Alternator alarm sounds at idle

[boeing1]

agree on the low oil press alarm. as stated above, suggest first check your Idle speed, then put in in gear and recheck to see if the drops to trigger the alarm

[Cheechako]

I've not heard of an Alternator alarm either, but if you have one, is it possible that your regulator doesnt kick in at low rpm? That happens a lot for tach sensors off alternators.

[Paperbird]

It might be the belt alarm, but not because of the belt. On our beta engine with external balmar regulator, when the batteries are fully charged and the solar panels are holding a higher voltage in than the balmar setpoint, the balmar turns off the output from the alternator. Then the beta alarm panel thinks a belt must have broken since there is no alternator output.

If your primary alternator is putting out enough to turn 'off' the alternate alternator, the alarm panel may think the belt broke

Our answer is to either turn off the solar panels or to turn on something like radar that draws enough current to keep the balmar regulator happy


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[Psalm8]

Hi. I have a D2-40 and the alarm sounds at idle when the current draw is too high. It is usually when the batteries are down and the Sterling DC DC charger is pulling around 85 amps from the alternator. I simply raise to fast idle while we get underway and the charger puts the initial charge in and things settle down. Still have original 125 amp alternator and 500ah battery bank. Same setup since 2007.
So, I suggest you check initial current draw. Rebuilt alt may have less capacity if parts have been replaced.
Cheers

[Seighlor]

I do not have an alternator alarm. However, I've noticed that when the fridge is operating the ammeter may drop to the negative side when operating at idle. As noted by Psalm8, just need to provide a few more rpm's to provide for the 30 amps drawn by the compressor.

[barnakiel]

1) Make sure the alt did kick in. At times they need to be reved up to kick in. Once they kick in, they should not sound.

2) Make sure the cabling and connectors are fast and secure, electric alarms at times sound when cabling and connectors move under way (rare but did happen to us once).

3) If there is an electronics block, if everything is fine (you have charge) and the alarm sounds - may be a sign the block is going nuts. VP staff can check it in a VP service point.

b.

[landonshaw]

I checked my lights, it is the battery light. Engine idles at 850 rpm. Will heck cables and the other suggestions.


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