600 Watt Inverter

[Fred]

A 600 Watt inverter came with the boat (H33.5) but was not wired up. With wiring and associated components it will cost me about $200 CDN to install. I'm questioning what I would even use it for. What do others use their inverter for. I have two AGM (100 Ahr each) house batteries and 200 Watt solar to charge them.

 

[Don S/V ILLusion]

I'm questioning what I would even use it for.

any 120VAC appliance which draws less than 600w.
Light, computer charger, phone charger, small TV, etc…

 

[TimFromLI]

$200 to install? 600 watts is not much for that kind of money. A cigarette lighter plug in type would cost less and would satisfy most needs unless you want to make coffee or run power tools.

 

[Johnb]

If it’s a good quality pure sine wave output it may well be worth installing because of its high efficiency and absence of propensity to damage your appliances. In addition to Don’s other items add electric toothbrush and razor etc that you may leave on charge for many hours.

$200 is not that much for the skilled labor to do it properly. It will draw 50 + amps on the 12 volt side and that must be wired and protected. Then there’s issues such as grounding on the AC side. Someone has to figure all that out and then do the work.

 

[Fred]

I would do the installation work myself. Its a Samlex 4-Pure Sine Wave. - most portable devices can now be charged by USB. I've installed several of those in the boat. I can charge my laptop (or electric tooth brush) with a small 75W plug-in inverter. I think that I'll hold off on the installation until I identify a pressing requirement. Plenty of other boat projects for now.

 

[Hayden Watson]

I am trying to figure out how you get to $200. Do you have a parts list?

 

[Benny17441]

What do I use the inverter for? 1) watch TV underway or on the hook (120V Tvs are cheaper, larger and better than the 12V jobs) 2) run the blender for Margaritas, 3) Use of power tools 4) Use of a small microwave oven to heat up something 5) charge phones, tablets and laptops, 6) had a 1200 Watt unit and used it to run a refrigerator for 5-6 hours. 7) ran a box fan in the cockpit when the wind dies and the air became hot and heavy. A 600W inverter need to be fused and hardwired to the batteries, no 12V sockets and plugs. It needs to be placed as close to the batteries as possible and in a well ventilated area. Many in that class offer 2 or 3 15A sockets so you can use extension cords instead of hard wiring to the boat's 120V distribution panel. You could install such a unit for around $30. Two 18 inch gauge #6 automotive battery cables, one fuse holder and fuse. Would not do without an inverter.

 

[Fred]

My estimate was based on 2 x #2AWG x 6ft cable @$4.36/ft = $52; 150A (Blue Sea) circuit breaker/switch = $97; crimp terminations etc. Alternatively I considered battery terminal mounted fuse holder and fuses but they add up as well. (All Canadian Dollars)

 

[Benny17441]

#2AWG cables is an overkill unless you plan to place the inverter at the bow of the boat and batteries at the stern. You do not need a resettable circuit breaker, you can pick a 100A fuse holder and fuse for about $10. #6AWG is all you need if you place the inverter close to batteries. It is to be understood that the inverter will be monitored and turned Off after every use.

 

[Hayden Watson]

For a 600w invertor you draw would only be 62A max at 80% efficiency so 6 gauge would work for up to 20' (40' round trip) at 10% drop. The max ampacity rating for 6AWG is 74-Amps or greater depending on the insulation temp rating so a 70 amp fuse would be appropriate.

 

[Fred]

I was going by the manufacturer (SAMLEX) instructions which indicates AWG#2 for separation distances up to six feet and a 125A (ANN125) rating for the battery fuse. I would agree that they likely err on the conservative side.

The 6' separation was based on the location that the PO pre-installed the unit however I will see if I can locate it closer to the battery if I proceed in which case the manufacturer allows for AWG#4 (distance up to 4 foot). Also, I am debating if I should run the inverter negative wire to the ground wire shunt for my battery monitor or directly connect to the battery negative (less connections). I'm leaning toward the latter as inverter use would likely be minimal.

 

[Hayden Watson]

I was going by the manufacturer (SAMLEX) instructions which indicates AWG#2 for separation distances up to six feet and a 125A (ANN125) rating for the battery fuse. I would agree that they likely err on the conservative side.

The 6' separation was based on the location that the PO pre-installed the unit however I will see if I can locate it closer to the battery if I proceed in which case the manufacturer allows for AWG#4 (distance up to 4 foot). Also, I am debating if I should run the inverter negative wire to the ground wire shunt for my battery monitor or directly connect to the battery negative (less connections). I'm leaning toward the latter as inverter use would likely be minimal.

Here is the page I found for the Samlex PST-600-12. It indicates 6AWG to 3' round trip total and an 80A fuse.
I would not connect the negative directly to the battery if you have a battery monitor. If you bypass the shunt, you will have no indications as to how much it has taken out and that would cause a significant error. If the wire that connects your negative buss is larger size than the conductor to the inverter, you would not need to include that length in your wire gage calc.
Because of their potential to draw high current, it is best to place it as close to the battery as possible.

 

[Johnb]

if I was doing that installation I would use wire and fuses commensurate with supporting a future larger inverter. The added cost would be minimal.

By the way 10% voltage drop is not acceptable in a 12 volt system. The standard is 3% and I design for half that.

I would also go for breaker. Gives you a place to kill the inverter dead when you want it off.

 

[nightowle]

The only thing we use our inverter for is a toaster when on the hook. Away from the dock, we don't need to watch TV. Everything else can be charged via 12v.

 

[sailme88]

any 120VAC appliance which draws less than 600w.
Light, computer charger, phone charger, small TV, etc…

All of the items listed can be run directly from 12v... why waste energy inverting to AC?

 

[sailme88]

600w..meh...sell it and get an inverter worth having... 1500-2000w