Induction Cooking -- Tips?

[Dockhead]

Originally Posted by Auspicious

. . .Units matter. Kilowatt-hours are a unit. kW/hr are not.

Yep, you're right. My sloppiness.

Originally Posted by Auspicious

.. . . Check insurance statistics. Both afloat and ashore there is more fire damage from electrical installations than gas. Induction is NOT safety. In point of fact there is more maintenance and inspection to be safe and dealing with a failure is more difficult.

I have to disagree with you there. The argument is fallacious -- removing gas and adding induction does NOT indeed mean you are adding a new risk. You already have the electrical system. If you stick with gas, you are not reducing the electrical risk. You still have the same risk -- you use electrical power for other things.

Originally Posted by Auspicious

Gas:
"The electrical system went tango-uniform. How do I cook?"
"Hang on, I have a male-male nipple to jump around the gas solenoid."


"The gas solenoid rusted shut."
"Hang on, I have a male-male nipple to jump around the gas solenoid."


Electric:
"The electrical system went tango-uniform. How do I cook?"
"You don't."
"What about all this raw chicken?"
"We're buggered."

The whole electrical system went T-U? C'mon . . . how many times has that ever happened to you or anyone you know? And if the entire electrical system is T-U, you've got much bigger problems than raw chicken.

Originally Posted by Auspicious

"Skipper, there is smoke coming from under that berth. Aren't the batteries under there?"

"We're buggered."

Right, and if we had only been smart enough to leave the gas system in place and not go to induction, then we wouldn't have any batteries, and no electrical fire . . . . Is that what you're saying?



You are missing the systems architecture advantage of switching to induction. You completely eliminated one troublesome and dangerous system, without replacing it with a new troublesome and dangerous system -- because you already have that system.

So the resources saved can go into making that one system more reliable and safer. It's a lot easier to do that with on system, than with two. Spend the time you used to spend leak testing the gas system, humping gas bottles, replacing (or jumping around) rusted solenoids -- keeping the electrical system safe (and with me, you now know two people who tighten wire junctions and check wire temperatures). This is good systems architecture.



With so many things on my boat powered by electricity, I have concentrated a lot of effort into backups and failsafes in that system. I have a 2.5kW heavy duty school bus alternator on the main engine plus a 6.5kW heavy duty low speed generator, spare charger, spare inverter, etc. etc. etc. Spare school bus alternator, spare belts, diodes, brushes, etc. Large inventory of spares for the generator, including spare starter, injectors, injector lines, fresh and raw water pumps, etc etc etc etc . In a decade of cruising on this boat, sometimes in very remote places, I've had this or that thing in the electrical system fail, but I've never been dark, and never been unable to keep the power flowing.

[Auspicious]

Originally Posted by Dockhead

removing gas and adding induction does NOT indeed mean you are adding a new risk.

It does. Induction fed by an inverter is the only sustained high current draw system on the boat. Windlass and winches are intermittent.

Originally Posted by Dockhead

The whole electrical system went T-U?

Several times. I've had MPPT controllers fail. Newer boats with individual controllers are more robust, but you can get to the point where you can't put the energy back in. Lots of failed generators. Failed alternators. None are a big deal for coastal cruising. On passage, big deal.



The point about raw chicken is the issue of failure cascades where one failure leads to another. An inconvenience becomes a crisis.

Originally Posted by Dockhead

Right, and if we had only been smart enough to leave the gas system in place and not go to induction, then we wouldn't have any batteries, and no electrical fire . . . . Is that what you're saying?

No. What other sustained draw do you have? I'll return to the cig lighter power point analogy. 30A for 20 seconds is fine. Sustained draw for cig plugs is only 6A (a BMW power plug is better, Anderson plugs better yet).

Originally Posted by Dockhead

because you already have that system.

Not sized correctly.

Originally Posted by Dockhead

With so many things on my boat powered by electricity

Which is the attitude that leads to boat failures. Have you increased your wire sizes for higher current draw over longer periods of time? All the stuff I listed above: temperature, connections, etc.

