Jedi AC power diagram: updated version 3

[s/v Jedi]

Here is the new version. What has changed is that the breakers for air conditioners and water heater have moved from the input panel (before inverter/chargers) to their own group after the inverter/chargers.

the reasons for this change:

1. You can still do the same setup where air conditioning and water heater only work on shore power or generator by setting Group 3 source to Bypass and enabling the input bypass breaker.

2. Big solar installations can now feed the water heater when batteries are full

3. New inverter-type air conditioners are so efficient that they can run from inverter.

This change does introduce an extra rotary switch that is hard to find, but there are 63A versions available on eBay that are affordable as well.

This diagram is custom tailored for us so a boat with all electric galley, large solar array, genset and visiting 3rd world as well as western civilizations

It can easily be modified, i.e. when you do not require your water maker to be able to run from inverter (you have DC powered or engine mounted pump) then you can remove that group.

This diagram allows a 60Hz boat to connect to 50Hz shore power and the other way around. You do that by switching the input breaker of inverter/charger 2 off (so that it goes to inverting) and select that Inverter 2 as source for all breaker groups. Inverter/charger 1 has input breaker on so charges the batteries but it's AC output isn't used as it is the wrong frequency.

[wingssail]

Originally Posted by s/v Jedi

Here is the new version. What has changed is that the breakers for air conditioners and water heater have moved from the input panel (before inverter/chargers) to their own group after the inverter/chargers.

the reasons for this change:

1. You can still do the same setup where air conditioning and water heater only work on shore power or generator by setting Group 3 source to Bypass and enabling the input bypass breaker.

2. Big solar installations can now feed the water heater when batteries are full

3. New inverter-type air conditioners are so efficient that they can run from inverter.

This change does introduce an extra rotary switch that is hard to find, but there are 63A versions available on eBay that are affordable as well.

This diagram is custom tailored for us so a boat with all electric galley, large solar array, genset and visiting 3rd world as well as western civilizations

It can easily be modified, i.e. when you do not require your water maker to be able to run from inverter (you have DC powered or engine mounted pump) then you can remove that group.

This diagram allows a 60Hz boat to connect to 50Hz shore power and the other way around. You do that by switching the input breaker of inverter/charger 2 off (so that it goes to inverting) and select that Inverter 2 as source for all breaker groups. Inverter/charger 1 has input breaker on so charges the batteries but it's AC output isn't used as it is the wrong frequency.

Pretty sweet. What I liked is that I could understand it within about 30 seconds when I expected it to be beyond me.

Unfortunately I don't understand the whole boat since the batteries, 12v, and solar systems are not shown. That's OK I don't need to understand.

Unfortunately 2, it's all esoteric to me since that level of equipment installation is totally the opposite of the simple, light, fast and low maintenance boat I run.

Unfortunately 3, VIP cabin? I'm also assuming you have an engineer's cabin, I think you might need one.

But, all in all, good job.

[s/v Jedi]

Originally Posted by wingssail

Pretty sweet. What I liked is that I could understand it within about 30 seconds when I expected it to be beyond me.

Unfortunately I don't understand the whole boat since the batteries, 12v, and solar systems are not shown. That's OK I don't need to understand.

Unfortunately 2, it's all esoteric to me since that level of equipment installation is totally the opposite of the simple, light, fast and low maintenance boat I run.

Unfortunately 3, VIP cabin? I'm also assuming you have an engineer's cabin, I think you might need one.

But, all in all, good job.

1) this is the AC diagram; you mention parts of the DC diagram which is separate and not needed for understanding the AC part.

2) which components do you not have? Genset? scratch it out. I bet you have the inverter charger and breakers, although I have seen boats without AC power, they are rare for cruisers.

3) VIP cabin is a guest cabin that has it’s own private vanity, hanging closet and head with shower. On our boat this is the only guest cabin as we only have beds for 4 people down below.
There are no other cabins than mentioned in the diagram.

[Auspicious]

Originally Posted by s/v Jedi

2. Big solar installations can now feed the water heater when batteries are full

3. New inverter-type air conditioners are so efficient that they can run from inverter.

2. This makes a very reasonable dump load for extra energy. This is another approach to hot water of a combined DC/AC heater element that SVHotwire sold for many years. Pros of Jedi: maintains full as-designed heat generation capacity in the water heater. Cons: efficiency losses through inverters, which aren't very relevant for a dump load.

