Best inverter for the buck

[mitiempo]

Bill

The last diagram from Pete that shows the transfer switch after the panel is from post #66. The only more recent diagram from Pete I can find is in post #109 and it shows the transfer switch before the panel - which would be my choice.

You have said that if the transfer switch is after the panel there are several more circuits to separate the 2 sources and that they need CB protection - water heater and battery charger. The water heater and charger are protected by the main panel breakers and will not see any current from the inverter in Pete's diagram. When the 2 pole switch is in the inverter position the main panel is not part of the circuit - just the inverter and outlets.

If the transfer switch is before the panel the same 2 pole switch is used and an additional breaker is not required. I posted the diagram (post #98) showing the switch from Blue Seas (PN 9009) and how it is wired before the panel - it is a 2 pole switch.

 

[Stu Jackson]

Inverter wiring & Safety

You seem to to always miss the point. ...Besides that you should have at least read my previous post

My apologies, Pete. I did note that I had not reviewed your newest diagram. The fuse you show at the inverter DC positive should be at the battery end of that wire. Gettin' there.

 

[prroots]

Getting back to my review of the Samlex SSW-1500-12A vs the Xantrex Prowatt SW1500 inverters, I have called tech support of each company. The Samlex tech support is infinitely better than the Xantrex. The rep from Samlex speaks authoritatively and seems to know the product well whereas the Xantrex rep simply could not answer my basic questions. This is despite the fact I called several times in order to get different reps. I did learn that hot and neutral are connected on the Samlex; it was a different model in which they were not connected. The Samlex is manufactured in Hong Kong whereas the Xantrex is manufactured in China. The Samlex is not conformal coated whereas Xantrex doesn't know. They weren't even sure what that meant. BTW, I have sent along a tech support ticket to Xantrex with the same questions hoping to get knowledgeable answers. The Samlex rep recommended that I go with Xantrex or Pro Mariner for my marine application! Can you imagine that? I would think that cinches it unless there is something I don't know about the two companies that would steer me the other way.

Unfortunately, the spot I had picked for the inverter is too small for the Xantrex since it is larger than the Samlex. This may force me to run the DC cables much further than I had planned.
Pete

 

[prroots]

Pete,

Unless your inverter has an integral breaker on the HOT 120V leg then you will probably still want a breaker. As it is drawn you are using the AC main breaker in the AC panel, which can be fine, but this requires your inverter wiring to be the same gauge. Eg: You can't protect 14GA wire with a 30A breaker...:neutral: Another example is that the ProWatt SW 2000 has a max draw if about 19A AC. You don't size for "max continuous" which is about 15A you always size for "max" amperage the device can support. Xantrex claims 19.2A or a 20A breaker and 12GA wire.

This means you can wire A ProWatt SW 2000 safely with 12GA wire to the ACTS switch. Here lies the issue. You should not protect a 12GA wire with a 30A breaker, which is very likely what your panel has. If it is 50A service this is even worse.. 12GA wire should be protected with a 20A breaker not a 30A or 50A.

The inverter AC wiring to the ACTS should be sized to handle the full output of the inverter which in this case is below what a 30A or 50A main AC breaker should protect. A 2000W inverter can do about 19 - 20A. If you run 10GA wire then your fine with the 30A breaker, the breaker is only protecting the wiring anyway, but if you run smaller than that you'll want an additional breaker in the hot leg of the inverter. If you have 50A service you'll be much better off with a 20A breaker & 12GA wire..
.

It appears I have two options based upon the fact that I've now selected the Xantrex Prowatt SW2000:

1. Use AWG 10 without separate breaker (ie, protected by 30A breaker of AC panel)
2. Use AWG 12 with separate 20A breaker on hot line of inverter output

I favor the former since it is simpler and only requires one step up in wire gauge (ie, from 12 to 10).

