385/388 - Leakage current?

Print Page | Close Window

Leakage current?

Printed From: myHanse.com
Category: Hints & Tips
Forum Name: 385/388
Forum Description: 385/388 Hints, Tips and News
URL: https://www.myhanse.com/forum_posts.asp?TID=10705
Printed Date: 27 March 2026 at 03:51
Software Version: Web Wiz Forums 12.06 - https://www.webwizforums.com

Topic: Leakage current?

Posted By: chrgra
Subject: Leakage current?
Date Posted: 12 April 2018 at 22:32

During replacing the batteries, I discovered a leakage current.

Does some one have any idea where to search?

Wall power disconnected
Vhf off
Engine cabine light off
Roof light also off

Regards chris

-------------
Hanse 385 Charlotte #363

Replies:

Posted By: StavrosNZ
Date Posted: 13 April 2018 at 01:06

smart regulator for the alternator and charging might be the culprit, many brands require permanent live supply. do you have any LED or lights on in the engine bay when power is off?

do you have amp gauge like BEP DCSM or similar, these monitors, gauges draw small current all of the time

also the bilge pump switch which is permanently live will draw small amounts

-------------
Stephen
2010 H400 #691, Auckland, New Zealand

Posted By: Wayne's World
Date Posted: 13 April 2018 at 11:05

Chris,

How much current leakage did you find - 1 amp, 2 ,3 ? How did you measure the current leakage?

-------------
Wayne W
Cruising, currently in the Pacific until the end of 2026.

Posted By: High Time
Date Posted: 13 April 2018 at 15:04

Yes it would be good to know the magnitude of the leakage. Also is it the engine battery or the services battery?

If the services, then there are several possibilities. There is a set of connections on the fuse panel (it's the first 14 connections on the 415) that are 'always on' (i.e. even if the battery switch is turned off). These are typically used to power the courtesy light above the companionway, the Fusion radio/CD station memory, aircon if fitted, sometimes the VHF (depending on who fitted it) and any other additional equipment that might benefit from a permanent connection e.g. Navtex; also the battery combiner and any battery monitor that's fitted. It could be any of these. If the leakage is of the order of a few 10s of milliamps, I wouldn't be too worried. If it's over 100mA then I would want to know exactly what.

You could remove each of the fuses in turn while measuring the current to get an idea of which connection it is. You might then need to refer to the circuit diagram for your boat to determine what item is powered through that connection.

-------------
Roger

High Time (415 #038)

Posted By: chrgra
Date Posted: 14 April 2018 at 07:01

It's the service batterie,

When reconnecting the batteries with (i thougt) everything switched off i got sparks.

I can check with the first 14 fuses.

I also want to install a battery monitor. The victron bms 700 looks reasonable priced.

Regards chris

-------------
Hanse 385 Charlotte #363

Posted By: High Time
Date Posted: 14 April 2018 at 10:15

If you're seeing a spark then it is unlikely to be any of the items I mentioned above; these should normally only take a few miiliamps.

Was the service battery switch on or off when the spark was observed?

Do you have a bowthruster? If so, it might be the battery to battery charger.

It could also be the mains battery charger - even if not connected to the mains there are large capacitors that could be discharged.

Finally (for now) it could be the battery combiner as mentioned above.

I suggest you need run your mains battery charger for some hours to get all batteries to the same state of charge and then try disconnecting the service battery and reconnecting. If you have an ammeter then it would be worth measuring the current on reconnection. As I said before you only need to worry if the steady state current is above 100mA.

Regarding a battery monitor I would agree your suggestion of the Victron unit. I have the 600 which preceded the 700 and has been invaluable for monitoring charging and discharging of the service battery. I am less concerned about the engine battery.

-------------
Roger

High Time (415 #038)

Posted By: Snow White
Date Posted: 14 April 2018 at 14:24

For the VICTRON, this document might be interesting...

uploads/4978/Manual-BMV-700-700H-702-EN-NL-FR-DE-ES-SE-PT-IT.pdf" rel="nofollow - uploads/4978/Manual-BMV-700-700H-702-EN-NL-FR-DE-ES-SE-PT-IT.pdf

-------------
Have a good Day.

Posted By: Captain Cook
Date Posted: 14 April 2018 at 18:54

If you have a diesel heater, it is normally connected directly to the battery, with a fuse in the battery compartment. The reason is, that when you turn off the main switch, the heater may still need time to close down. In my boat I also have seen a spark,when connecting the battery terminal.
I suppose it is caused by the heater and/or the HF radio. Those are the only items that recieve power when the main switches are off.
Electrical equipment which contain a capacitor, will draw a current, because the capacitor will lose the charge over time. This is probably the case in my HF transciever.

-------------
Freya H400 #27 (2006),2-cabin, 40HP 3JH4E, 3-blade Flexofold, Aries LiftUp Windvane, Exturn 300, Jefa DD1,Simrad NX40,Icom M603(VHF)+M802(SSB)

Posted By: Axel
Date Posted: 16 April 2018 at 16:17

I have the Victron 700. It is very useful. I found out that there are 7 W when the engine is on, but not running. It is probably the motor panel.

Axel

-------------
Hanse 385 #434 Nyanga 2