[Anonymous]

Can anyone tell me if it is normal for the standard voltmeter readings on the switch panel (B34 / 2001) to read rather higher than the actual battery outputs? When switched on but no engine running, no loads and the shore charger disconnected, a digital multimeter displays expected voltages (12.8v – 12.9v) for all batteries. The panel voltmeters, on the other hand, are showing anything from 13.9v to 14.8v. The domestic batteries (2 x 140ah) are new and the starter battery was tested by Lucas recently and found to be very good nick.

If anyone has any idea what the problem is, I’d be mighty obliged. I’ve googled around but haven’t found any mention about funny voltmeter readings so I’m baffled. Hope someone can help…

ATB, Mark

[Anonymous]

The panel voltmeters on my Bav 32 read exactly the same as yours. Could it just be a manufacturing display error on the Bav meters generally?

[Anonymous]

Hi David

That’s interesting – you’re the first person I’ve heard that’s suffering the same thing so yes, it may be more prevalent than I realised. I’ve heard from folks who have analogue meters and they don’t seem to have a problem. However, one respondent suggested there may be trimmer potentiometers at the back of the panel and I’m hoping that Clipper Marine will be sending me clear diagrams of the 420 panel (mine are unreadable in the Owner’s Manual). If I get any joy then I’ll obviously provide updates here…

ATB, Mark / Plymouth

[Anonymous]

Update: Had a look at the back of the panel yesterday and there are no obvious trimmer pots. The digital readouts appear to be sealed units with ribbon cables and it’s not clear (without the diagrams) which wires are +ve feeds from the batteries.

Mark / Plymouth

[Anonymous]

I’m in the same camp, so believe that it is a manufacturing or “max potential” reading.
In the real world the true readings are no where near….. I almost only look at the figure when I am off of shore power and the engine is not running to monitor the drain….. it seems to be more accurate then.

I dare say that there is a scientific answer to this, I’m just not the right person to give it. Hopefully someone else will?

?Confused.com?

[Anonymous]

That’s interesting, CaSam. So yours is more accurate when nothing’s happening (i.e. no shore power, no engine, etc.). Hmmm, Mine appears to be circa 1.5v over-reading at all times but usually more when charging (either S/P or engine). I think it may be time for a proper BM gauge and not bother with the 420 panel. A thought occurred to me yesterday – I have 2 x 140aH domestics in parallel. Whilst that shouldn’t make any difference at all, the standard spec was 1 x 140aH for B34 / 2001. I wonder if there’s any point in disconnecting one of them and checking. I know, I should have thought of trying that before…. 😳

[Anonymous]

I have a pair too, so let me know how you get on!

[Anonymous]

The built in voltmeter in my B39 2006 is spot on. I have a Nasa BM1 which over reads by 0.2 – 0.4v depending on the voltage.

John

[Anonymous]

Hi CaSam

OK, disconnected each battery in turn and still incorrect. Actual reading: 12.7v on #1, 12.8v on #2. Panel reading: 14.2v on #1, 14.3v on #2. Conclusion: the panel is a pile of poo and untrustworthy. Luckily, I’ve got an ST60 Multi, which shows Voltage under ‘environment’ details. The displayed value equates to the readings taken by 2 digital voltmeters. I wonder whether it’s possible to adjust the panel readouts by judicious use of a resistor in the live feed (if I can work out which it is and what resistor to use!)?

ATB

Mark, Plymouth

[Anonymous]

@figaro wrote:

Hi CaSam

OK, disconnected each battery in turn and still incorrect. Actual reading: 12.7v on #1, 12.8v on #2. Panel reading: 14.2v on #1, 14.3v on #2. Conclusion: the panel is a pile of poo and untrustworthy. Luckily, I’ve got an ST60 Multi, which shows Voltage under ‘environment’ details. The displayed value equates to the readings taken by 2 digital voltmeters. I wonder whether it’s possible to adjust the panel readouts by judicious use of a resistor in the live feed (if I can work out which it is and what resistor to use!)?

ATB

Mark, Plymouth

Hi Mark… where are the environment seetings on the ST60?
Steve

[Anonymous]

Hi Steve

If I cycle through the Chapter headings (Wind, Depth, etc.) using the bottom left button, eventually I get to ENVIRO(nment). Then I flip through the 2nd-left ‘Page’ button. It gives me: Water Temp -> Voltage -> Time -> Date, in that order. I assume the voltage reading comes from the supply to the Multi itself, rather than sourced via the data cable, so I guess it’s available on all Multis.

Happy hunting…

Mark

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