Messages

Wow. Thank you.

That worked. I'm so embarrassed I was unable to find that fixya page.

Thank you. Thank you. Thank you.

You saved a great deal of money and bother. I was hours away from breaking down and upgrading. I will work hard this weekend to pay your good deed forward.

My chart plotter is acting up. It is an old unit, a Simard CP33. Trouble starts as soon as I power up (the PWR key works to start it). The splash screen comes up but a message should come up (hot ENT to accept conditions) but the unit just hangs. The unit is unresponsive to all inputs. Even the PWR button does not turn it off.

First, any suggestions on fixing the problem? I can't think of anything I've done to cause a problem. I have checked with a multimeter and it is getting plenty of power. The manual offers no advice, nor does simrad online customer service.

I may need to consider replacement options. I went to my local (awful) marine store. They seemed pretty clueless. They said there is no no way for the old transducers to talk to new equipment.  Is the store correct? Do I need to put another hole in my boat and buy a new transducer? The CP33 takes a round 7 pin connector to which I think I send depth info. Do modern chart plotters accept that connection? If not is there some sort of a bridge to connect a legacy transducer?

Any suggestions on what to get? I don't use my chart plotter for much. I much prefer to use my iPad. In fact, I think it would be a better system if I just had a headless transducer sending out depth information so my iPad could read it. I suppose there could be some value in a modest chart plotter or a small unit showing speed course and depth. Any suggestions on what to look for? I'm hesitant to put down big money because I just don't think I need all that much.

One other thing, some of the chart plotters came as a package with a transducer but the store said they won't work on a sailboat. Does that make sense? Do I need a special transducer to work with a sailboat? What do I look for in a transducer?

Thank you.

David Hopkins
1990 C30
Vancouver BC

Thanks Dave. Contacting Rolls is a good idea.

Thanks for your answer. But I think things are a bit more complicated.

We know a battery's voltage will drop under load, but the question is by how much?  I'm pretty sure my battery's voltage is dropping too much.

The big problem I am experiencing is that once my house batteries are discharged to about 70% my batteries are at 12.0 volts. As I understand it, this is where you start causing damage to your batteries.

This site, for instance, suggests that under load my batteries should initially be above 12.5 volts and should remain above 12 volts past 50% discharged.
https://marinehowto.com/under-load-battery-voltage-vs-soc/

Chart Resting Voltage              Actual Under-Load Voltage
90% 12.75V                                                      12.55V
80% 12.50V                                                      12.50V
70% 12.30V                                                      12.37V
60% 12.15V                                                       12.24V
50% 12.05V                                                      12.11V

My batteries are delivering lower than expected voltage.

My house batteries consist of 2 Rolls AGM. They are 115 Ah for a total of 230 Ah. I bought them about 2 years ago.

When my batteries are fully charged up and I put a 11.5 amp load on them, the voltage steadily drops and after 2-3 minutes settles at about 12.3 volts. After a few hours of a steady 11.5 amp load, when my battery monitor shows I should be at about 70% capacity, the battery voltage has already dipped below 12 volts.

I assumed my batteries were toast. But when I did a 20 hour test on them they performed reasonably well. They lasted over 17 hours before the voltage got to 10.5. My battery seller says Rolls will not warranty replace a battery that performs that we on the 20 hour test.

I'm quite sure I don't have a significant draw on my batteries that is not being recognized by my battery monitor because when I take my batteries off the charger and leave them for 24 hours the resting voltage is about 12.7.

My questions.

1. Am I correct that this is unexpected behaviour? What voltage should I expect a properly working battery to deliver when under load?
2. Do the batteries need to be replaced?
3. What else could be causing this voltage drop?
4. What could I be doing to my batteries to have caused this?

-David Hopkins
Vancouver, BC
1989 Catalina 30

Thank you all for the help. Edson did not respond to my emailed inquiry. Catalina Direct thought my idea was correct. I will update after I do the upgrade.

The shaft that my steering wheel slides onto moves bit. The shaft goes in and out about a millimetre. It also seems to move about a millimetre up and down. As I understand it the shaft should only spin. There should be no play in/out or up/down.

