inverter questions

Not really my area but I am at work with lots to do so I thought I would hang out at Club Sea Ray for a while and chime in.
What about the Ryobi 2200 generator/inverter. Several of the guys that I bought with have generators on their boats (32 to 37ft). They bought the Honda 2000EU and use them on their boats. I had thought about buying one as well but some 8 years ago for my SR 270 Sundancer (No Genny). I now have the 40ft with a generator and I think from what I have seen, heard and lifted I will buy the Fyobi 2200.
Just my two cents - Ok back to work - for now.
 
I was thinking about those Honda's as I thought they were the lightest and quietest but that would still be a pain in the ass. Dragging it down to the boat, pluss they are expensive. I have a Generac that powers my hole house in case of an outage and it was a little more than half of the E2000 Honda. I think after reading what old vet said I could wire it directly into my transom locker directly to the batteries and make a.short cord that goes to my shore power plug inside the locker. Never see it, safe.from weather and seas and I could turn it on when I need it. It would most likely be for using the microwave to make coffee in the morning, heating up something real quick and to heat up a bottle (our first is due in Nov). I wouldn't be running the stove tops or be on for more than 5 minutes at a time anyway. I am looking for a 12volt TV and if I have to I can just use a laptop to run the blu ray and input it to the tv for better viewing and sou.d.
 
AFD said:
I was thinking about those Honda's as I thought they were the lightest and quietest but that would still be a pain in the ass. Dragging it down to the boat, pluss they are expensive. I have a Generac that powers my hole house in case of an outage and it was a little more than half of the E2000 Honda. I think after reading what old vet said I could wire it directly into my transom locker directly to the batteries and make a.short cord that goes to my shore power plug inside the locker. Never see it, safe.from weather and seas and I could turn it on when I need it. It would most likely be for using the microwave to make coffee in the morning, heating up something real quick and to heat up a bottle (our first is due in Nov). I wouldn't be running the stove tops or be on for more than 5 minutes at a time anyway. I am looking for a 12volt TV and if I have to I can just use a laptop to run the blu ray and input it to the tv for better viewing and sou.d.
Click to expand...

If you haven't bought the Microwave yet. Then when you shop for it, pay attention to the Power Consumption, wattage. The lower the the wattage the less drain on your batteries from the invertor. I think I said earlier we had a customer fitting an 1100W microwave, that draw is just ridiculous.

I just did a quick google on compact microwaves and found a site listing their 6 best choices. 4 were 700W, 2 were 800W.. 700W / 12 = 58.33Amps 800W / 12 = 66.666Amps

When they first came out they were 500, then 550 then 600.....
 
AFD said:
I was thinking about those Honda's as I thought they were the lightest and quietest but that would still be a pain in the ass. Dragging it down to the boat, pluss they are expensive. I have a Generac that powers my hole house in case of an outage and it was a little more than half of the E2000 Honda. I think after reading what old vet said I could wire it directly into my transom locker directly to the batteries and make a.short cord that goes to my shore power plug inside the locker. Never see it, safe.from weather and seas and I could turn it on when I need it. It would most likely be for using the microwave to make coffee in the morning, heating up something real quick and to heat up a bottle (our first is due in Nov). I wouldn't be running the stove tops or be on for more than 5 minutes at a time anyway. I am looking for a 12volt TV and if I have to I can just use a laptop to run the blu ray and input it to the tv for better viewing and sou.d.
Click to expand...

Do not use portable generators on a boat.. search CSR - plenty of threads :) They are a hazard to you and your family. People gets their heads chopped off for even mentioning them here *G*
 
I already have a microwave.on the boat but can only use it with shore power, same as the stovetop. If I ever have to replace it I will look.for a lower wattage unit, thanks for the info.

Portable.generators are fine to usr on a boat as long as you are careful with the CO and have a functional CO detector. I am a firefighter and have access to the best equipment at significant discounts as I am the one that does our equipment maintenance and purchasing for our department. I am however looming for the simplest operating solution and I believe that to be an inverter for my needs. Simple throw of a switch, use what I need and shut it off, no fuel to carry, generator to listen to nothing to carry on and off the boat. No need to fire up a grill to boil water for coffee or the wife's tea. Although a permanent, marine generator would be the.perfect solution, I'm am not going to spend $10,000 for coffee. I'll fire up the boat and go back to land to hit up a Dunkie's before I spend that kind of money. The wife is already talking about a larger boat when we have another child so this is going to be a 5 or 6 year boat for us anyway...the late 90's early 2000 320's are looking pretty good to her.

I think the transom locker hard wired to batteries and with shore power cord is going to be the best solution for my minor electrical needs. Thanks everybody.
 
Being careful with the CO is great but there are other issues, such as proper grounding, that needs to be considered when saying a portable generator is fine. Do some searches, especially from Frank Webster. Frank broke this down very well and please do not minimize the criticism you will see here regarding the use of portable generators on a boat. As a firefighter you will understand the concern since so many deaths are caused by portable generators. I personally suffered from CO poisoning when I was 18 and could have had a worse outcome if our destination was another 20 or 30 miles farther.
 
