Beware: Furuno 1815 Radar Power Hog When Off

[bbalan]

Hi All,
I bought a Furuno 1815 Radar this past year because I like stand-alone radars and it had received some good reviews. I didn't realize that even when the unit is off it is drawing .75 amps. All the time. The problem for us is that we are full-time bluewater sailors and one of the most important uses of our radar is identifying squalls at night when passage-making. We usually turn the radar on once every hour to check our surroundings. However, the radar's breaker is below decks. It's incredibly inconvenient to constantly go down to turn the breaker on and off -- especially in inclement weather. Of course it inevitably gets left on sometimes. .75 amp is 18 amp hours / day -- a good size chuck of our daily power since we rely on solar.


Unfortunately, given our installation and boat layout, it would require a huge amount of time and effort to reroute cables and install a breaker above decks.



There are many good things about the radar (though it is not a very intuitive system) but this is absolutely a deal breaker for us. After spending thousands to purchase and install, we'll have to figure out something else... though changing radar in French Polynesia will not be easy or cheap.


Make sure you take into account this aspect of the unit before you purchase.


Fair winds,
Bruce
s/v Migration

[a64pilot]

I think it’s common, as in maybe all Magnetron Radar’s require power to keep the Magnetron warm, I think that if removed often it may shorten the life of the Magnetron.
Of course I’ve been wrong before, but I think it’s something that your going to have to learn to live with.

Some however have a “standby” which I think means that the Magnetron is kept heated, and some may have an “off” which removes all power, but a long time, up to 30 min. may be needed for the Magnetron to fully warmed up for best operation. Not saying or wouldn’t see squalls, but being fully warmed up is important for tweaking best performance from a Magnetron Radar.

Sorry, but you have my memory going back quite a lot time to an old JRC Radar we had, that at the time was considered to be very good.

For your use, something like B&G’s 4G Radar or other solid state Radar might be better.

[Mirage35]

I hadn't thought about it in the sailing context, but it's an issue with most modern electronics - dealt with it when I was doing work related to building management.

Most commercial electronics - noting again that I haven't specifically looked at marine systems - have a "standby" mode rather than the good old "off" mode some of us remember. In standby they draw power, enough that in certain circumstances (university residences are the one I remember) they can place a significant load on power systems.

So, yeah, we need to start reading specs on our marine electronics to see what the current draw is when we think we've turned them off.

[Paul L]

Certainly inconvenient that they don't offer a full off along with the standby power. Gotta give them credit for making it clear in the manual

Note: The display unit supplies “standby power” to the antenna unit when the display
unit is turned off. If use of the radar is not required for an extended period, shut off the
radar at the breaker. The antenna unit’s current consumption with the display unit
turned off is 0.8A for 12 VDC and 0.4A for 24 VDC.

[Mal Reynolds]

Why don't you just wire an on-off switch to the cockpit?



You did do that for your running, deck and steaming lights also so you don't have to run below?

[S/V Alchemy]

More "be aware" than "beware". I have the 1835 radar, with which we are very pleased, and it's the same deal. But I knew that going it, as it's a traditional pulse radar and they need to kept energized if you want them to pop into action. I turn it off at the breaker, which is located at the helm in my case, in our pilothouse.

[bongo]

I too have a Furuno Radar/GPS and am happy with it. When I first got it I was using the integral Anchor tool, to monitor our position and alarm if we were dragging anchor. The house battery was discharged by morning. I now use the Drag Queen app on my iPad instead, and open the circuit breaker to the Furuno overnight. No more issues.

[Siberian Sea]

I have a Furuno radar too. Mine is on its own breaker that I shut off when it’s not being used, matter fact all my electronics are on their own breakers in the off position.

[Moontide]

I have an older Furuno (20 years?) but issue is dierffnet on mine. With Power Off there is no draw, but in Standby it is almost the same as full on. Takes 90 seconds to warm up from a cold start so not a problem.



Can think of two options that might be doable in French Polynesia.



1.Putting a relay in the 12 volt line to the radar. Presume it would be much easier to run a small relay wire to the cockpit than the main power line since it can be much smaller wire.



Basically the same concept as on my Yanmar. Uses a relay on the starter solenoid energizing line to a relay on the engine then small wire to helm.


Seem to go through one every year or two and got tired of starting the engine via the screwdriver jumping method. Quit buying Yanmar and went online. I think the last ones were $1 each, and are lasting as long as the Yanmar ones.