With all the feedback received, it would seem that I now able to select most all the components as follows:

• Sterling Power model SC32A transfer switch
• Yandina model GI-50N galvanic isolator
• Xantrex Prowatt SW2000 inverter
• Xantrex model 808-9001 remote control panel for inverter

I still need to select the DC cable and fusing. Xantrex recommends a 250A fuse. Given the maximum 6 foot round trip cable length a 2/0 105C cable looks good. It seems that the Blue Sea 5005 class ANL fuse holder will work for this amperage and cable size. Comments?
Pete

 

[Bill Roosa]

A final thought for you Pete:
There is the theory and there is the practice. I was asking myself why I'm resistant to your solution and quite frankly there is nothing wrong with it in theory. I believe when you get to actually bending metal you are going to find that your solution yields a less "pretty" solution on both sides of the panel. On the back side there will be lots of wires running all over the place with not much order or at least lots of wires running back and forth confusing their purpose. We all have seen the pictures of the tangle foot that some boats have for wiring. On the front side you will have either multiple panels or have to have some extra holes in odd places to get everything to fit and work right. The "look" will be cluttered and it will not be obvious at a glance what a person should do to change from SP to inverter power and back.
While there may be several ways to accomplish a task in theory, in practice only one lends itself to an acceptable solution.

Good luck.

 

[Maine Sail]

It appears I have two options based upon the fact that I've now selected the Xantrex Prowatt SW2000:

1. Use AWG 10 without separate breaker (ie, protected by 30A breaker of AC panel)
2. Use AWG 12 with separate 20A breaker on hot line of inverter output

I favor the former since it is simpler and only requires one step up in wire gauge (ie, from 12 to 10).

With all the feedback received, it would seem that I now able to select most all the components as follows:

• Sterling Power model SC32A transfer switch
• Yandina model GI-50N galvanic isolator
• Xantrex Prowatt SW2000 inverter
• Xantrex model 808-9001 remote control panel for inverter

I still need to select the recommended 250A fuse and associated fuse holder. Any recommendations for a low cost, but reliable choice?
Pete

Pete,
I do prefer the bolded option as it allows you to better "protect" the wire because the breaker is close to the source. It is also the "preferred" method and in alignment with current safety standards..

I like everything but the GI. Don't get me wrong I generally love Yandina products and tey stand behind the products. However, their GI's do not meet current safety standards. Do they work? Yes, but if they are taken out by a transient, lightning etc. you have no way to know it. GI's should either be of a "fail safe" design or have a light or control panel that tells you they are working and the ground is intact.

As much as I like the Yandina products I simply can't and will NOT open myself to that liability by installing one when A-28 has been sooo widely accepted due to LOTS of failures of GI's before they were "fail safe"... The last thing anyone wants is a dropped earth ground and not knowing about it.

The DEI Marine GI-30A-FSP, ProMariner #22034 & Guest 4531001 all meet the current ABYC A-28 July 2008 safety standards.


Feel free to read this article:
Argument For Fail Safe GI's

As for a fuse an ANL or class T is preferred for inverters. Blue Sea is the ONLY company making an ignition protected ANL so I mention that to save you the searching. I prefer their fuse blocks too.

 

[prroots]

Pete,
I do prefer the bolded option as it allows you to better "protect" the wire because the breaker is close to the source. It is also the "preferred" method and in alignment with current safety standards..

I like everything but the GI. Don't get me wrong I generally love Yandina products and tey stand behind the products. However, their GI's do not meet current safety standards. Do they work? Yes, but if they are taken out by a transient, lightning etc. you have no way to know it. GI's should either be of a "fail safe" design or have a light or control panel that tells you they are working and the ground is intact.

As much as I like the Yandina products I simply can't and will NOT open myself to that liability by installing one when A-28 has been sooo widely accepted due to LOTS of failures of GI's before they were "fail safe"... The last thing anyone wants is a dropped earth ground and not knowing about it.

The DEI Marine GI-30A-FSP, ProMariner #22034 & Guest 4531001 all meet the current ABYC A-28 July 2008 safety standards.


Feel free to read this article:
Argument For Fail Safe GI's

As for a fuse an ANL or class T is preferred for inverters. Blue Sea is the ONLY company making an ignition protected ANL so I mention that to save you the searching. I prefer their fuse blocks too.

