Electrical distribution question

[FlyingCloud1937]

Originally Posted by goboatingnow

I built a prototype electronic central breaker panel a few years ago. Using E.T.A. Electronic switches. Similar idea but not distributed. I think distributed systems in under 50 footer don't make sense.

Dave

Now I have a 50 foooooter.

There is no way I could justify a real Marine Distributed Power System.

My Engines are aft, My Bat's are a Mid-Ship, SP-1 is STB 3/4, and my AFT SP is 3/4 FWD.

I have 12 AC circuits from the inverter, and 4 not.

I have 1 big DC circuit at the bow, and one mid-ship, 2 counting my new whistles(actually the whistles don't need anything, but the air-comp...) does..but it's also amid-ship.

I design/build ON-Board Power Systems for Yachts. The only time I think I can go distributed is if it's a 75 X18. With a full time skipper and a full time engineer.

Anybody under 75ft usually doesn't have a full-time engineer. And I find few owners or rented skippers that qualify as a full time ENGa..n......r's.

Hell... I don't let many fish-boat engineer's have at it.

Lloyd

[Lake-Effect]

Originally Posted by cal40john

I'm going in between the two extremes. I have added a sub fuse panel up forward. One big pair of wires to the forward panel and split everything out there.

Good idea. I have no opposition to a distributed approach, though I think in most boats under, say, 35 ft, there's no real cost savings or advantage to subpanels vs one single panel.

I would not have a DC electrical distribution system that relies on active electronics.

[Andina Marie]

Why did you purchase a boat? To tinker with and install gadgets or go sailing?

I fall into the former category to the detriment of the latter.

I spent the first 3 years restoring the boat and making it look immaculate.

It only stays immaculate for a short time if you use your boat for sailing.

The guy that sold me the boat scaled down to a somewhat ugly houseboat but during the years that I was refurbishing he put over 15,000 miles on his houseboat.

Next time I will stick to the KISS principle and spend more time sailing.

[CharlieJ]

Distributed power systems, aka "Three Wire Boat", were gaining a great deal of traction from some very big players in the electrical equipment manufacturers game; e.g., Siemens, MasterVolt/BEP, Carling, PanelTronics, etc. until almost all momentum was lost during the recession. Calder not only wrote about the system, he installed the Capi2 system on Nada, the sail boat that he used during the HyMar Project.

The major players that I am aware of now are:
ePlex
Capi2
CZone

There are others, I am sure, but it seems that these three have risen to the top.

The modules have been made more and more robust and the last iteration of the ePlex modules includes purpose built communication cabling that provides moisture ingress protection. The modules themselves are blocks of epoxy.

As far as "get home" capability, each channel on the modules by manufacturers that I am aware of provide an ATO fuse that can be used to bypass the electronics for that channel should a channel fail. It would be inconvenient, but it would get you home.

Regarding the AIC rating of the MOSFET electronic circuit breakers: Calder deliberately shorted out a channel with a heavy screwdriver with a clamp meter on the conductor in an attempt to measure the short circuit current. As I recall, the MOSFET tripped so fast when the short was applied that the max. current observed was the set point of the MOSFET. The ABYC has not totally accepted this yet, BTW.

[Maine Sail]

Originally Posted by FlyingCloud1937

A couple of manufactures have just that. I remember a few years ago a few of big expensive CATs had the systems installed from the factory.

At one time all three boats were dead in the water shortly after delivery. It took months to a year to get it sorted. I quit following the saga, and do know what the final outcome was.

Calder, did a couple of mag stories touting the benefits.

BEP had a partial system called the C-Zone System. I don't see them advertising that anymore.

Carling Technologies has the OctoPlex System.

Lloyd

OctoPlex

Don't even get me going on my customers Grand Banks Europa.......... He wound up selling the boat...... Even under warranty they could not get it right...

[goboatingnow]

Distributed power distribution systems are somewhat a subset of Distributed switching systems.