3. I've seen a number of 5k BTU A/C units running off battery. As always energy taken out of storage (batteries) needs to be replaced. Given what I think I remember of Jedi operating practice it would be easy to get the bulk of the heat out of the boat during the evening generator run for dinner prep/battery charge/water-making and keep the boat cool and dehumidified until bedtime. Or was that Dockhead's operating practice? I forget. Still applies.

[s/v Jedi]

Originally Posted by Auspicious

2. This makes a very reasonable dump load for extra energy. This is another approach to hot water of a combined DC/AC heater element that SVHotwire sold for many years. Pros of Jedi: maintains full as-designed heat generation capacity in the water heater. Cons: efficiency losses through inverters, which aren't very relevant for a dump load.

3. I've seen a number of 5k BTU A/C units running off battery. As always energy taken out of storage (batteries) needs to be replaced. Given what I think I remember of Jedi operating practice it would be easy to get the bulk of the heat out of the boat during the evening generator run for dinner prep/battery charge/water-making and keep the boat cool and dehumidified until bedtime. Or was that Dockhead's operating practice? I forget. Still applies.

Lots of boats operate like that but I think I was the first one to describe it on this forum. But these new A/C units are different: you can run a 20kBTU unit from batteries all night long because, like inverter-type microwaves, they only consume power they need and do variable rpm.

I do not like DC elements for water heaters unless it is 48V or more.

[hzcruiser]

Originally Posted by s/v Jedi

Here is the new version. What has changed is that the breakers for air conditioners and water heater have moved from the input panel (before inverter/chargers) to their own group after the inverter/chargers.

That's a pretty extensive AC wiring loom you're running through the boat. Looks well thought out but also quite pricey to allow for all the inpt sources.

[s/v Jedi]

Originally Posted by hzcruiser

That's a pretty extensive AC wiring loom you're running through the boat. Looks well thought out but also quite pricey to allow for all the inpt sources.

We have an additional shore power that can be dropped by choosing one of the two. The three switches on the distribution groups cost $25 each so there’s about $100 extra cost. Building the panel instead of buying one saves $500-$1000 but when you already have a panel then this costs more again.

It’s like so many things where improving a current system that is still serviceable is a big step to take. Our boat is at the point it needs a new panel so this setup gets us the improvements based on our experience with the oem systems while saving money by building it ourselves

[hzcruiser]

Originally Posted by s/v Jedi

It’s like so many things where improving a current system that is still serviceable is a big step to take. Our boat is at the point it needs a new panel so this setup gets us the improvements based on our experience with the oem systems while saving money by building it ourselves

OK, so you already had all of those inverters and transformers on board. That makes a difference. A separate panel just for 110/220V ? Wow. My 2 panels are all 12V. 240V is only going to a few mains outlets via three breakers plus GFCI (ground-fault circuit interrupter) aka RCD.

[AndrewA2]

Can you help me understand what the AutoTransformer is used for?

I understand it can step up/down between 120v/240v however i see you have input as 240 (which is what my brain imagines it to do) but then has output of 120/240v (which is what i dont understand. do you have mixed 120/240 appliances? i am confused....)

The way i thought it works is taking a signal (120/240) then you set the output as either 120/240.... but i feel i am missing something....

[SVRocinante]

Originally Posted by s/v Jedi

...these new A/C units are different: you can run a 20kBTU unit from batteries all night long because, like inverter-type microwaves, they only consume power they need and do variable rpm...

Good day s/v Jedi
If you would be so kind as to point me in the direction of said A/C units, it would be greatly appreciated!

regards,

[s/v Jedi]

Originally Posted by AndrewA2

Can you help me understand what the AutoTransformer is used for?

I understand it can step up/down between 120v/240v however i see you have input as 240 (which is what my brain imagines it to do) but then has output of 120/240v (which is what i dont understand. do you have mixed 120/240 appliances? i am confused....)

The way i thought it works is taking a signal (120/240) then you set the output as either 120/240.... but i feel i am missing something....

An auto transformer can be used for many things but in this application it is used to create a Neutral conductor for American standard 120-0-120 wiring.

