Xantrex sw3000 installation questions

[rickoneil]

As I see it the sw3000 requires 2 AC line inputs, either split phase or 2 lines coming from a panel. In a typical 30 amp shore power, you don't have split phase, just hot neutral and ground. My installation as designed, would have a Blue Sea three source rotary AC switch, selecting shore power, generator and the third AC source, sw3000 inverter/charger.

My research has shown that typical inverter installations in boats and RV's have the inverter AC outs feeding a dedicated inverter load panel. That's how it is in my Bounder Diesel Pusher RV, it passes thru the AC in to the AC outs. But the problem with that is you have a limited amount of AC outlets fed from the inverter AC outs (obviously there is a current limitation). The good thing in the internal transfer switch is supposed to transfer from input AC power to inverter AC service smoothly. I can see the design that RV's have but I'd like to hear from cruisers who have installed these units and how they were wired in.

One danger that should be mentioned is the possibility of back feed where a AC panel feeds an inverter that is currently feeding that AC panel. I want to have one AC panel, with 2 lines/breakers feeding the sw3000 inverter/charger, and use the 3-way AC source selection, choosing shore power, genset or inverter. I could wire up a second switch before the AC line ins of the inverter as an idiot check to avoid back feed, but is there another way to do this?

Additionally, the sw3000 manual says that the AC input and AC output isolation should be maintained, for example, the neutrals from the AC in and AC outs should not be routed to common neutral bus. If the neutrals are eventually connected to ground and to each other, how can they be truly isolated?

This is my first post and I am currently in the "almost launched" phase of a refit of an 1978 Ericson 34T. I installed a Beta Marine Beta 28 with saildrive, no more shaft!

Rick O'Neil
Port Charlotte, Florida

[gordwedman]

One reason I have hesitated in getting a newer inverter is that I do not want an auto transfer switch. My setup has a circuit breaker panel with an interlock that slides up to lock out the shore power AC. You must shut off the shore power AC, slide up the lock and click over the breaker for the inverter. I really don't want to re-do this.

[GWB]

Originally Posted by rickoneil

As I see it the sw3000 requires 2 AC line inputs, either split phase or 2 lines coming from a panel. In a typical 30 amp shore power, you don't have split phase, just hot neutral and ground. My installation as designed, would have a Blue Sea three source rotary AC switch, selecting shore power, generator and the third AC source, sw3000 inverter/charger.

My research has shown that typical inverter installations in boats and RV's have the inverter AC outs feeding a dedicated inverter load panel. That's how it is in my Bounder Diesel Pusher RV, it passes thru the AC in to the AC outs. But the problem with that is you have a limited amount of AC outlets fed from the inverter AC outs (obviously there is a current limitation). The good thing in the internal transfer switch is supposed to transfer from input AC power to inverter AC service smoothly. I can see the design that RV's have but I'd like to hear from cruisers who have installed these units and how they were wired in.

One danger that should be mentioned is the possibility of back feed where a AC panel feeds an inverter that is currently feeding that AC panel. I want to have one AC panel, with 2 lines/breakers feeding the sw3000 inverter/charger, and use the 3-way AC source selection, choosing shore power, genset or inverter. I could wire up a second switch before the AC line ins of the inverter as an idiot check to avoid back feed, but is there another way to do this?

Additionally, the sw3000 manual says that the AC input and AC output isolation should be maintained, for example, the neutrals from the AC in and AC outs should not be routed to common neutral bus. If the neutrals are eventually connected to ground and to each other, how can they be truly isolated?

This is my first post and I am currently in the "almost launched" phase of a refit of an 1978 Ericson 34T. I installed a Beta Marine Beta 28 with saildrive, no more shaft!

Rick O'Neil
Port Charlotte, Florida

The neutrals are only connected to ground at the source of power and they are also switched. (When selecting power source)

[rwidman]

Originally Posted by gordwedman

One reason I have hesitated in getting a newer inverter is that I do not want an auto transfer switch. .................. .