[StuM]

Originally Posted by Auspicious

It does. Induction fed by an inverter is the only sustained high current draw system on the boat. Windlass and winches are intermittent.

Apart from the:
Aircon
Microwave
Toaster
Electric kettle
Multipot
Rice cooker
to name a few which draw similar to the induction plate.

[Montanan]

Induction cooking appliances operate with much higher efficiency than other cooking appliances and with simple appropriate wiring from an inverter should not have any significant I2R losses due to conduction.

Reference: https://cooktophunter.com/voltage-requirements/


"Voltage Requirements

Each cooktop may require a different voltage to function and every country has a different voltage distribution. However, most of the countries today follow the most common standard of 230 V ±10% at 50 Hz. Most of the European countries as well as many other regions have made 230 V their standard voltage distribution. But there are few countries like the United States, Canada, Japan, etc. that use 100-120 V as the standard voltage.

Almost all induction cooktops today are made to be compatible with the common standard voltage supply. Most of the cooktops would be rated 120 V or between 200-240 V, which implies they will function in almost any countries. Even though the voltage supply in the United States is 120 V, they can still use a cooktop rated 230 V by making use of ‘three wire – split phase’ wiring that can produce higher voltage.

One thing you should not forget is the required circuit. Almost all portable induction cooktop with single burner has a wattage between 1200-1800 W. This means that if you use a single burner induction cooktop, the required minimum circuit would be 15 amps. The bigger the cooktop or the cooktop that supports multi burners will require higher amps circuit. Normally a cooktop with 4-5 burners has a minimum circuit requirement of 40 – 50 amps.

Power Consumption/Energy Efficiency

Induction cooktops are known for their energy efficiency and heat consistency. In induction cooking, the heat is generated from the cookware itself and thus no heat is lost. Top notch induction cooktops have special features called the ‘SpeedBoost’ that enhance the cooking speed thus cooking food twice faster than conventional cooking. The US Department of Energy states that the energy efficiency of induction cooktop is as high as 84%, compared to other non induction electric cooktop with 74% and gas cooktop with 44%."

[Montanan]

Originally Posted by StuM

Apart from the:
Aircon
Microwave
Toaster
Electric kettle
Multipot
Rice cooker
to name a few which draw similar to the induction plate.

So true.

One just likely needs to remain highly cognizant of avoiding a cumulative excessive load. With induction cooking the A/C load is lessened due to the lack of heat emissions from burners and lowered humidity also due to not combusting.

It could push the inverter to the max or to a tripping point to have four induction heating elements, the electric hot water heater, the A/C, the electric kettle, microwave, toaster, autopilot,, refrigerator / freezer / icemaker, electric oven, radar, all on at the same moment.

The beauty of utilizing higher voltage systems onboard avoids the issue with dealing with low voltage / high amperage DC systems.

[Dockhead]

Originally Posted by Auspicious

. . ..Which is the attitude that leads to boat failures. Have you increased your wire sizes for higher current draw over longer periods of time? All the stuff I listed above: temperature, connections, etc.

What "higher current draw"? Weird. I have a 12 amp ring main socket circuit, which powers the induction hob, besides electric heat when I use it, and anything else stuck in sockets. 12 amps was enough for everything else, and it's enough for this.



No load has been increased or indeed harmed in the process of making this movie. It's engineered for 12 amps, and if I exceed it, the breaker pops. If the breaker doesn't pop, the circuit is designed to be happy with the load until the cows come home.


And yes, I've tightened the connections, and used a laser thermometer to verify that there aren't any bum connections, and do that periodically.

[Auspicious]

Originally Posted by StuM

Apart from the:
Aircon
Microwave
Toaster
Electric kettle
Multipot
Rice cooker
to name a few which draw similar to the induction plate.

Most people don't run aircon off an inverter, certainly not the 8k - 20k BTU units most common. Water heaters are generally not run off inverters either. Multi-pots (horrible devices but that is a different matter) and rice cookers are not particularly high-current sustained loads. Microwaves, toasters, and kettles are intermittent loads. Also intermittent are things like coffee makers and engine starters.


