Balmar MC618 charging pattern vs alarms

[skippeer]

Installed XT170, pulley kit and MC618 on a Volvo Penta D2-55 A.
MC618 terminal #17 connected to Penta engine panel via inverse relay.

To high extend happy with the installation but the Penta engine alarms are annoying. The alarms seem to be frequent with high SOC 94-100%.

Below is how it locks after a night with shure power, short engine drive to receiption and after that slow drive to sea.
Solar panel charging disabled for todays test.

Each time with negative current triggers the alarm.

Is this expected pattern with nearly full batteries?

Considering to set bdL=off and ALL=12.1 (AGM startbattery SOC 50%).

[hlev00]

Does it only happen when solar is charging? This is a common situation but easily remedied. The solar absorption set point is higher than the Balmar. When the batteries are approaching full, the solar keeps the voltage up and the Balmar sees this, thinks the bank is full and so stops charging which the panel sees as an alternator failure. Lower the solar absorption point to a voltage below what the Balmar is set for.

[skippeer]

Originally Posted by hlev00

Does it only happen when solar is charging?

Yesterday was a day for verification if the classic Penta charging alarm was the root cause as you suspected, it wasn’t. Only alternator charger after leaving dock.

Solar panel charging disabled the night before leaving dock.
No wind. no hydro charging.

Shore power Victron IP43 at dock => Battery banks SOC 99.9% before engine was started that morning

Bulk/Abs 14.2 volt
Float 13.5 volt
Hybrid battery solution with X2 BMS; Service LFP & Engine AGM.
AGM is fixed connected to ”charge bus bar”, alternator is also connected to this bus bar.

My interpretation of the graph is that Balmar regulator is testing/measuring battery status when charging is shortly stopped, multiple times.

Is this a normal charge/measure pattern i.e. Balmar devices are healthy?

A Penta engine panel with charging warning lamp/buzzer will drive me mad with default setting ”bdL = on”.

[skippeer]

10-15 years ago did Rod Collins suggest a manual switch to disable alternator charging during a period of 30 min after leaving the dock with fully charged batteries.
I expected that Balmar would have addressed that old issue by now, the triggers for Dash Lamp and/or bdL config could be improved/better explained in manual.

[Stu Jackson]

Originally Posted by skippeer

Shore power Victron IP43 at dock => Battery banks SOC 99.9% before engine was started that morning



>>>>>>>>>>>




My interpretation of the graph is that Balmar regulator is testing/measuring battery status when charging is shortly stopped, multiple times.

Is this a normal charge/measure pattern i.e. Balmar devices are healthy?

A Penta engine panel with charging warning lamp/buzzer will drive me mad with default setting ”bdL = on”.

Am I correct in understanding that your bank was at 99%, i.e., FULL when you did this test?

If so, the test was worthless.

Why? Because unless and until a bank needs to be charged by ANY source, no charging will occur. In this case, the sense wire on your external regulator is checking repeatedly for the actual battery voltage.

Try DEPLETING the bank before you try this test.


Unless that wasn't what you were testing. In any case, the Why? Paragraph still applies.

[skippeer]

Hi Stu,

for me was this test;
• without solar panel charging
and
• with full batteries when leaving dock
key to understand if the experienced symptoms were related to additional chargers or not. (Classic Penta issue with charging alarm due to solar panel charging interfering with alternator charging.)

Your reply confirms that the charging pattern is expected and no defect Balmar components. Thanks for that input.

The attached graph above shows the successful bulk phase (time 1 x 6 min) and the reason of the annoiyng buzzer sound after bulk.

Today did I set ”bdL = off” with a hope to avoid future buzzer sound when SOC is 94-100% and no charging continue after bulk phase.