mcp

If you are interested in the size differences and electrical differences of lithium Iron Phosphate and Lead Acid AGM batteries, I have started to put my battery compartment together this weekend. On the left is a Vision FM100 AGM battery, 100ah @ 12v nominal, which is my start battery [currently running the fridge and lights] and on the right are 12 x 150ah LiFePo4 cells, 450ah @ 12v nominal. On the left the AGM weight is 32kgs and on the right the LiFePo4 pack weights all up 34kgs. On the left we have 30ah usable @ the recommended 30% depth of discharge and on the right w

If you have access to an oscilloscope and can use one? you could test it's output and input. There will be a common ground and a input signal with a AC signal that the unit is rated for ie; 50kHz, 80kHz, 200kHz, 235kHz, etc. The output signal will be similar frequency but the amplitude will vary a lot. If you have a frequency generator handy as well we can measure the impedance magnitude and series resistance. Those two figures should be very close if the transducer is working mechanically correct. But. You could also check that its output is working by turning it on briefly a

How tight of a radius could you do? I need to cut two 190 mm round holes.

Do you have any pictures of the blade you acquired and how long did each one last? I am cutting 12mm - 15mm solid polyester based fibreglass.

Solid fibreglass is very very hard on jigsaw blades it seems. What type of blades have people had success with? Or do I just need to buy lots?

Now thats a novel idea.

Yeah I saw that, but with limited replys and its now 7 years later I had figured that things would have changed?

What is everyone using for bilge and locker paint? I have been recommended Bilgekote and use this with Yacht primer from international paints. Are there similar alternatives?

I have been observing PHAD been given some attention and a lick of paint over the last few months in Whangarei. She is a nice looking critter.

No temperature compensation in a hot boat would do that.

That's a clever idea as long as your not expecting great accuracy from a simple circuit. You could do it with a normal diode as well and no need to have a bias current? More parts though. Don't forget to check max operating temp of the diode your using as well. Most are 150 degree-ish rated or less.

I like the idea of donating it to someone doing a sea survival course. If anyone has some contacts? If I get no luck there I will flick you a PM Clipper.

What is a sensible thing to do with a old out of date life raft? I doubt it is worth anything?

*bump*

I agree with Wheels. It looks okay to me as well. The graph shows a steady decline in current and drops to a float voltage. There are defiantly conditions where absorption can be omitted if all other parameters are met. But is is really hard to fault find something like this from such a high state of charge. Try it from 60% SOC and lets see those graphs and make sure you unplug any solar/wind you have. Another thing that is worth pointing out is that alternator charging is only really efficient for the Bulk stage of a batteries charge cycle, use solar [or maybe wind] to top

I found this one quite interesting as well. Not directly boat related but there are some definite parallels.

That was a good watch. Here are a few I found to watch recently.

I heard they were filling them with sailboat fuel?

That was not a good idea even if he could get back to the boat. I hope they are a sealed pack with inbuilt BMS with hi voltage disconnect, if thats the case they should be fine. It they are individual cells, like a prismatic. They will be likely toast and that will have to be chalked up as experience unless his insurance company is dumb.

It doesn't. You will expose each to each other directly.

Check the cables are adjusted properly to allow the wheel that turns the butterfly and lifts the jet to return 100% to rest on its stop. If in double remove the cables and control the wheel with your fingers.

I am just going to use a DC-DC charger to get around all the pitfalls of these older systems. Especially now they are are reasonably cheap now.

You don't need a BMS for a lithium iron phosphate either. Its just that peoples knowledge of batteries is based around Lead acid variants and they think they know stuff. So the BMS is actually there to protect the battery from the human in most cases. Also, thermal runaway does not happen with the lifepo4 types used in marine batts. Flooded lead is by far the most dangerous battery technology used on boats. Anyway, of topic. So back to the original question. When you head off for the horizon, are you going to have refrigerators and inverters, etc? or just what you

Just a thought. Its not the time server you are using giving an incorrect time? Most software doesn't like working in the past.

*bump* I would much rather sell this on crew.org and give some of the proceeds to this website than do the same on trademe. But if there is no interest on here I will list it on trademe soon.