Thanks. I edited my post after you replied apparently. I did select an ANL fuse block, 250 Amp fuse, and 2/0 105C cable. I'll study those fail-safe GI's.
Pete

 

[Maine Sail]

Thanks. I edited my post after you replied apparently. I did select an ANL fuse block, 250 Amp fuse, and 2/0 105C cable.
Pete

I see that. Please don't discount installing the right GI!!! Capt. David Rifkin (USN, Ret., AMS) is one of the leading guru's on boat corrosion and AC safety in the industry.


From David Rifkin (Quality Marine Services):

"In the many boats I have tested with galvanic isolators, approximately 5% tested open circuited (meaning the boat did not have a connection to the marina grounding system) and the operators were completely unaware.

Given the tens of thousands of isolators installed over the years, there may be thousands out there that have failed open circuited, establishing one of the two necessary accident conditions.

One of the problems is that galvanic isolators are seldom routinely tested for proper functioning, if ever. Even those isolators installed today that utilize monitoring may not report accurately if subject to a strong electrical transient (like an ac fault or lightning strike on or near the boat) and sometimes do not work properly even on new installations. Ideally, all boats would receive periodic maintenance that would include a check for a properly functioning galvanic isolator (it is unlikely this will happen any time soon).

However, there is a technically sound solution to this problem which came about through the development of a truly fail-safe isolator design that has been in use in the corrosion industry (outside of the boating industry) for years. Isolators not built with fail-safe construction cannot handle the energy associated with a large ac fault or lightning strike and consequently can, and in fact are allowed to, fail open-circuit.

Conclusion: Based on our research and experience, it is imperative that the continuity of the grounding wire system be intentionally assured at all times. The first step in maintaining this assurance is to install a truly fail-safe galvanic isolator in the boat’s AC grounding wire path."

 

[prroots]

I see that. Please don't discount installing the right GI!!! Capt. David Rifkin (USN, Ret., AMS) is one of the leading guru's on boat corrosion and AC safety in the industry.

Thanks again. I did read the article and it, of course, makes perfect sense to use fail-safe GI's. Of course, one should still periodically test the GI to be sure it hasn't failed in the safe mode, otherwise you are subject to galvanic corrosion without realizing it. Also, I would probably opt for the 50/60 Amp versions to cover both shore power services simultaneously as shown in my schematic
Pete

 

[prroots]

I see that. Please don't discount installing the right GI!!! Capt. David Rifkin (USN, Ret., AMS) is one of the leading guru's on boat corrosion and AC safety in the industry.

West Marine sells the
ProMariner 22074 ProSafe 50/60 Amp Failsafe Galvanic Isolator

Does this also satisfy the fail-safe requirement?
Pete

 

[Maine Sail]

West Marine sells the
ProMariner 22074 ProSafe 50/60 Amp Failsafe Galvanic Isolator

Does this also satisfy the fail-safe requirement?
Pete

Yes..

http://www.pmariner.com/productFeature.php?ProductNum=22074

 

[prroots]

The Yandina website states that you must install a remote monitor for their GI to meet ABYC standards. I called them and they stated that they don't provide the monitor nor do they know of a company that does. They stated that in 14 years, they've only had one return and that was due to a direct lightening strike. Comments?
Pete

 

[Snotter]

The Yandina website states that you must install a remote monitor for their GI to meet ABYC standards. I called them and they stated that they don't provide the monitor nor do they know of a company that does. They stated that in 14 years, they've only had one return and that was due to a direct lightening strike. Comments?
Pete

Didn't ABYC recently drop the requirement for a monitor?

 

[Maine Sail]

Didn't ABYC recently drop the requirement for a monitor?

Monitor or fail safe.... If you don't have a fail safe it needs to be monitored.

Proots,

It is quite likely that Yandina has not had many returns because people RARELY if ever check to see that the GI is working and just trust that it is.. I do commend Yandina for at least being honest on their web site and stating clearly that their GI does not meet current safety standards.. This is quite upstanding IMHO but I would still use a fail safe..