First what it is: a single winding with a center tap. This only makes sense for American standard 60Hz boats. US appliances that need high power, use 240V instead of 120V. So you normally have both and this comes as a 4-conductor cable:

L1 - hot, black
L2 - hot, red
N - grounded neutral, white
G - ground, green or bare conductor

Between L1 and N you have 120V
Between L2 and N you have 120V
Between L1 and L2 you have 240V

This is impossible to make with an inverter; some brands allow to connect two inverters to create this but the risk of problems is a multiple of a single inverter.

So for a boat you do what this diagram does:

- from a generator you only take the L1 and L2 conductors. Do not connect the N and remove ground wires from the N. Connect the genset ground point to ships ground with a separate cable. This means that output is always balanced and you get maximum genset capacity (unlike in a 120-0-120 connection where each leg can only take 1/2 the power maximum)

- from US 120/240V 50A shore power, only take L1 and L2. Use a galvanic isolator between shore ground and ships ground. Do not connect N

- from US 120V 30A, 20A, 15A shore power you get either L1 or L2 (so only one of them) and N. This is the difficult one and we use an isolation transformer. This blocks the ground wire and also doubles the input to 240V. You do not ground any of the output conductors.

- from EU 230V shore power you get the same deal as US 120V, i.e. a hot and a grounded neutral. We put that through the isolation transformer as well, jumpering it to 1:1 service instead of 1:2 so that voltage is not doubled.

Now you have a floating 240V and can use a single inverter/charger. High power devices can use that directly but for 120V you need to create a Neutral and this is what the auto transformer does. You connect this winding to the 240V and the center tap will provide 120V to each of L1 and L2. Now you can ground this new neutral to ships ground and you have a perfect setup for 60Hz American standard.

For 50Hz boats you don’t need any of that.

[s/v Jedi]

Originally Posted by hzcruiser

OK, so you already had all of those inverters and transformers on board. That makes a difference. A separate panel just for 110/220V ? Wow. My 2 panels are all 12V. 240V is only going to a few mains outlets via three breakers plus GFCI (ground-fault circuit interrupter) aka RCD.

It’s just a separate distribution group. The other groups don’t need the auto transformer because they are 240V only.

The groups are to distribute load over two inverter/chargers or to bypass them. Example: we have a big watermaker with a 1.5hp 240V motor. To run this on inverter, which we must be able to do when the genset is down, it needs the inverter all for itself. DC power can come from batteries or alternators or both.

When you connect to shore power in 3rd world countries, an isolation transformer is a must when you want to shield your boat from damage.

[s/v Jedi]

Originally Posted by SVRocinante

Good day s/v Jedi
If you would be so kind as to point me in the direction of said A/C units, it would be greatly appreciated!

regards,

Frigomar is the big name but there are more, like this one: Inverter driven self-contained units 230V-50/60Hz VSD. Reverse cycle function

[s/v Jedi]

These new A/C units are mostly unknown to cruisers, while all the small wall mount split units ashore already have this. Here a quote that explains it:

Self-contained-VSD air conditioners provides the best of the existing technology: compressor with brushless DC motor and inverter that constantly controls speed and cooling power delivered (Variable Speed Drive); reverse blade brushless fan; electronic expansion valve; R410A refrigerant.
Three sizes available: 10.000, 16.000, 21.000 and 27.000** BTU/h. The inverter technology, already used in residential airconditioning, offers the following benefits in marine applications:
• No current peaks during start-up
• Highest energy efficiency: overall reduction of electricity consumption (-40%)
• Perfectly running with small generators or battery powered
• Compressor noise and vibrations almost zero
• Constant temperature of the air flow
• Wi-fi connection for smartphone available through a dedicated app
The compressor continuously changes its running speed depending from ambient and set temperature. The compressor operates at maximum power to cool rapidly the cabins, but reaching the set temperature, it reduces the power and electricity consumption. In this way it maintains the optimal comfort level with the minimum consumption. The inverter works between 20 and 100 Hz.

[SVRocinante]

Originally Posted by s/v Jedi

Frigomar is the big name but there are more, like this one: Inverter driven self-contained units 230V-50/60Hz VSD. Reverse cycle function

Thanks.
This will be a great starting place; greatly appreciated!