Distributed Electrical Systems or Standard Panel? Which do you like?

[rgleason]

I have not read the entire thread, but I believe the OP is talking about a distributed system that has a main backbone of wiring with devices tapping into that each device with control wiring at a central panel, and remotely activated CB/relay. I went to a seminar sponsored by OceanPlanet years ago about this.

[Chotu]

Originally Posted by rgleason

I have not read the entire thread, but I believe the OP is talking about a distributed system that has a main backbone of wiring with devices tapping into that each device with control wiring at a central panel, and remotely activated CB/relay. I went to a seminar sponsored by OceanPlanet years ago about this.

Close, but not quite.

I’m talking about the first part of what you said. The backbone.

Then tapping off the backbone are just supply lines for the distributed small breaker panels where they are needed and close to the items they are powering.

Hence the name: distributed (rather than centralized)

For instance, all the running light and anchoring light controls are at the helm. The small breaker panel at the helm controls all those and the panel obtains it’s power from the backbone.

The breaker panel near the head controls things in the head, etc etc.

[NPCampbell]

Originally Posted by noelex 77

Not if you have a dual pole distribution system, as we have . Admittedly these are not common, but this wiring system is fitted to most aluminium vessels.

Its main function is to reduce the chance of stray current corrosion, but it also has some significant advantages in reducing the fire risk. It does add some redudancy to the ground connection and slightly extra protection against lightning damage, but I think this is a very marginal benifit.

A bad lightning strike is still likely to take out all your electronics.

I'm an advocate for digital switching but the only additional protection it provides from lightning is that solid state relays are typically optically isolated from the switched load. So if lightning travels down the input line it will be marginally protected from taking out the device that it switches. That said, lightning just traveled over a mile+ air gap to get to you. Another 1/16 of an inch of any material is not going to stop it.

[NPCampbell]

Originally Posted by Chotu

Addressing the off topic topic, I can’t see why I’d go through all the trouble, wiring and complexity involved with digital switching after having googled it out of curiosity.

I’m already having misgivings about my digital shower control.

I am using one of the temperature controlled mixers that puts out a given temperature you select. It’s mechanical but is precise.

I need to turn on both the hot and cold water to flow to this mixer and pause it during a shower to save water.

However, there is no good looking mechanical valve system I can use in the shower for this.

I’m left with building an electronic control panel and solenoid valves. I also have a momentary electrical switch to use to pump out the shower drain.

There is no other option available that looks good. So I forced to use all this electronic stuff. I’m not looking forward to fixing it all as it breaks. It’s also a lot of time consuming crap to install. Seems like the digital switching is similar to the digital shower I have going on

In my personal experience, capacitors and mechanical relays are about the only thing on electronic boards that don't tend to age well. Solid state relays in digital switching circuits typically have MTBFs of several million hours. Compared to a power relay like your windlass uses, SSRs are vastly superior. They don't require debouncing, they have no inductive noise, no spark noise, and no coil or contacts that can corrode or stick. About their only drawback is cost and small leakage currents across their inputs.

[noelex 77]

Originally Posted by NPCampbell;‪3327660‬

I'm an advocate for digital switching but the only additional protection it provides from lightning is that solid state relays are typically optically isolated from the switched load. So if lightning travels down the input line it will be marginally protected from taking out the device that it switches. That said, lightning just traveled over a mile+ air gap to get to you. Another 1/16 of an inch of any material is not going to stop it.

I was not referring to digital switching, but rather a dual pole system with conventional switches and wiring. Dual pole systems can be traditional or digital.

Our dual pole system is not installed for lightning protection and I agree that it provides only marginal extra benefit in this area. However, we suffered a lightning strike on our previous boat and all the electronic equipment that was off survived and all the equipment that was on at the time of the strike was destroyed. This boat also had a traditional, non digital dual pole electrical system and having the negative side disconnected on the devices that were switched off was likely of some benefit. Keep in mind this was hardly a controlled experiment, but I have no desire to repeat the experience to reach a more statistically significant conclusion .

[noelex 77]

Traditional wiring systems have components such as switches that are more resistant to damage from transient high voltage events than the solid state components. I doubt this has much practical effect on the very high energy of typical lightning strikes. Lightning can easily fry traditional wiring and switches, but there are other more common causes of high voltage spikes on boats.

For example, if an alternator becomes disconnected (perhaps from a fuse blowing) while some of the electronics (such as the alternator diodes and regulators) may be damaged, any traditional wiring, switching etc is very unlikely suffer any problems or need repair. I wonder if the same is true of digital distribution systems?

[Chotu]

Here’s a data point about electronics. Another one. I have a couple of really good generators. I’ve gone through a bunch that were not reliable and finally found ones that are bulletproof. At least as far as the engine goes. They are Honda based generators. With a different powerhead on them. I use them for primary power. The same way you would use a northern lights generator. Thousands of hours. And they just keep going. On ethanol gasoline. With a carburetor. It’s a miracle. I have no idea why. But they work exceptionally well.

In any case, one of them has recently failed. It is only producing 90 V instead of 120. And it’s intermittent. Guess what? It’s the AVR complicated circuit board that is no good. Nothing else on the generator is wrong. Of course just the electronic control unit. That’s all that ever seems to go bad in anything these days. Just another data point for that off topic discussion we were having about the reliability of electronics.

I’ll add a second additional data point. There is a performance enhancing package on my truck. From the company edge. It is also malfunctioning in an annoying way. And guess what? It’s the circuitboard again.