302 cross over switch

[Captain Blok]

In last weeks As the prop turns it was stated that if you use the cross over switch then you will be able to heat your hot water tank while running. Is the also true for the 302?

 

[knotflying]

Don't know your specific boat, however, a) is your hot water heater connected to your inverter circuit? b) If so, can the inverter output handle the load? c) Does your alternator put in the same or more amperage that the hot water heater consumes?
Do you have a generator? If so I would think that the water heater would be on that circuit and you can run the heater off of the generator. Your electrical configuration will dictate what you can and cannot do. A little research on your part will give you an answer for your specific boat.

 

[BB marine]

Unfortunately I was not able to listen to the Presentation "As The Prop Turns" last week and I would be interested in the reasoning behind that if it was stated that way. My opinion is the cross over switch is only used in a low battery condition of either the house or engine batteries. Examples: House battery is lower than 9.5V The engine is running and the ACR lite is off (engine battery to house batteries ACR) Turn the cross over switch on for 90 seconds the ACR will sense the voltage and close. Now the house battery is getting charged after a few minutes of charging turn the cross over switch off. Example: The start battery does not have enough CCA to start the engine (your in an anchorage) Turn the cross over switch on this combines both house batteries with engine batteries for an emergency start. Monitor engine charging once the engine is started. When you see an increase of battery voltage above 13V to 13.6V turn the cross over switch to the off position. Monitor engine battery voltage while on your way back to the harbor.

If you have an inverter on board that has a capacity greater than the hot water heater amp/watt requirements and the electrical panel is wired to have the hot water heater useable with the inverter then you should be able to heat the water with the engine running without turning on the crossover switch if properly wired ( Many are not in the Ranger /Cutwater models. I changed mine so it is. I use all electrical components " using power management" while under way with the exception of the Air condition compressor. I do use the fan for circulation.)


ACR designed functions

As long as the battery bank that has the charging source Alternator in this case reaches 13.0V 90 seconds or 13.6V for 30 seconds and the thruster battery bank is above 9.5V and the house bank is above 9.5 V all the batteries are connected together until the battery bank with the charging source falls below 12.75 10 seconds or 12.75 for 30 seconds.

Combine after 30sec 13.6 V
Combine after 90sec 13.0V
Open after 10 sec 12.35V
Open after 30 sec 12.75V
Under Voltage lockout 9.5 V
Over Voltage lockout 16.0V

So to answer your question in my opinion If the alternators from the engines are working properly and your house batteries are not below 9.5 V the house and engine batteries are essentially automatically crossed over. Now if I had compromised house batteries or house batteries that are not 80% Charged reading 12.5V with the engine running I would not turn the hot water heater on. I also would not turn my cross over switch on. When I am under way the engine battery is No 1 importance. Newer diesels and outboards have voltage requirements to run. Voltage spikes are an ECU's enemy. There are many built in electrical devises to protect voltage spikes but not having some type of isolation devise between the engine, house and thruster battery is not advised. (my opinion).

 

[ixlr8]

My foggy memory from last weeks webinar. Andrew recommended 'combining' the batteries so if high draw item, like the inverter running heater, pulled the voltage below the ACR set point, then the ACR would disconnect and not charge the battery. "Combining" them would prevent this from happening.
I also believe he said that boats that are setup to get heat from the engine, RT-29/31, the inverter is not wired to the water heater and can't be used. But my boat doesn't get heat from the engine so I didn't pay too much attention during this discussion. I believe the 302 is outboard powered so I believe the inverter can feed the water heater.
Sure will be nice when they get the manuals updated/corrected/generated for these boats.

 

[Cutwater28GG]

i had a similar question on this section of the presentation and posted in the thread for that webinar.

 

[Captain Blok]

Brian,
You can watch it here.
https://youtu.be/Uj_am-ecSt4

What did you need to do to change your wiring to have the hot water hearter draw from the inverter

 

[MarcoArias]

Hi,

This is also true for the 302. Feel free to shoot me an email if you have any more questions.

Thanks!

 

[BB marine]

Brian,
You can watch it here.
https://youtu.be/Uj_am-ecSt4

What did you need to do to change your wiring to have the hot water hearter draw from the inverter

When I installed the inverter I wired the 10/3 boat cable from inverter to the selector switch ( shore power /inverter/generator. The factory wiring from the 120ac breaker panel to the selector switch only included the single side of the breaker panel, outlets and microwave. I had to install an additional wire from the selector switch to the breaker panel to power the other side of the panel .Now all circuits can be operated off the inverter. I use the electric stove, and marine air unit for circulating air in the pilot house. I can use the hot water heater but I never have because the engine coolant heats the exchanger in the tank while under way.