That isn't to say that intermittent high-draw loads don't come with their own requirements. Sustained high-draw loads are major stressors to a low voltage electrical system.



It's an entirely different matter if you are on a boat that starts the generator before dropping lines and runs it (or them) continuously until lines go ashore. For them current is an order of magnitude lower and heat (I-squared-R) two orders of magnitude lower.

[Pelagic]

Originally Posted by Auspicious

Several times. I've had MPPT controllers fail. Newer boats with individual controllers are more robust, but you can get to the point where you can't put the energy back in. Lots of failed generators. Failed alternators. None are a big deal for coastal cruising. On passage, big deal.



The point about raw chicken is the issue of failure cascades where one failure leads to another. An inconvenience becomes a crisis.


No. What other sustained draw do you have? I'll return to the cig lighter power point analogy. 30A for 20 seconds is fine. Sustained draw for cig plugs is only 6A (a BMW power plug is better, Anderson plugs better yet).


[/B][/I]

Not sized correctly.




Which is the attitude that leads to boat failures. Have you increased your wire sizes for higher current draw over longer periods of time? All the stuff I listed above: temperature, connections, etc.

Hi Auspicious
To support your argument....
...You assume that :
1....we have not sized and installed the high voltage system properly.

2....that we are incapable of maintaining and monitoring for any problems with said system.

3...that we have never considered backups like generators, large case alrenators or even a standby 2nd invertor .

4....that we spend all our time on passages, carry no critical spares and are incapable of making repairs underway.

My point is that you are making self-fulfilling negative arguments, sometimes relying on semamtics
........rather than contributing to the discussion on Induction Cooker Tips.

But that's ok....each to their own[emoji111]

[Auspicious]

Originally Posted by Dockhead

What "higher current draw"? Weird. I have a 12 amp ring main socket circuit, which powers the induction hob, besides electric heat when I use it, and anything else stuck in sockets. 12 amps was enough for everything else, and it's enough for this.

It's the bit between the batteries and the inverter that is of concern. You have a 220V/50Hz boat, correct? If you're feeding your inverter from a 12VDC battery bank you are drawing over 230A between batteries and inverter. Sustained over a substantial period of time (say for stuffed roast pork loin) THAT is a sustained high current draw. Those are the circuits that should have all connections checked for tightness and corrosion on a regular basis and wires that should be checked for temperature (a handheld IR thermometer is key).



Wire size guides implicitly assume short intermittent loads at those current levels (windlass, power winch, thrusters). Wire sizes, installation shortfalls, and connections (again loosening from thermal cycling and vibration as well as corrosion) are the things to worry about. Those are why you can't be happy until the cows come home.


For you in particular Dockhead (and Pelagic as well) whose posts I stop to read I'm pleased that you monitor temperature. I would be sad if you or your boats became casualties.


The numbers are clear. The science is clear. The engineering is clear. The insurance statistics show that there aren't any fundamental conceptual errors. I'm not saying you can't cook on induction at sea (I wouldn't, but that goes to FMEA), I'm saying that 1. it isn't safer and 2. there are implications that aren't addressed by CE or ABYC.

[CatNewBee]

Originally Posted by Auspicious

It does. Induction fed by an inverter is the only sustained high current draw system on the boat. Windlass and winches are intermittent.






Several times. I've had MPPT controllers fail. Newer boats with individual controllers are more robust, but you can get to the point where you can't put the energy back in. Lots of failed generators. Failed alternators. None are a big deal for coastal cruising. On passage, big deal.



The point about raw chicken is the issue of failure cascades where one failure leads to another. An inconvenience becomes a crisis.





No. What other sustained draw do you have? I'll return to the cig lighter power point analogy. 30A for 20 seconds is fine. Sustained draw for cig plugs is only 6A (a BMW power plug is better, Anderson plugs better yet).