Speaking about microwaves and amp draw. I installed a small Sunbeam m/w on my last boat, with a 2000w MSW inverter. I think the m/w was 600 or 700 watts. The inverter would not power it at all. I returned it and got a Haier brand of the same size. That one worked, and although the inverter was struggling, it worked for the three years I had the boat. So, very possibly the Sunbeam had a startup surge that the inverter couldn't handle.
 
Danny Troy said:
Speaking about microwaves and amp draw. I installed a small Sunbeam m/w on my last boat, with a 2000w MSW inverter. I think the m/w was 600 or 700 watts. The inverter would not power it at all. I returned it and got a Haier brand of the same size. That one worked, and although the inverter was struggling, it worked for the three years I had the boat. So, very possibly the Sunbeam had a startup surge that the inverter couldn't handle.
Click to expand...
The microwave probably had timing and power control circuits that required a full sine wave for clocks and counters and the modified sine wave inverter could not feed the need.... Common problem especially in AC circuitry. Appliances that have AC - DC converters to operate (DVD, Flat Screens, Cell phone chargers, etc) typically don't have such issues.
 
Don't forget about killing swimmers. You could do that too, if I understand correctly. I believe the same phenomenon that exists in marinas (Electric Shock Drowning) also exists with improperly installed generators on a boat when they are plugged in the shore power inlet. If you've never heard of this, you can read all about it here: http://www.electricshockdrowning.org/; with specific details here: http://www.electricshockdrowning.org/?page_id=1445. And in case you can't be bothered to click the links, the following picture summarizes it pretty simply (with proper credits to ESDPA):

ESDPA.jpg

You automatically have a broken ground, because there is nothing to ground your portable generator to. In addition, most portable generators have a floating neutral- they assume the neutral on the load side is used / not switched out, and precisely the opposite is done on a boat. So any shorts (line to neutral, or line to ground) will attempt to find ground through the water...and anyone around your boat in the water. I don't think GFI breakers will operate correctly either since they don't have a proper reference to measure against.

Frank or someone with more direct knowledge and experience can corroborate or correct this.
 
A concern but premis is not exactly correct. A portable generator obviously derives current within it's self consequently the hot and return wiring are independent from any other electrical path for current to flow. The ground and neutral conductors are landed on the same terminal within the generator just like a marina's main breaker panel board. The marina has grounding through all panels, dock elements and earth consequently a boat that has a marina provided power fault through it's ground or bonding system willl return current through the water and anyone in the water. So for current to flow through a body with a generator you need a means to short between both of the generator's derived legs and / or the ground and hot legs not the earth or water. It would, however be very wise to connect the generator's frame to the boat's ground and bonding system such that if the appliance you are operating has a fault the current will always find a ground path removing a person from the equation.
 
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ttmott said:
The ground and neutral conductors are landed on the same terminal within the generator just like a marina's main breaker panel board.
Click to expand...

This isn't true for most small portable generators, actually, including Honda's in general, which are very popular on swim platforms. The Honda EU2000 in particular, which is the most common one I see, connects system ground to the generator chassis but explicitly does not bond the AC neutral to the system ground. There is even a warning in the owner's manual.

What is the path to ground in the case of a short in this situation?
 
From OSHA
Bonding Versus Grounding​
Bonding and grounding are separate requirementsfor generators and other electrical distributionsystems. Grounding means the connection,or the establishment of a connection,of an electric circuit or equipment to referenceground, which includes the generator’sframe. Bonding is the intentional connectionbetween the grounded circuit conductor(neutral) and the grounding means forthe generator, which includes the generator’sframe. Thus, effective bonding of the neutralconductor to the generator’s frame is also aconcern for the safe use of the equipment. Aswith grounding terminal connections, properbonding of the neutral terminal of a powerreceptacle may be confirmed via testing by acompetent electrician with the correct equipment,and the ohmic resistance should measurenear zero and must not be intermittent,​
which indicates a loose connection.

If one should bond the ground and neutral external of the generator any GFCI would be rendered ineffectual as a measurement of current balance between the hot and neutral cannot be done and if a GFCI is installed on the generator it would continuously trip.
 
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bajturner, the path to ground is always the path with the least resistance.
 
wyrman said:
bajturner, the path to ground is always the path with the least resistance.
Click to expand...

Almost correct.
the path to ground is always the path with the least Impedance
 
So, some interesting responses here, I'll presume none meant to be sarcastic! I don't mean to be disingenuous here, and perhaps I will learn something, but I have seen this topic debated quite a bit by a number of people- some knowledgeable, some not who don't claim to be, and some who think they are but actually are not. I consider myself somewhat knowledge and continue to try and glean information, but in the meantime have done my own research to try and really understand the topic. I do know there are things I don't know.

Regardless of the semantics of bonding versus grounding, what the OSHA requirements are, or what path electricity will take for a given impedance (and for the record, electricity will take all available paths with the current along each path inversely proportional to the impedance of each path, not just the path with the least impedance), it seems the key issue is being missed.