So buy one that doesn't have this feature. Problem solved.

[rwidman]

Originally Posted by rickoneil

As I see it the sw3000 requires 2 AC line inputs, either split phase or 2 lines coming from a panel. In a typical 30 amp shore power, you don't have split phase, just hot neutral and ground. My installation as designed, would have a Blue Sea three source rotary AC switch, selecting shore power, generator and the third AC source, sw3000 inverter/charger.

My research has shown that typical inverter installations in boats and RV's have the inverter AC outs feeding a dedicated inverter load panel. That's how it is in my Bounder Diesel Pusher RV, it passes thru the AC in to the AC outs. But the problem with that is you have a limited amount of AC outlets fed from the inverter AC outs (obviously there is a current limitation). The good thing in the internal transfer switch is supposed to transfer from input AC power to inverter AC service smoothly. I can see the design that RV's have but I'd like to hear from cruisers who have installed these units and how they were wired in.

One danger that should be mentioned is the possibility of back feed where a AC panel feeds an inverter that is currently feeding that AC panel. I want to have one AC panel, with 2 lines/breakers feeding the sw3000 inverter/charger, and use the 3-way AC source selection, choosing shore power, genset or inverter. I could wire up a second switch before the AC line ins of the inverter as an idiot check to avoid back feed, but is there another way to do this?

Additionally, the sw3000 manual says that the AC input and AC output isolation should be maintained, for example, the neutrals from the AC in and AC outs should not be routed to common neutral bus. If the neutrals are eventually connected to ground and to each other, how can they be truly isolated?

This is my first post and I am currently in the "almost launched" phase of a refit of an 1978 Ericson 34T. I installed a Beta Marine Beta 28 with saildrive, no more shaft!

Rick O'Neil
Port Charlotte, Florida

If you don't understand how to install an inverter in a boat, you should leave this to a pro. Also, you should select an inverter that is compatible with your electrical system, not select an inverter and then try to find a way to make it fit your system.

By bringing in a pro before you purchase the equipment, you can save a lot of trouble and expense.

If you have some aversion to hiring a pro, you should take some courses in electricity and wiring until you learn what you need to know to do the installation yourself.

[foggysail]

Originally Posted by gordwedman

One reason I have hesitated in getting a newer inverter is that I do not want an auto transfer switch. My setup has a circuit breaker panel with an interlock that slides up to lock out the shore power AC. You must shut off the shore power AC, slide up the lock and click over the breaker for the inverter. I really don't want to re-do this.

I wired in a couple of double pole, double throw switches to do the transfers on one of our inverters. Got to be a BPIA remembering to change switches. Finally put a stop to that nonsense and wired together a relay with an indicator light that automatically changes the AC output from the inverter when dock or generator power is unavailable. But whatever satisfies your needs---

[gordwedman]

Originally Posted by rwidman

So buy one that doesn't have this feature. Problem solved.

So perhaps you could be so kind as to recommend a quality unit that doesn't have this "feature". Seems all the latest model pure sine wave inverters have this.

[rwidman]

Originally Posted by gordwedman

So perhaps you could be so kind as to recommend a quality unit that doesn't have this "feature". Seems all the latest model pure sine wave inverters have this.

I am not in a position to recommend one, but how about just not using the automatic transfer switch feature? That should do it.

[colemj]

Exeltec make inverters with optional transfer switches.

But I don't see the point here. All transfer switch inverters I have ever used have the ability to turn off the transfer switching and use as a straight pass through. The transfer switch is there, but you don't have to use it.

Mark

[evm1024]

Originally Posted by rickoneil

As I see it the sw3000 requires 2 AC line inputs, either split phase or 2 lines coming from a panel. In a typical 30 amp shore power, you don't have split phase, just hot neutral and ground. My installation as designed, would have a Blue Sea three source rotary AC switch, selecting shore power, generator and the third AC source, sw3000 inverter/charger.

