We have a 1976 Hunter 30, which will we are going to start putting back together pretty soon (weather permitting), The whole electrical system is going to be replaced, and I have been (kind of) plodding through the way the old one was put in. It seems like most of the gound(s) ultimately wind up at the motor. The questions I still have is 1) is there some internal (in hull) ground from the keel to the motor (or should there be), 2)is there some internal ground from the mast to the motor (or should there be). I am not sure if there are any zinc's on the hull, I just havent looked, and I am not sure if there is supposed to be. I know there are two on the shaft, and the new motor has zinc's. Do I need to put additonal one anywhere else?. I haven't gone so far as to use a multi-meter yet. I have a new Blue Sea Systems 8084 (Ac-DC) panel, and all of the circuits (Both AC & DC) have positive lugs,negative lugs, and common ground (via a bus bar). The DC grounds are all interconnected, the AC grounds all go to the shore power ground (through a BUS bar). Any help (in laymans terms) would be greatly appreciated. I am not going to use any bus bars, I intend to run all new wire from the panel to each and every appliance, outlet, or demand, no breaks, no splices. I personally dont have much faith in crimping connections, so I intend to solder all the connections to lugs, terminals or connectors, and heat shrink them with adhesive heat shrink. Any insight or experience would be greatly apreciated.
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electrical grounding vs lightning vs SSB/Ham radio
The engine grounds to the water via the drive shaft. Don't forget to install a sacrificial zinc on the shaft and check it periodically once the boat is in the water - here in Florida the boats get cleaned monthly and the zincs get checked at the same time. You are in colder water, so I am not sure if the boats get cleaned as often. Some people put in a lightning arrestor ground and connect the mast to the keel. I think a better bet is to ground the shrouds to the water temporarily via a good cable and chain when a storm threatens or away from the boat. Don't connect any lighting ground to the DC ground. Ground your DC system to the engine block - there should be a bolt with a connection already in place. Be suspicious of old cables. Mine was causing a grounding problem until I replaced them all. Bigger is better Don't connect the AC ground to the DC ground this can cause problems. Don't connect the AC ground to engine block. If you bond the thru-hulls, don't connect them to your DC gound. The one to worry about is Air Conditioning water intake because the flow of salt water can cause problems (if you have AC in MA). Similarly for the frig if water cooled. A friend tied his bonding system to the engine block and had many problems. Only bother bonding them together if you can get a zinc in there somewhere. If you are in a marina that has electrical problems find some way to connect the bonding system (thru-hulls) to a zinc, even if it is just a fish zinc. If you have an SSB/Ham Radio, then you may want to ground that to the lead keel. To connect electircally to the keel, drill and tap the top of one of the keel bolts (just enough to connect a wire connection. If you attach a lightning system to the keel, drill and tap the top of a keel bolt, drill and tap the mast, and connect the 2 with a flat piece of copper not a copper pipe - avoid right angles! I have been told this risks losing the keel, but if the mast is struck, it is a good bet that the lighting will exit via the keel anyway if there isn't another choice.
The engine grounds to the water via the drive shaft. Don't forget to install a sacrificial zinc on the shaft and check it periodically once the boat is in the water - here in Florida the boats get cleaned monthly and the zincs get checked at the same time. You are in colder water, so I am not sure if the boats get cleaned as often. Some people put in a lightning arrestor ground and connect the mast to the keel. I think a better bet is to ground the shrouds to the water temporarily via a good cable and chain when a storm threatens or away from the boat. Don't connect any lighting ground to the DC ground. Ground your DC system to the engine block - there should be a bolt with a connection already in place. Be suspicious of old cables. Mine was causing a grounding problem until I replaced them all. Bigger is better Don't connect the AC ground to the DC ground this can cause problems. Don't connect the AC ground to engine block. If you bond the thru-hulls, don't connect them to your DC gound. The one to worry about is Air Conditioning water intake because the flow of salt water can cause problems (if you have AC in MA). Similarly for the frig if water cooled. A friend tied his bonding system to the engine block and had many problems. Only bother bonding them together if you can get a zinc in there somewhere. If you are in a marina that has electrical problems find some way to connect the bonding system (thru-hulls) to a zinc, even if it is just a fish zinc. If you have an SSB/Ham Radio, then you may want to ground that to the lead keel. To connect electircally to the keel, drill and tap the top of one of the keel bolts (just enough to connect a wire connection. If you attach a lightning system to the keel, drill and tap the top of a keel bolt, drill and tap the mast, and connect the 2 with a flat piece of copper not a copper pipe - avoid right angles! I have been told this risks losing the keel, but if the mast is struck, it is a good bet that the lighting will exit via the keel anyway if there isn't another choice.