Consider this scenario:
- A Honda EU2000 generator is plugged into the shore power inlet at the transom.
- The Honda generator neutral is not bonded to ground by design (it depends on the other end to do that and requires the transfer switch to not break the neutral), and this can quickly be verified with an Ohm meter.
- The green earth wire and neutral are separate on the boat so there is only a single bonding point on the shore when plugged into shore power. This is also by design.

Now let's say there is a short, hot to ground, either in the boat wiring or in an appliance.

Walk me through the current path. Is it not hot to ground, which electrifies the ground bus on the boat as well as the chassis of the generator, but no breaker trips because there is no return path to ground, and no reference for a GFI. Current looks for a path and finds it via grounded conductive interfaces to the water, and through the water / bodies in the water? Please correct me if I'm wrong.

The EU2000 chassis, by specification, is to be grounded with an earth ground bar when ground and neutral are not bonded on the load side. Pretty hard to do on a boat.

The neutral in this scenario is floating, not actually neutral at all, and could have dangerous voltages on it. I haven't considered the possible perils on the water of this yet...
 
You are correct regarding the Honda generator; this unit is a generator / inverter whereas the inverter creates the AC power and does have a floating ground.
Now lets break down the boats system: When the boat is tied to the shore power it's hot leg is home run to the shore circuit breaker uniquely. The neutral leg is run uniquely to the shore panel board's neutral buss which is then bonded to the ground buss so at one point and only one point the neutrals and grounds are bonded together. If the boat has a transfer switch at no time are the neutrals and grounds tied together by the transfer switch. The transfer switch simply moves both the neutral and hot conductors either to the shore system or to the boats internal generator system but never are the two systems simultaneously tied.
The boat's ground system is also bonded through all of the metallic elements including engine blocks, generator chassis ( it it has a generator) and battery neg posts. The boat's ground system also should run through galvanic isolators then to the shore connection; this is to control galvanic corrosion yet still provide a path for fault current to ground. All onboard installed generators have the neutrals and grounds bonded internally so as to create that required single point bond when the transfer switch is positioned to the generator. The above configuration is a NEC and ABYC requirement. Should you loose your boat due to intentional faulty wiring (not compliant) the insurance coverage may be at risk and / or you may be exposed from a liability standpoint by the marina or others affected.

If the neutral is floating due to the design of the generator and the generator chassis is not tied to the boat's ground plane I would submit that any fault in the system has little chance to safely be vetted to ground and the configuration is much more hazardous than a compliant configuration. At all times if this generator is tied to the boat's power system any GFCI protection will not trip in a fault condition as there is no other path for fault current to pass to imbalance the equal current between the hot and neutral that the ground fault instrument is looking for. The safest configuration if one must go down such a path is to bond the neutral and ground at the plug that connects to the generator. This plug then must be dedicated to the generator and have no other purpose. From what I understand RV's deal with the same issues using these generator invertors.
 
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either way this is done will be for very short term only. I am trying to avoid the generator on the swim platform altogether, not because i am terrified by the electrical fire i am undoubtedly going to start now after reading this thread. but because i don't want to have to drag along and fire up a generator for a couple of minutes of power. if i can just hard wire an inverter and run a cord to the shore power for a short, 5 minute max amount of time on a microwave that i already have, it would solve a lot of problems. not exactly the cheap way because a pure sine wave inverters aren't cheap. does anybody know what kind of wattage i would need for to safely handle only a microwave? i'm not sure what kind of power it draws. should i be looking for a 1500...2000 range? i'll take a look at the microwave when i get home in a few days.
 
Yup, so a 2000 watt microwave will draw about 17 amps at 120VAC. With a typical inverter efficiency of 85% you will find a battery demand of close to 200 amps at 12 VDC. With this load running for 20 minutes between battery recharge is calculated at 208 AH then double that for reserve capacity so, lets say you need 400 AH of battery capability to ensure you never draw below 10.8 volts ( critical for battery life). A typical group 27 battery is about 100 AH so 4 Group 27 batteries will be required with a 2000 watt continuously rated inverter. Cabling between the inverter and batteries will need to be a minimum of 2/O and less than 4' long. Not a cheap venture.... But that's the story.
 
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AFD said:
either way this is done will be for very short term only. I am trying to avoid the generator on the swim platform altogether, not because i am terrified by the electrical fire i am undoubtedly going to start now after reading this thread. but because i don't want to have to drag along and fire up a generator for a couple of minutes of power. if i can just hard wire an inverter and run a cord to the shore power for a short, 5 minute max amount of time on a microwave that i already have, it would solve a lot of problems. not exactly the cheap way because a pure sine wave inverters aren't cheap. does anybody know what kind of wattage i would need for to safely handle only a microwave? i'm not sure what kind of power it draws. should i be looking for a 1500...2000 range? i'll take a look at the microwave when i get home in a few days.
Click to expand...

Referring back to my previous post about the microwave size.
Check the size of the microwave, if it is 1100, then consider buying a smaller one, 700W.
You can then downsize the invertor, and the battery capacity required.
Which will be cheaper in the long run.


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