Unadvertised draws on house battery

[JohnL]

I just installed the Victron 712 battery monitor on my 2019 R29s. When I turned on the house battery bank, the monitor told me that equipment on the boat was drawing down almost 3 amps even though I had turned nothing on. Neither the solar panels nor the shore power charger were turned on. So I started looking around. First stop, the instruments at the helm. Both the autopilot and Garmin display had activated underneath their covers despite the fact that I always turn them off manually when I’m finished using them. I turned them off but there was still a constant draw of over 1 amp. I did a careful inventory and couldn’t figure out what it was. The propane monitor LED is always on but I it’s not driven by the house battery. I know the two bilge pumps check in briefly every couple of minutes but this draw is constant, not episodic. Nothing is plugged into the 12 volt charging outlets. There are no lights on. The refrigerators and wine cooler are off.Hmmmm. I’m running out of ideas.

Any suggestions gratefully received. Over 1 amp per hour adds up when you are on the hook over a couple of cloudy days. I’d like to know what’s stealing my precious electrical current.

 

[Wee Venture]

Make sure the stereo isn’t on, maybe hidden by the cover over the controls. The TV will draw a little on standby but not that much. The inverter will draw about that much if it is turned on, even if nothing is plugged into it.

 

[Pilotnavigator]

Has anyone not heard of a DC current clamp meter by now! Get one and use it to investigate all current issues. You can make all the suppositions and ask all the questions but the only way to prove what current is going were is to test the lines with a clamp meter! Your boat may not be wired as is others so test yours!

 

[Kevin Lamont]

I just installed the Victron 712 battery monitor on my 2019 R29s. When I turned on the house battery bank, the monitor told me that equipment on the boat was drawing down almost 3 amps even though I had turned nothing on. Neither the solar panels nor the shore power charger were turned on. So I started looking around. First stop, the instruments at the helm. Both the autopilot and Garmin display had activated underneath their covers despite the fact that I always turn them off manually when I’m finished using them. I turned them off but there was still a constant draw of over 1 amp. I did a careful inventory and couldn’t figure out what it was. The propane monitor LED is always on but I it’s not driven by the house battery. I know the two bilge pumps check in briefly every couple of minutes but this draw is constant, not episodic. Nothing is plugged into the 12 volt charging outlets. There are no lights on. The refrigerators and wine cooler are off.Hmmmm. I’m running out of ideas.

Any suggestions gratefully received. Over 1 amp per hour adds up when you are on the hook over a couple of cloudy days. I’d like to know what’s stealing my precious electrical current.

Hey John,

Hope all is well with you and was great to see you again at the rendezvous in Roche Harbor.

What you could do to see what is causing the draw is start pulling fuses for items at both fuse block locations in the head and 1/4 berth. Everytime you pull a fuse check your meter to see if it goes down or stays the same, if it goes down that would be a source of a draw. A list of a few items to keep in mind that pull power even if not on or in use:

-bilge pumps
-propane solenoid
-stereo power/memory
-CO detecors
-head toilet controller
-Garmin devices (very slight amount even if off)

I am sure I am missing a few but gives you a good idea. Also be sure to do this test with the engine and thruster battery switches in the OFF position. Hope this helps you out and feel free to reach out to me direct if you have any questions. Hope to see you in Seattle sometime!!

Thanks,
Kevin Lamont

 

[SlackwaterJack]

I'll admit I'm no "rocket surgeon" or even a " brain scientist".....
…. but is the battery monitor drawing any power? display, memory, fan,.... ?

 

[JohnL]

Thanks everyone. Very helpful suggestions that I will pursue. A couple of points. I have programmed my inverter to be off unless switched on and it is disconnected from the battery bank unless I am using the shore power battery charger. The DC voltmeter and the radio memory take a bit and are always on. Good points. And, of course, I forgot the LEDs for the electric toilet, the TVs and the CO detectors. It all adds up. I’ll pull some fuses and see if there are any significant offenders. I might even get a clamp meter after that solid scolding from John, Pilot Navigator.

I didn’t realize the Garmin equipment might be drawing power even when off. Speaking of which, does anyone know why the Garmin and Autopilot displays come on every time you turn on the house battery bank? With the covers on, they could be sucking serious power for a long time without being noticed.

 

[bill46]

Garmin can be programmed for auto on.

 

[JohnL]

Thanks Bill. ‘Auto off’ is a good move especially if you use the boat as a man cave during the darker months and don’t need navigational help at the dock. The chart plotter and autopilot really take a lot of power.