In my case I was more interested in a Digital circuit breaker system in a central panel. The advantages I saw were


1. The actual panel could be positioned anywhere , with a small mimic at the nag table
2. Reprogrammable electronic circuit breakers , allowed tight CB limits
3. System could use current profiling for error, wear, filament failure detection , as well as a good "equipment on" indication
4. plug out modules ( in my E.T.A) allowed easier repair. and even a conventional CB could be installed in a push
5. current monitoring metrics allowed better profiling of on board use.
6. Compatible with ordinary on.off switches


Distributed switching systems have several issues in a sub 50 foot boat

1. the need to run a large high current power ring bus around the boat, which is expensive and cumbersome

2. Sensitivity to load dumping

3. Possibility of switching modules in inaccessible areas

4. complexity, control is lost if module fails

5. Lots of connectors on the power bus, point of failure

6. incompatible with conventional on off switches , requires sender modules

Dave

[goboatingnow]

Calder, did a couple of mag stories touting the benefits.

well actually he touted a lot of issues and problems and really said the system wasn't ready for prime time use.

dave

[Lake-Effect]

Originally Posted by CharlieJ

Regarding the AIC rating of the MOSFET electronic circuit breakers: Calder deliberately shorted out a channel with a heavy screwdriver with a clamp meter on the conductor in an attempt to measure the short circuit current. As I recall, the MOSFET tripped so fast when the short was applied that the max. current observed was the set point of the MOSFET. The ABYC has not totally accepted this yet, BTW.

The ABYC has limited resources. I don't think they actually have a testing/certification capability for new equipment; the best they can do is to examine existing certifications and make reference to them when appropriate. So in the case of something like MOSFET active breakers, these devices would need to achieve some other level of certification, before the ABYC would consider them appropriate.

Much as I'm a fan of Nigel's, his screwdriver and a loop-current ammeter do not a certification make.

[wingless]

A MOSFET is an inappropriate device for current protection. The failure mode for a MOSFET is a closed / shorted condition. A MOSFET must vaporize the internal nickel electrical path, by expelling smoke and flame from the package, before the failure mode stops conducting.

[Colin A]

There are a number of distributed power (or multiplex or digital switching) systems out on the market, and as Charlie mentioned there were more before. The company I work for has experience with a wide range of these systems over the past 10 years on boats from as small as 29' up to well over 100'.
All the systems are a little different from one another but largely try to accomplish the same thing. Which is to de-centralize the control of power around the boat. Most of the systems use some variation of CAN network (Nmea 2000 or J1939) others use their own proprietary network.
The original poster mentioned using inline fuse in addition to the electronics for fault. Based on my experience this is probably a good idea especially if you offer a bypass around the electronics for emergencies. Although I must admit even on the system with no back up fusing I can only think of one or maybe two cases where an out put failed closed rather than open.
Some one mentioned the ETA electronic circuit breakers (not to be confused with their powerplex system). I have a demo kit sitting on my desk right now for these and I admit they are rather cool but a little pricey for DIY. I did hear that a boat was built at Lyman Morse a few years ago that used a bunch of them.
On the small boat you would be surprised how many sub 30 ft power boats have a basic distributed power system. Digital Switching Systems sold a system for most of the past 10 years that was installed in thousands of small Searays and ski boats. But these systems were pretty basic consisting of usually one control keypad and 2-3 power distribution modules.
Here is a partial list of systems we have seen.
ETA powerplex
E-plex
C-zone(BEP)
Mastervolt masterbus
Digital Switching Systems
Carling Octoplex
Navy Bus
Capi2
Empirbus

There are more I just can't think of them off the top of my head as well as least a half dozen other ones that are NLA.

[Colin A]

I should also mention, one of the purposed benefits of distributed power is saving on wire and weight. In my experience this is hard to achieve is a custom or semi custom boat (it can be done but it requires different thinking) . The target was the automotive industry that had found a sizable savings in cars by using CAN bus driven digital switching over older conventional systems (thou still retaining conventional fuses). The only boat companies that achieved these gains did a clean sheet design of their systems around distributed power on higher volume boats.

[CharlieJ]

well actually he touted a lot of issues and problems and really said the system wasn't ready for prime time use.