Thank you for sending me the link. I watched the presentation it was very good and informative. I do have to disagree with the cross over switch analogy. Possibly a misunderstanding of how the ACR function. Here is a explanation from Blue Sea

An ACR senses when the voltage of either of the batteries rises to a level indicating that a charge source is active (13.0V for 90 seconds). The ACR′s contacts then connect and the ACR applies the charge to both batteries. If the voltage on both of the batteries subsequently drops to 12.75V for 30 seconds, the ACR will disconnect, isolating the batteries. An ACR does not direct the charge to the battery that “needs it the most” or has the lowest terminal voltage. If there is a charge present on either battery, indicated by a high enough voltage, the ACR will combine the batteries.

 

[Captain Blok]

So my middle and right circuit panels are not hooked up to the inverter. I pulled the panels out to look at the back. The left side is independent of the middle and right with are joined with a buss bar. There are 2 inverter output lines, one to the left, and one to the middle that is joined to the right side. But the middle and right are getting no juice from the inverter and that is what the hot water and BBQ are on. My next guess is that one of the leads is disconnected at the inverter. I was going to look there but it is hard to get at. My feeling is that it was disconnected because people were having trouble draining their batteries down by using the electric BBQ. Just a hunch.
I want to reconnect it. I don't use the BBQ and have removed it and use a LP one instead. But I do want to heat up hot water when I am running.
the 302 has twin 300 OB so there is no engine heat for hot water. But the 2 300s should be ample to keep up with it for an hour of hot water heating according to their spreadsheet.

 

[BB marine]

From what I am understood from the presentation As The Prop Turns the larger outboard models with twin outboard motors the factory has wired the breaker panels to allow the water heater to be used ( two alternators higher amp output capacity) when using the inverter. If your inverter is on and you have circuits that have 120V power but the water heaters no power, I would assume the panel was not wired to power the water heater. ( by intension or mistake) I believe the panels used by Fluid Motion are custom made to their specifications by Blue Sea. When I installed my inverter the Blue Sea rotary switch (off/shore power/inverter/generator) was wired to the breaker panel. When I installed the Kisae inverter has per instructions I also used the Blue Sea wire schematic and instructions for wire placement to the rotary switch. ( proper wiring is very important you must make sure that the neutral/ground from the inverter is disconnected and isolated when using shore power or generator) When I powered up the inverter all worked well except I had power only to one side of the panel using the inverter. The panel was wired this way. I had to install an addition lead to cross over to the other side of the panel as I previously stated. When this was done the complete breaker panel was powered thru the inverter. Kisea inverters have over load protection and will shut down if high load is detected. You should still use power management! I would advise contacting customer service Cutwater if you are troubleshooting this yourself to get a schematic that shows the exact wiring of the panel for the Cutwater 302 or hire a ABYC certified electrician to trouble shoot the issue of no power going to your water heater while using the inverter. If your 302 Cutwater is wired to have a water heater used with an inverter. Based on Marco's comment it is.

 

[Captain Blok]

The 302 is not wired to use the hot-water heat with the inverter and also the BBQ is not which I removed anyway because it was worthless to me. I am rarely at a dock with shore power. When in the water she lives on a can when not in use.
I confirmed this with Marco. I want this rewired as other models are, otherwise I can't get hot-water. I do have a Yamaha generator that will do the trick by plugging the shore power cord into it (it's just barely enough power), but it's a drag to pull into a nice quiet spot and then turn on the portable gen for an hour or so and make a bunch of noise for others to hear if not alone. (I don't want to be that guy). Plus it doesn't stow anywhere and I have to leave it on the deck. I am told that if it is rewired that it voids the warrenty which doest seem right since other Cutwater single OB models have it wired right (as stated by Andrew C. in the Power Management video) and the 302 is a twin with twice the power output.)