SNIP >%


Rick O'Neil
Port Charlotte, Florida

Hi Rick,

I have a SW3000 and the installation manual is confusing in this regards. It took a bit of reading and research to get it figured out. The unit can be wired to a single 120vac input and will either feed through 120 v shore power to your AC panel or act as an inverter feeding that same panel.

I'll dig around on the boat next time I am there and get the "solution" references for you. an't remember if it is tape off the 2nd AC input or ....

On my boat I wire shore power to a 30 amp dual breaker (hot and neutral) which feeds the inverter. This shore power panel also has a single 15 breaker that is wired to a dedicated outlet for space heaters and the like.

The inverter AC output feeds the main AC panel through a 30 amp dual breaker. This then feeds individual 15 amp circuits to the various outlets inthe boat.

When on shore power both 30 A dual breakers are on and the inverter feeds through. When disconnected from shore power the inverter supplies the same set of individual breakers/outlets.

If I had a generator I would install a transfer switch either in the input side of the inverter or the output side of the inverter. I would need to do a little research to see which would be better for me and recommended for my inverter.

Regards

[evm1024]

Originally Posted by rwidman

If you don't understand how to install an inverter in a boat, you should leave this to a pro. Also, you should select an inverter that is compatible with your electrical system, not select an inverter and then try to find a way to make it fit your system.

By bringing in a pro before you purchase the equipment, you can save a lot of trouble and expense.

If you have some aversion to hiring a pro, you should take some courses in electricity and wiring until you learn what you need to know to do the installation yourself.

Being a research systems engineer and having done a little work on Power Grids I tend to think that I am qualified to install an inverter. If I had one that failed for example I could troubleshoot it to the component level and repair it. Given that I did find the manual for this specific inverter confusingI can understand why the OP has questions. It was as if they had left out some information and mis-stated other. Perhaps it was only the translation from the original technical writers language to english that failed.

Reminds me of the translation for a bridge project where "hydraulic ram" became "wet sheep".

I'm sure that your advise is well thought out and well intentioned but I would suggest (with all due respect) that you hire a professional writer so as to be sure that you do not come across with unintended offense.

[rwidman]

Originally Posted by evm1024

.............. I would suggest (with all due respect) that you hire a professional writer so as to be sure that you do not come across with unintended offense.

One of us should do that but I don't think it's me.

Why did you think it was necessary to add that comment? It adds nothing to the thread and is nothing more than a poorly veiled insult.

[evm1024]

Originally Posted by rwidman

One of us should do that but I don't think it's me.

Why did you think it was necessary to add that comment? It adds nothing to the thread and is nothing more than a poorly veiled insult.

Hi Ron,

I debated quite a bit about leaving that part in or taking it out. Decided to cast caution to the wind and left it in.

You might note that the comment in question mirrors your comments about hiring a pro in general style. And you might also note that you took exception to having this style applied to you.

Poorly Veiled insult? Not really but you can take it that way if you like.

I found your post condescending to the OP And in good humor thought to point that out.

As to my post not adding anything to the conversation - that is debatable. Some might say that as the only one else who has this specific inverter and having run into the same problem as the OP you might say that I am the only one who had something to add to the conversation....

Regards

[rwidman]

Originally Posted by evm1024

........... I found your post condescending to the OP And in good humor thought to point that out...........

You know, I don't care what you think about my post. I'm trying to help, that's all.

As for this "transfer switch" problem, I don't know why someone wouldn't want to use that feature, but it seems to me that if you don't supply power to the input, the inverter will always supply power to the output circuit because it "thinks" the power has failed.

Sometimes people over think things.

[Stu Jackson]

Man, it's not even the full moon yet and some are getting unnecessarily cranky.

From what I've read here, I'm not sure whether the OP wants to not use the built in auto transfer switch or not. That's all I've taken from this discussion.

It would be intyeresting to learn if the unit has two different ways to wire it.