[/B][/I]

Not sized correctly.





Which is the attitude that leads to boat failures. Have you increased your wire sizes for higher current draw over longer periods of time? All the stuff I listed above: temperature, connections, etc.

The highest continous AC load on board are in fact the A/C units, we have 4 on board with 42000btu in total, they suck up 6kW when running, also a hot water boiler with 1800W, factory installed and a watermaker running either on AC or DC. You can run all 4 A/C units only when the generator is on, on inverter you can run only half of them and they burn more power than the 4 burner induction hob. While cooking, you not run all 4 plates on power boost at the same time (7kW), usually you heat up the pot and then turn down to simmering, 3 burner simmering in parallel draw about 2kW, like a hair dryer. They pulse, and do so in sequence to keep the load as low as possible on the line.

I agree, if you never have used an induction hob, you have no idea what you are writing about.

Current does not spill out of the sockets, nor do wires leak current in contrast to propane connections, hoses and appliances. Electric circuits are safer and easier to fix than gas installations.

The DC high current paths are short and if well dessigned, there will be no issues whatsoever. Granted, inverters can fail as any other system can, but can be replaced if necessary easily, they even can be redundant with the right gear.

Induction hobs are so much better than propane, cool and plain surface, easy to operate, easy to clean, instantly on and off.

Sushi chicken? No, there is a oven too, where you can roast it, a bbq to grill it, an instapot to boil it.

Inverter failure? Run the generator.

How about your chicken sushi when you run out of propane and nobody is willing to refill your foreigh bottle?

And if you have a propane leakage, the sushi is your least problem.

[Montanan]

Originally Posted by Auspicious

Most people don't run aircon off an inverter, certainly not the 8k - 20k BTU units most common. Water heaters are generally not run off inverters either. Multi-pots (horrible devices but that is a different matter) and rice cookers are not particularly high-current sustained loads. Microwaves, toasters, and kettles are intermittent loads. Also intermittent are things like coffee makers and engine starters.


That isn't to say that intermittent high-draw loads don't come with their own requirements. Sustained high-draw loads are major stressors to a low voltage electrical system.



It's an entirely different matter if you are on a boat that starts the generator before dropping lines and runs it (or them) continuously until lines go ashore. For them current is an order of magnitude lower and heat (I-squared-R) two orders of magnitude lower.

Not wishing to drift from the distinct subject of induction cooking, but such devices greatly reduce the peak A/C loading as to both humidity climate control and heat transference required from the exhaust of propane gas combustion in the galley, thus there is the prospect of a significant offset in power consumption.

The self contained marine cooling and heating climate control units do not require large inverter capacities. By way of example, MarinAire's 16,000 BTU cooling, 17,000 BTU heating capacity self contained units, utilize a maximum of 1,480 watts. At 110-120V/50-60Hz, the running amperage is 10.8 and the brief starting current is 17.6 and at 208-230V/50-60Hz, the running current is 5.5 and the starting current is 11.

A two burner induction cooking unit would draw about twice the power of the A/C, easily supplied by a moderate genny and / or smoothed by a battery bank. Since induction cooking can be derived quickly one can simply turn off the AC unit for the brief spell of cooking and because the cooking is not producing hot exhaust from burning propane the galley will not become stifling hot and in need of a high powered AC unit to keep the cook cool and sociable.

[Auspicious]

Originally Posted by Pelagic

1....we have not sized and installed the high voltage system properly.

2....that we are incapable of maintaining and monitoring for any problems with said system.

3...that we have never considered backups like generators, large case alrenators or even a standby 2nd invertor .

4....that we spend all our time on passages, carry no critical spares and are incapable of making repairs underway.

My point is that you are making self-fulfilling negative arguments, sometimes relying on semamtics
........rather than contributing to the discussion on Induction Cooker Tips.

But that's ok....each to their own

Jeepers. It's a good thing we have a time zone difference. I go to bed at US ET 2030. Y'all could outlast me.