If I knew this ahead of time I would have demanded it changed before we took ownership. She's still a great boat, the 1st mate loves her, and I am not given her back. 😀

Hot water :cry:
BBQ :cry:

 

[BB marine]

Warranty ? What Warranty? What is the watt output ( continuous max output )? What is the max watt needed to operate the hot water heater ? I do not know what the factory installed inverter capacity is on a 302 but I would assume a boat that size would have an inverter with at least a capacity of 2000 W continuous operation with a momentary surge of 4000W. Actually because of the house battery bank size (400 ah +) a 3000W would be more appropriate. I have a Kisea 2000W inverter. It is rated for 2000W output use or 16.6 amps. When looking at the user chart in the manual it shows battery capacity needed for 2000W AC draw and using the 2000W capacity and no where does it say Voids the warranty. It has over load protection in the event of over capacity draws. I have my complete panel wired to the inverter. This configuration requires no complacency and power management is very important ( I have an inboard and do not require the inverter for the hot water heat, but I do need to use it for the stove). An average marine hot water heater power demands are between 750W to 1500W. I would assume that a manufacture building an outboard powered vessel with the amenities in a R23, R25, R27, C24 and C302 would install a hot water heater rated at 750W so as to be able to power the heater with an inverter with a comfort margin. Even if the manufacture installed a 1500W heater it should not void a warranty because the demand is below the designed output of the inverter. Does the warranty void if you use a coffee maker plugged into an outlet and the Microwave ? A boat with a 400 AH battery bank powering a 1500W hot water heater would have enough capacity to operate the hot water heater continuously, comfortably for an hour before needing to charge the bank. I would not advise doing that. But a boat with a 400 AH battery bank with two alternators with 50amp charging capacity heating water using an 2000W inverter with the combined battery capacity and charging capacity. I really do not see what the issue is and why that would void a warranty. I personally would call an ABYC certified electrician have him/her look at the power panel, advise and configure the inverter / hot water heater if it is feasible in his /her opinion. If so wire it according to ABYC specifications. Honestly I would have thought the factory representative would have advised you to do the same.

 

[iggy]

If you look at the excel sheet, the hot water heater uses 750 Watts using 67 DC amps for one hour. Now add in any thing else that is on. I don't know if I would use the inverter to run the hot water. As mentioned it could be wired to do so.

Two many venerables to say one should or should not heat off the inverter. Can you heat off the engine, do you have a genset, what other power is needed at the time, are you underway recharging your batteries?? I am sure there is more!

Personally, I would rather run the genset then to pull that kind of power from the batteries. Going ashore and leaving the fridge on is going to do enough to shorten the batteries life. Which goes back to, the boat was not wired to do that.

 

[Captain Blok]

Yeah we have the 2000 as well. Water heater 750 w. 2 Yamaha OB 300s cranking 70a each at cruise. I would just be putting it on for an hour or so on a multiple hour trip. I have used the power management spreed sheet and we have plenty of juice.
I have been instructed on how to rewire and it looks pretty straight forward. The space is a little tight to get to the connections but doable. My only hesitation is the warranty thing. I want FM to agree to let me do this and not void anything. Better would be for them to pay for it to be as it should have been in the first place. One of the problems for that is that we are pretty remote so if I want it done its more practical for me to do it.

 

[Danation]

How old is your boat? Beyond the motors, isn't it just a one year warranty?

The electrical setup is more than capable of handling the power load while underway. I think the reason it is wired the way it is to keep you safe from yourself and eliminate customer service problems. You need to understand power usage. All it takes is one time to anchor up and forget your hot water tank is on and the next thing you have is dead batteries. If your willing to take that risk, you should fine. I'll be looking to make the modification to mine. I can't see going on trips for weeks at a time without having hot water available.

Yeah we have the 2000 as well. Water heater 750 w. 2 Yamaha OB 300s cranking 70a each at cruise. I would just be putting it on for an hour or so on a multiple hour trip. I have used the power management spreed sheet and we have plenty of juice.
I have been instructed on how to rewire and it looks pretty straight forward. The space is a little tight to get to the connections but doable. My only hesitation is the warranty thing. I want FM to agree to let me do this and not void anything. Better would be for them to pay for it to be as it should have been in the first place. One of the problems for that is that we are pretty remote so if I want it done its more practical for me to do it.

 

[Captain Blok]

Yeah your right it is only a year and mines a 2018.
I was just talking to Andrew C. and he said its an easy switch. Jumper hot wire from the inverter side of panel to hot side of the shore power panel. Then Jumper between the Inverter neutral line bus to the Shore line buss.