Soldering connections
Solder is a wonderful electrical connection, but it is a horrible mechanical connection. Crimping works good when done right. If you have the time, you can buy crimp connectors (ring connectors and fork connectors) that can be both crimped and solderd. Do NOT solder wires directly to anything. Only solder the a connector and attach to the panel and whatever via connectors. Bus bars are good for things like DC ground, and where you have one circuit breaker for several things (e.g. cabin lights). Connect 1 wire from the breaker to the bus, then connect the various runs from the various lights to the bus. If you try to connect to many things directly to the breaker you end up with a rats nest of wire behind the panel. Keep the buses covered after installation even if just with tape. Bus bars or junctions can also work well with things that are supplied with wires already in place that need to be connected to the rest of the system. Take a look at a Rule bilge pump. It is supplied with wires already in place so connecting the DC hot and the manual switch needs to be done connecting wire-to-wire via some connector. This also makes replacement easy. (add connectors to the ends of the wires on the new pump and you are ready to go using the existing juction.)
Solder is a wonderful electrical connection, but it is a horrible mechanical connection. Crimping works good when done right. If you have the time, you can buy crimp connectors (ring connectors and fork connectors) that can be both crimped and solderd. Do NOT solder wires directly to anything. Only solder the a connector and attach to the panel and whatever via connectors. Bus bars are good for things like DC ground, and where you have one circuit breaker for several things (e.g. cabin lights). Connect 1 wire from the breaker to the bus, then connect the various runs from the various lights to the bus. If you try to connect to many things directly to the breaker you end up with a rats nest of wire behind the panel. Keep the buses covered after installation even if just with tape. Bus bars or junctions can also work well with things that are supplied with wires already in place that need to be connected to the rest of the system. Take a look at a Rule bilge pump. It is supplied with wires already in place so connecting the DC hot and the manual switch needs to be done connecting wire-to-wire via some connector. This also makes replacement easy. (add connectors to the ends of the wires on the new pump and you are ready to go using the existing juction.)
P
Patrick
Do it right
Better read up on this subject before you start this job if you haven't. It is one of those things which is more important than it might seem. As I understand it, bonding refers to the boats mechanical parts (rigging) and how they are electrically connected to each other (or not). There are different schools of thought on this subject. I would advise using the original plan as the boat was built. Grounding is an electrical term which is used in rather imprecise ways. Do not confuse the two. The main problem arises from very small DC voltage differences between these systems and the ensuing electrolytic corrosion. There can also be problems from dissimilar metals used for wiring connections. Generally, keep the DC ground separated from the AC ground and seperated from the "AC return". Do not connect the bonding system directly to the ground system(s). Improper grounding affects not only your own boat but your neignbors boat as well. The reverse is also true. The RF (radio) ground can be isolated from any DC component by using a capacitance isolation system. The coaxial cables shield is supposed to be an RF ground and sometimes causes problems if someone intentionally or inadvertantly connects it to the bonding system. Debra, I respectfully disagree about your assesment of soldered connections. Done properly with the proper amount of heat, correct (preferably eutectic) solder, and the right flux, it is probably the best wiring technique I know of. Use care not to allow solder to flow into the areas which are subject to mechanical flexing and it is far superior to any crimped connection I have ever seen. Either method works but both require the proper tools, technique, and attention to detail. Workmanship I have seen on boats is usually very poor and wiring is not labeled or routed with much if any attention or care. Do it right and it will save a lot (money and grief) in the long run.
Better read up on this subject before you start this job if you haven't. It is one of those things which is more important than it might seem. As I understand it, bonding refers to the boats mechanical parts (rigging) and how they are electrically connected to each other (or not). There are different schools of thought on this subject. I would advise using the original plan as the boat was built. Grounding is an electrical term which is used in rather imprecise ways. Do not confuse the two. The main problem arises from very small DC voltage differences between these systems and the ensuing electrolytic corrosion. There can also be problems from dissimilar metals used for wiring connections. Generally, keep the DC ground separated from the AC ground and seperated from the "AC return". Do not connect the bonding system directly to the ground system(s). Improper grounding affects not only your own boat but your neignbors boat as well. The reverse is also true. The RF (radio) ground can be isolated from any DC component by using a capacitance isolation system. The coaxial cables shield is supposed to be an RF ground and sometimes causes problems if someone intentionally or inadvertantly connects it to the bonding system. Debra, I respectfully disagree about your assesment of soldered connections. Done properly with the proper amount of heat, correct (preferably eutectic) solder, and the right flux, it is probably the best wiring technique I know of. Use care not to allow solder to flow into the areas which are subject to mechanical flexing and it is far superior to any crimped connection I have ever seen. Either method works but both require the proper tools, technique, and attention to detail. Workmanship I have seen on boats is usually very poor and wiring is not labeled or routed with much if any attention or care. Do it right and it will save a lot (money and grief) in the long run.
B
Bob
Soldering
Patrick I agree, I think soldering is the most permanent connection, and coupled with heat shrink leaves the dryest connection. All the old wire is going, and I special ordered tinned copper spade connectors from Mcmasters Carr (about 1/10) the price of ancor at west marine. I will have to read some more on the bonding. Problem with the Blue Sea Panel is that you could put the directions and diagrams on the back of a match book.
Patrick I agree, I think soldering is the most permanent connection, and coupled with heat shrink leaves the dryest connection. All the old wire is going, and I special ordered tinned copper spade connectors from Mcmasters Carr (about 1/10) the price of ancor at west marine. I will have to read some more on the bonding. Problem with the Blue Sea Panel is that you could put the directions and diagrams on the back of a match book.