1. I'm not worried about the high voltage side. As noted if you run generators from port to port this is normal, usual stuff and CE standards are fine (wire size, chafe protection, material selection (this was a real hassle in the US for a while until UL caught up), etc.). It's the low voltage side between batteries and inverter that concerns me.



2. As described, your background like mine predispose you to a level of care that is not common in the recreational boating community. I expect that like me you have a list of "every time," "monthly," "quarterly," and other periodicity inspections and maintenance. Walk up and down the pontoons and see how many boats have had their 12V or 24V DC connections checked, cleaned, and torqued since forever. Go ahead. I'll wait. *grin*


3. I don't doubt that in your case. Shall I send you back out onto the pontoons? *grin* As I noted a moment ago, the high voltage side is a lesser concern (although based on some of the clean-up work I have done not all installations meet expectations - there are reasons you did your own rewire, aren't there?).



4. Fair enough. I don't however see infrastructure repair and maintenance before passages very often (beyond engine maintenance). Since I do a lot of delivery work I do tend to focus on passagemaking. On the other hand the catastrophic failures of high draw electrical systems are if anything more common in coastal and local applications.

[Montanan]

Auspicious you have identified the primary concern and weakness of many marine battery systems. The 12 / 24 Volt constraint which makes for comparatively poor efficiency of power conversion from higher voltage power supply sources down to the low DC charging voltage and then voltage boosts to provide AC loads and likewise as to conduction losses, cabling sizes and connector sizes and qualities as to maintaining low resistance of such high amperage schemes.

I'm fine with higher voltage, never much like high amperage.

Whereas higher voltage systems [110-120V/50-60Hz or 208-230V/50-60Hz, or even the typical 450 volt, 60Hz US Navy specs] avail much more efficient marine systems which system components are generally adapted from much less expensive and much more readily available terrestrial sector applications.

Inverters like to have voltage matching, Vin near to Vout, they become difficult to engineer and more expensive when Vin is 1/8th or 1/20th of the Vout.

In our company's, EV drive sector the circuits utilize 650 volt or now more and more 1,200 volt components, yet we still have legacy call outs for 12V DC accessory applications [e.g., HVAC blowers, and actuators which low voltage schemes are truly miserable to have to contend with ].

[Pelagic]

Originally Posted by Auspicious

.... Since I do a lot of delivery work I do tend to focus on passagemaking. On the other hand the catastrophic failures of high draw electrical systems are if anything more common in coastal and local applications.

I can understand the KISS principle on deliveries.... When I did them in the 80's the fresh water pressure breaker was turned off.

I guess my dislike for propane is a result of twice witnessing gas explosions and deaths on other boats at anchor.
Gas is such a nefarious killer, small leak after someone is rummaging thru a locker and damages the line.
On/Off tank solenoid hides that slow leak until one night after a late supper and a few drinks, the solenoid is left on.

For me, it was the stuff of nightmares, whereas electrical resistance and load is constantly mesureable and each item is monitored and breakered independently for load abnormalities

[Steve_C]

Originally Posted by Pelagic

I can understand the KISS principle on deliveries.... When I did them in the 80's the fresh water pressure breaker was turned off.

I guess my dislike for propane is a result of twice witnessing gas explosions and deaths on other boats at anchor.
Gas is such a nefarious killer, small leak after someone is rummaging thru a locker and damages the line.
On/Off tank solenoid hides that slow leak until one night after a late supper and a few drinks, the solenoid is left on.

For me, it was the stuff of nightmares, whereas electrical resistance and load is constantly mesureable and each item is monitored and breakered independently for load abnormalities

I live out in the country somewhat and have propane in my home. Its a large 250 gallon tank sitting far away from the house. I use it only for the cooktop, fireplace and grill. I have a solenoid on it connected to a timer. At any given location you have to choose a time in order to operate the solenoid and after a pre-set time it shuts off the flow. I do this not only for safety but also to insure no one can forget to turn of the grill and let it run for days. IF i were to have it on my boat I would use a similar timer.