I don't notice this much when I am hand steering but when I am under autopilot the wheel shakes or shudders.

Any suggestions on diagnosing/fixing this issue?

I am hoping that if I replace some of the shims using this kit the problem will go away. The rep I spoke to at Catalina Direct was not very hopeful.

https://www.catalinadirect.com/index.cfm?fuseaction=product.display&product_id=2962

David Hopkins
Vancouver
1990 C30

My boat spends much of its life safely plugged into shore power at the marina. I have a a fridge which I leave running all the time connected to DC. When running it draws about 5 amps of power. The fellow who repaired my fridge advised the fridge will last longer turned on and running rather than being switched off. An electrical expert I spoke with said it was fine to leave the fridge on when connected to shore power with the battery trickle charging. I have a ProNautic 1220P (20 amp) charger. All was fine until I read this post which is stuck to the top of this message board.

http://c34.org/bbs/index.php/topic,4352.0.html

I'm trying to come to terms with the suggestion that constantly sipping from my battery will shave off 35-40% of my battery's life.

I find it odd that:
-Experienced cruisers I have talked to have not heard that this is a bad practice
-A cursory search of the web does not come back with clear warnings that this very common practice is killing our batteries.
-the warning against this practice was buried in a post reviewing a particular charger
-the post contains no citations for the dramatic claim

Help me out guys. Are there studies documenting these concerns? Why are batteries so damned confusing?

I have ordered a pair of Firefly batteries to replace my old AGM batteries. Anyone know if they are more or less susceptible to this issue?

-David Hopkins
1990 Catalina 30 #5845
Vancouver

So the saying "build a better mousetrap and the world will beat a path to your door" is incomplete. You need to also build a good distribution network and quality control.

Thanks Maine. Interesting theories.

It is time to replace the house batteries on my 1990 Catalina 30. I can fit two group 31s as a bank under my dining bench. After some research on what battery to buy the clear choice is a pair of Firefly batteries.  https://www.bruceschwab.com/advanced-energy-storage-systems/firefly-energys-oasis-group-31/

I'm a bit puzzled at how clear the choice seems given that Firefly batteries remain a niche product.

It seems to me that for about 2-3 times the price I'd pay for a flooded or AGM battery the Firefly gives me:
1. maybe 8-10 times more life (3600 cycles to 50%DOD)
2. more usable battery capacity because these batteries can be regularly discharged 80% or more without damage. This is impossible with flooded batteries and likely destructive to most AGM batteries.
3. partial charging. These batteries claim not to suffer sulfation even if repeatedly partially charged. This means I can anchor for longer. I don't need to run my engine needlessly to push my batteries slowly up from 85% charge. When cruising I don't have to spend a night at a marina every week to get my batteries up to 100%.

If all this battery did was deliver on promise 1 it would make mathematical sense to buy these batteries over anything else I've considered. Item 2 is a massive bonus. Item 3 is great and it also locks in the other benefits. I'm more likely to actually get to use the extra cycles the battery promises because I won't ruin the battery through partial charging.

Three questions.
A. Why are the experts lukewarm about these batteries? Practical Sailor confirmed much of the marketing claims but stopped short of recommending the batteries saying further testing is required. Nigel Calder said much the same. I understand these batteries were developed 10 years ago. Why is there not better data on whether they truly deliver the promised number of cycles in the wild?

https://www.bruceschwab.com/wp-content/uploads/sites/86/old/firefly-testimonial-nigel.pdf
https://www.practical-sailor.com/blog/Can-Carbon-Foam-Batteries-Meet-Hype-11694-1.html

B. Why do Fireflies remain niche items? Obviously it's a big ask to shell out 2-3 times more money for a battery up front but overall cost of ownership appears to be much lower. Is the choice not quite as obvious as I have made it seem?

C. What else might cause these batteries to die? If I keep them above 50% DOD it could be decades before I cycle my batteries 3600 times.

Cheers.

-David Hopkins
1990 Catalina 30 5845
Vancouver