P
Patrick
Couple of more thoughts
1. Use inner wall melt heat shrink only. 2. Get a bucketful of toroids and use them up. That will reduce the electrical noise a lot and it will make your radio receivers work much better. Blue Sea makes good stuff but documentation is always a problem.
1. Use inner wall melt heat shrink only. 2. Get a bucketful of toroids and use them up. That will reduce the electrical noise a lot and it will make your radio receivers work much better. Blue Sea makes good stuff but documentation is always a problem.
Bob,
Bob, A.B.Y.C. frowns on soldering. It creates a hard point that is resistant to the flexing inherant on boats. A strong mechanical crimp with heat shrink is the way to go. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
Bob, A.B.Y.C. frowns on soldering. It creates a hard point that is resistant to the flexing inherant on boats. A strong mechanical crimp with heat shrink is the way to go. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
B
Bob
Toroidal cores and EMI
EMI - electro-magnetic interference A common problem with most rf generating equipment (transmitters, computers, dimmers, fluorescent lights, motors) is the radiated rf from the external leads attached to them. This is called rfi (rf interference) or emi (electromagnetic interference), and it can cause interference to the reception of TV or radio broadcasts, and even interfere with audio equipment. Apart from suppressing the source of the rfi, it is usually necessary to prevent the rf from entering the receiving equipment. Put an AM radio next to your computer and the noise interference you hear will likely be EMI from your computer. Likewise car ignition systems, alternators, and many other things electronic in nature will do the same thing. EMI can show up as pops, clicks, humming, buzzing, etc. in an audio system or snow on the screen of a TV. Toroid - a donut shape The toroids I am referring to are made from a ferrite material and work to reduce (filter) the EMI caused by various electrical devices like power supplies (ie: chargers and inverters), motors, appliances like microwaves, computers, instruments, etc. If you look at the video cable on your computer, digital camera interface cable, etc, you may see a cylinderical bulge in one or both ends which is not a feature of the connector. That is likely a toroid core which surrounds the cable and absorbs a lot of the electrical noise which would be emitted (or received) by the cable. Toroidal cores can be put on cables in your boat for reducing the inevitable problem of EMI which will doubtless interfere with radios using any kind of amplitude modulation such as AM broadcast signals, SSB, broadcast TV (video signal only), aircraft radios, etc. FM signals are less susceptible to this kind of interference. These toroids can be a made as solid cylinder with a hole in the middle (best IMO) or they are also made like a clam shell and will clamp around one or more cables. They are also made in other shapes which will suit a particular application like ribbon cable. They are more effective if you can loop the cable around the core a few turns (N). The N factor is squared in the mathematical formula so the more turns, the greater the effectiveness. They are relativley cheap and quite effective. Smaller clamp on ones are about $3 and larger are about $5. http://www.amidoncorp.com/aai_ferritesforrfi.htm http://www.amidoncorp.com/aai_emrfisupppression.htm http://www.fair-rite.com/
EMI - electro-magnetic interference A common problem with most rf generating equipment (transmitters, computers, dimmers, fluorescent lights, motors) is the radiated rf from the external leads attached to them. This is called rfi (rf interference) or emi (electromagnetic interference), and it can cause interference to the reception of TV or radio broadcasts, and even interfere with audio equipment. Apart from suppressing the source of the rfi, it is usually necessary to prevent the rf from entering the receiving equipment. Put an AM radio next to your computer and the noise interference you hear will likely be EMI from your computer. Likewise car ignition systems, alternators, and many other things electronic in nature will do the same thing. EMI can show up as pops, clicks, humming, buzzing, etc. in an audio system or snow on the screen of a TV. Toroid - a donut shape The toroids I am referring to are made from a ferrite material and work to reduce (filter) the EMI caused by various electrical devices like power supplies (ie: chargers and inverters), motors, appliances like microwaves, computers, instruments, etc. If you look at the video cable on your computer, digital camera interface cable, etc, you may see a cylinderical bulge in one or both ends which is not a feature of the connector. That is likely a toroid core which surrounds the cable and absorbs a lot of the electrical noise which would be emitted (or received) by the cable. Toroidal cores can be put on cables in your boat for reducing the inevitable problem of EMI which will doubtless interfere with radios using any kind of amplitude modulation such as AM broadcast signals, SSB, broadcast TV (video signal only), aircraft radios, etc. FM signals are less susceptible to this kind of interference. These toroids can be a made as solid cylinder with a hole in the middle (best IMO) or they are also made like a clam shell and will clamp around one or more cables. They are also made in other shapes which will suit a particular application like ribbon cable. They are more effective if you can loop the cable around the core a few turns (N). The N factor is squared in the mathematical formula so the more turns, the greater the effectiveness. They are relativley cheap and quite effective. Smaller clamp on ones are about $3 and larger are about $5. http://www.amidoncorp.com/aai_ferritesforrfi.htm http://www.amidoncorp.com/aai_emrfisupppression.htm http://www.fair-rite.com/
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