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A:  

Hi Ed,

It certainly is distressing to realize that the AC grounding wire, a critical safety component on any boat, is missing. You’re right - the AC grounding wire (green colour) is intercepted right at or very near the shore power receptacle, and both severed wire ends are connected to the galvanic isolator. When all AC sources of power are disconnected, you can test a GI for failure by simply performing an ohm's test. A failed GI ohm's reading should show some resistance, but very little. Only a diode test in one direction can show if a GI is working properly.
 

Posted on: May 14, 2012

A:  

Hi Steve,

The iPad Navionics version provides better chart detail then the iPhone version. The difference between each app is similar to the difference between gold versus platinum charts. In terms of value, the iPad version is great and I highly recommend it. That being said, both versions are useful and you can definitely benefit from having them both.

 

Posted on: May 14, 2012

A:  

Hi Jim,

The V-Belt can handle only up to a 90 amp alternator without dusting or heating, while the serpentine belt can handle much more and is a better choice. A flooded battery can handle 25% of capacity, while an AGM battery can handle 40% of capacity.

There are two possible solutions to your question:

1. Switching to the serpentine belt system

I would suggest getting a second alternator instead of replacing your current one; there is no point in removing the current capacity you already have. Volvo makes a second alternator kit for this engine. They also make a kit that converts V-belt to serpentine. I'd suggest switching to the serpentine belt system.

Installing another 115 amp alternator on your second alternator kit is the right approach. Both of your alternators will have a combined output of 230A. This value is certainly higher than 25% of the maximum charge rate for a flooded battery (700 Ahr). However, this means your alternators won't be running at full capacity and can potentially burn out prematurely. Consider getting a regulator which senses the alternator temperature, that way you can prevent your alternator from working too hard. Also, note that Volvo engines are quite particular in their alarm systems and a smart regulator installation will not be a simple project. You'll need to do a few extra steps not discussed in any manual to avoid your engine charge alarm to turn on when it should not.

2. Staying with the V-belt system

If you stay with the current V-belt system and do not upgrade to serpentine belt, then there maximum alternator should be around 90 amps, but 115 amps might work if the tension is just right on the belt. Through experience (with external regulators), they should know if it experiences dusting. I would suggest getting a hot-rated alternator that is wounded for high output at a low RPM. Both Balmar and ElectroMaax offer these types of alternators. Also, it might be worth considering a regulator that throttles back the field voltage (I.e. the driving force) so that the alternator does not work at maximum capacity (e.g. 70% or 80%) in the event of dusting.

 

Posted on: May 14, 2012

A:  

Hi Pat,

There is really only one solution to this question. Unfortunately, you need a 32V to 12V converter. Otherwise he should consider getting a dedicated 12V battery and small charger if he doesn't like the pricing of the converter. You absolutely cannot tap into a 12V cell and discharge that cell. We have seen it numerous times and it destroys the 12V cell prematurely, and leaves the whole 32V cell ruined.
 

Posted on: May 02, 2012

A:  

Hi Denis,

Here are the answers to your questions:
1) A two output battery charger can handle two battery banks. A battery bank can consist of one or many batteries.

2) Typically battery chargers are set to charge one battery type only. Batteries within a bank should be the same model, age, and type. But a charger can charge many batteries as long as the batteries are of the same type.

 

Posted on: Apr 23, 2012