Option 2 Use a windlass relay ($20 on line) and a wireless control for it (another $10 or 20). Might be even cheaper relays available since the windlass uses so many more amps than the radar.



As far as getting it there, bet there are some Puddle Jumpers who will have friends flying down that could bring them. Pretty sure you know Andy Turpin and I'll bet he knows someone flying down.



Bill

[Mike Banks]

I think you need additional power--such as a wind vane or extra solar panel or two. There is no other solution for a serious radar--the one I had used a lot more than that so I had it completely switched off. It was a good radar--but used a lot of power. I just used a gen set through the battery charging output when I really needed it. The rest of the time I switched it off completely--and it should be easy to rig a switch to operate the relay at the helm station to turn it on or off. That is the good thing about relays--the operating circuit can be duplicated in any number of locations--it requires little power to operate it.

[bbalan]

Hi All,
The problem isn't that I can't put a breaker outside... it's that it's a ton of work and wiring. The power goes from the breaker panel at the nav station, through the headliner of the cabin and then up through the dash above the wheel. Can't break the radar cable after it exits -- those cables have a lot of wires in them and that would make no sense. So I would have to run from the headliner, down behind the helm, out by the helm to a switch, then back up to reconnect. A lot more wire and a lot of work since there is not great access. And obviously something I never planned on doing since I was switching out one stand-alone radar unit (Raytheon) for another.



It is one thing to have a paragraph about the current draw in the (very thick) manual (which you own after you purchase unless you download it). It is something that should be made clear before a purchase. Adding power doesn't make sense. Why would I add a generator or more solar to keep a piece of equipment running that is not being used? This is all about how the radar is used on long passages blue water cruising... it would be no problem for daysails or overnights. But long passage sailing uses more power than at any other time aboard our boat and that's when every amp-hour saved really counts.


I looked at solid state but they are inferior for picking up weather and that is our main purpose for having radar aboard.



Lastly, the Raytheon I just removed did not draw amps when the power was off. It has a standby mode which kept the magnetron warm... that made perfect sense. 0.8 amps continuous draw is nothing to a power, CG, work, or fishing boat. And that is the real market for this unit. I'm just saying that it is NOT a good unit for bluewater cruising unless you have a breaker right next to the unit.


Cheers,
Bruce

[Paul L]

Originally Posted by bbalan

Hi All,
The problem isn't that I can't put a breaker outside... it's that it's a ton of work and wiring. The power goes from the breaker panel at the nav station, through the headliner of the cabin and then up through the dash above the wheel. Can't break the radar cable after it exits -- those cables have a lot of wires in them and that would make no sense. So I would have to run from the headliner, down behind the helm, out by the helm to a switch, then back up to reconnect. A lot more wire and a lot of work since there is not great access. And obviously something I never planned on doing since I was switching out one stand-alone radar unit (Raytheon) for another.



...

Clearly this is a pain the butt.
The input power is not in the radar cable. It is in the power/signal cable. Thus one is not so critical in terms of signal integrity.
I see two choices.
1. Find where you hooked up the red/black 12v power. Break the red and run a new two wire cable back up toward the unit and put switch in.
2. Peel the insulation off the cable and extract tbe red wire. Put a switch on it and seal.

Yes, its an unplanned pain.

[Moontide]

Your right, shouldn't need more power, and bogus that manufacturer hides that info..


Did you see my post about putting in a wireless remote to a relay? Might be a solution while your out cruising.



Bill

[Paul L]

Originally Posted by Moontide

Your right, shouldn't need more power, and bogus that manufacturer hides that info..


Did you see my post about putting in a wireless remote to a relay? Might be a solution while your out cruising.



Bill

A remote relay would save running a wire.

Not sure how you say that the manufacturer hid the info. Its pretty apparent in the manual. The issue is more that it is unexpected and unnecessary. I've owned a number of pieces of Furuno gear including radars and they all turn off with the off button.

[AndyEss]

Hi Bruce - how is the Puddle Jump going?
Check Marlin P. Jones for remote controlled relays. I had several of these onboard at anchor in La Paz - too bad you hadn't identified the power draw problem then.
The remote controlled relays are pretty inexpensive (<$25?) and should be fine in turning the radar set on and off after the breaker with a little wire splicing work.
Fair winds.
Andy S/V Integrity