or shall be secured at least every 18 in (455 mm) by one of the following methods:
220.127.116.11.9.1 by means of nonmetallic clamps sized to hold the conductors firmly in place. Nonmetallic straps or clamps shall not be used over engine(s), moving shafts, other machinery, or passageways, if failure would result in a hazardous condition. The material shall be resistant to oil, gasoline (petrol), and water and shall not break or crack within a temperature range of -40-185°F (-40-85°C);
18.104.22.168.9.2 by means of metal straps or clamps with smooth, rounded edges to hold the conductors firmly in place without damage to the conductors or insulation. That section of the conductor or cable directly under the strap or clamp shall be protected by means of a loom, tape, or another suitable wrapping to prevent injury to the conductor; or
22.214.171.124.9.3 by means of metal clamps lined with an insulating material resistant to the effects of oil, gasoline(petrol), and water.
EXCEPTIONS to E-126.96.36.199.9 through E-188.8.131.52.9.3:
1. Battery cables within 36 in (914 mm) of a battery terminal.
2. Cables attached to outboard engines for the length required for normal engine operation.
3. Final termination for battery cables to the outboard or inboard engine connection can be up to 24 in (600 mm) if contained in a sheath for this distance.
TERMINAL POST CONNECTIONS
I see this standard betrayed often. Especially on the battery terminal posts. It’s an easy standard to follow once you are aware of it.
You can attach a maximum of FOUR terminals to any one terminal stud. I strive for one terminal per post, but sometimes that is just not feasible. And that’s ok, as ABYC gives you the grace of allowing up to four.
Once you start stacking terminals on a single terminal post, you must start with the highest current draw conductor at the base of the terminal post. Then the next highest current draw conductor goes on, followed by the next highest, and so on. View it as building a pyramid.
Another important factor to remember is you must use the right size terminal for that specific terminal post. If the terminal post is 5/16th, use a 5/16th terminal. Your terminal can’t be bigger i.e.- 3/8th. You need your terminal to fit correctly and allow the most surface-to-surface contact between the terminal and the terminal post.
Even though you are allowed to have up to four terminals on a single terminal post, doesn’t mean you should, or that it can safely be done. Sometimes it can’t. Especially if the terminal post is a smaller size. You must make sure your lock washer and nut (or nylock nut) can be fastened down correctly and to spec.
A great way to conquer this standard is the use of terminal blocks and busbars. If multiple terminals go to a single terminal post, you can simply install a multi-post busbar. You install all the terminals onto the busbar and then have just one cable going from the busbar to that single terminal post.
Here is the exact ABYC Marine Safety Standard regarding Terminal Post Connections:
184.108.40.206.11 No more than four terminals shall be secured to any one terminal stud. If additional connections are necessary, two or more terminal studs shall be connected using jumpers or copper straps.
220.127.116.11.11.1 Multiple conductors connected to a terminal stud shall be installed with the highest ampacity conductor terminal closest to the base, followed by successively smaller ampacity conductor terminals.
18.104.22.168.12 Ring and captive spade-type terminal connectors shall be the same nominal size as the stud.