 

[prroots]

I have revised my standalone inverter design (see attached sketch). Some of the notable changes are:

1. Show AC transfer switch before AC panel
2. Show AC inverter output wire size as AWG 10/3 conductors
3. Show DC positive fuse close to battery as a 250 Amp class ANL fuse
4. Show DC cable wire size as AWG 2/0
5. Show galvanic isolator protecting two shore power connections
6. Show breaker sizes for all 3 AC loads

Most importantly, Maine Sail has convinced me to locate transfer switch before the AC panel so as to decrease fault potential. The negative is that it is now possible to inadvertently drain battery by feeding battery charger and/or water heater from inverter. The output cabling from inverter through AC transfer switch to AC panel has been sized in such a way that it is protected by the existing 30 Amp breaker (of AC panel) making it unnecessary to add still another breaker. Of course the wiring from AC panel to AC outlets will be protected by the existing 15 Amp breaker. The inverter itself will have overload protection. I have tentatively selected the Xantrex Prowatt SW2000 inverter. Xantrex recommends a 250 Amp fuse on the positive DC cable. I calculate that an AWG 2/0 cable of less than 3 feet length (one way) will be sufficient. Finally, I show a galvanic isolator protecting both shore power connections with rating increased to 50/60 Amps. Comments welcome.
Pete

 

[Maine Sail]

I have revised my standalone inverter design (see attached sketch). Some of the notable changes are:

1. Show AC transfer switch before AC panel
2. Show AC inverter output wire size as AWG 10/3 conductors
3. Show DC positive fuse close to battery as a 250 Amp class ANL fuse
4. Show DC cable wire size as AWG 2/0
5. Show galvanic isolator protecting two shore power connections
6. Show breaker sizes for all 3 AC loads

Most importantly, Maine Sail has convinced me to locate transfer switch before the AC panel so as to decrease fault potential. The negative is that it is now possible to inadvertently drain battery by feeding battery charger and/or water heater from inverter. The output cabling from inverter through AC transfer switch to AC panel has been sized in such a way that it is protected by the existing 30 Amp breaker (of AC panel) making it unnecessary to add still another breaker. Of course the wiring from AC panel to AC outlets will be protected by the existing 15 Amp breaker. The inverter itself will have overload protection. I have tentatively selected the Xantrex Prowatt SW2000 inverter. Xantrex recommends a 250 Amp fuse on the positive DC cable. I calculate that an AWG 2/0 cable of less than 3 feet length (one way) will be sufficient. Finally, I show a galvanic isolator protecting both shore power connections with rating increased to 50/60 Amps. Comments welcome.
Pete

Whoops I never caught the second shore power inlet...


ABYC E-11

11.5.3.6. When more than one shore power inlet
is used, the shore power neutrals shall not be
connected together on board the boat.

11.5.3.7. Individual circuits shall not be capable
of being energized by more than one source of
electrical power at a time. Each shore power inlet,
generator, or inverter is a separate source of electrical
power.

11.5.3.7.1. The transfer from one power
source circuit to another shall be made by a means that
opens all current-carrying conductors, including
neutrals, before closing the alternate source circuit,
and prevents arc-over between sources.

11.5.3.7.2. A means for disconnecting all
power sources from the load shall be provided at the
same location.

 

[woodster]

does this mean that the selector switch (sterling) 3 position switch will work .....

1st connection shore power #1 switch

2nd connection invertor #2 switch

3rd connection shore power #3 switch

regards

woody

 

[Maine Sail]

does this mean that the selector switch (sterling) 3 position switch will work .....

1st connection shore power #1 switch

2nd connection invertor #2 switch

3rd connection shore power #3 switch

regards

woody

Yes... But would not have worked in his original location which was down stream of the AC outlet breaker.....

 

[woodster]

Yes... But would not have worked in his original location which was down stream of the AC outlet breaker.....

the reason i ask is ...i am planning to do the inverter and also install the second shore power inlet in order to be able to hook up the honda gen set via a spare shore power cable and inlet.....

regards

woody

 

[prroots]

The second 30 Amp shore power connection is independent of the first one and used to supply power to two zone heat pumps so it's not an either or. It has it's own AC panel, etc.
Pete