In a one on one discussion with Nigel he did tell me that the Capi2 system worked in accordance with specs once they went through the system and found where the installer had applied power to the signal conductor! Problem solved, system works.

[goboatingnow]

Originally Posted by wingless

A MOSFET is an inappropriate device for current protection. The failure mode for a MOSFET is a closed / shorted condition. A MOSFET must vaporize the internal nickel electrical path, by expelling smoke and flame from the package, before the failure mode stops conducting.

Power mosfets are very rugged with positive temperature coefficients. A simple fuse can act as an ultimate backup for severly electrically over stressed ( EOS) situations. They are commonly used in ECB applications

Dave

[goboatingnow]

Originally Posted by Colin A

There are a number of distributed power (or multiplex or digital switching) systems out on the market, and as Charlie mentioned there were more before. The company I work for has experience with a wide range of these systems over the past 10 years on boats from as small as 29' up to well over 100'.
All the systems are a little different from one another but largely try to accomplish the same thing. Which is to de-centralize the control of power around the boat. Most of the systems use some variation of CAN network (Nmea 2000 or J1939) others use their own proprietary network.
The original poster mentioned using inline fuse in addition to the electronics for fault. Based on my experience this is probably a good idea especially if you offer a bypass around the electronics for emergencies. Although I must admit even on the system with no back up fusing I can only think of one or maybe two cases where an out put failed closed rather than open.
Some one mentioned the ETA electronic circuit breakers (not to be confused with their powerplex system). I have a demo kit sitting on my desk right now for these and I admit they are rather cool but a little pricey for DIY. I did hear that a boat was built at Lyman Morse a few years ago that used a bunch of them.
On the small boat you would be surprised how many sub 30 ft power boats have a basic distributed power system. Digital Switching Systems sold a system for most of the past 10 years that was installed in thousands of small Searays and ski boats. But these systems were pretty basic consisting of usually one control keypad and 2-3 power distribution modules.
Here is a partial list of systems we have seen.
ETA powerplex
E-plex
C-zone(BEP)
Mastervolt masterbus
Digital Switching Systems
Carling Octoplex
Navy Bus
Capi2
Empirbus

There are more I just can't think of them off the top of my head as well as least a half dozen other ones that are NLA.

I used these ETA devices http://www.e-t-a.com/products/relays...s/p/e-1048-8c/, 20 euros a pop

Dave

[rimskych]

Originally Posted by Colin A

There are a number of distributed power (or multiplex or digital switching) systems out on the market, and as Charlie mentioned there were more before. The company I work for has experience with a wide range of these systems over the past 10 years on boats from as small as 29' up to well over 100'.
All the systems are a little different from one another but largely try to accomplish the same thing. Which is to de-centralize the control of power around the boat. Most of the systems use some variation of CAN network (Nmea 2000 or J1939) others use their own proprietary network.
The original poster mentioned using inline fuse in addition to the electronics for fault. Based on my experience this is probably a good idea especially if you offer a bypass around the electronics for emergencies. Although I must admit even on the system with no back up fusing I can only think of one or maybe two cases where an out put failed closed rather than open.
Some one mentioned the ETA electronic circuit breakers (not to be confused with their powerplex system). I have a demo kit sitting on my desk right now for these and I admit they are rather cool but a little pricey for DIY. I did hear that a boat was built at Lyman Morse a few years ago that used a bunch of them.
On the small boat you would be surprised how many sub 30 ft power boats have a basic distributed power system. Digital Switching Systems sold a system for most of the past 10 years that was installed in thousands of small Searays and ski boats. But these systems were pretty basic consisting of usually one control keypad and 2-3 power distribution modules.
Here is a partial list of systems we have seen.
ETA powerplex
E-plex
C-zone(BEP)
Mastervolt masterbus
Digital Switching Systems
Carling Octoplex
Navy Bus
Capi2
Empirbus

There are more I just can't think of them off the top of my head as well as least a half dozen other ones that are NLA.

AFAIK, Digital Switching Systems cease their productions of Power Management Enclosures. Now they only make keypads.