on board pc for navigation.. power consumption...?

[contessaman]

hi all,

im not particularly computer orientated but somebody gave me some good chart plotter software and a whole load of chart coverage. Been running it on the laptop initially. not the most frugal thing battery wise using an inverter to make 240volts to run a dc power supply to power a laptop.

thought I'd have a go at building a marine pc. Its all in bits (but working)on my study table at the moment but the parts I have picked up for a few quid here and there off of ebay. Im trying to get the current consumption as low as possible.

thought i'd offer up what I have achieved and see what others have come up with if anyone has done similar..

its a 'mini itx' motherboard which seems to have everything built in. 1ghz.
12v atx psu designed for boy racers in car pc based stereos
monitor is a 12 inch lcd off a supermarket till (it runs off 12 volt!)

together, with the usb gps reciever plugged in and running the transas software it all takes just over 2.5 amps.

im looking at loosing the hard disk in favour of one of these solid state memory based ones
also reckon I can loose the only fan - off the processor by using a bigger heat sink. less power and silent then too.

might get under 2 amps then. which cant be bad with a big 12 inch display. anyone done better?

dont know how that (current)compares with the latest off the shelf chart plotters as I dont have one? but the pc can do navtex with an ssb rx and also with a wifi dongle internet in the marina is handy for weather gathering too.

I only wish I had held out for a touch screen display so I could have done away with the keyboard and mouse...

im going to try to get the current as low as I can then think about some sort of case for the computer bit then maybe a teak frame for the lcd so it can be mounted neatly at the chart table.

all thoughts comments welcome!

yes I will always carry and use valid paper charts too by the way. especially with my 'click... click... ...s*it' luck with computers.

 

[daveyw]

Sounds great. Would love to build one myself if I knew what I was doing. If you can get the power really low = less heat = less cooling so could it be fully enclosed/watertight? Maybe give it a squirt of nitrogen before sealing it up to reduce chance of condensation?

 

[idpnd]

Thats exactly what ive got - fanless (out of box) zotac ion, it can decode HD videos as well so is my main pc whilst living on board.

Am also using an SSD 64GB all very affordable.

I use a wifi amplifier on the pushpit for marina wifi btw

Enjoy!

 

[RestlessL]

With a fully charged battery my Panasonic M34 takes 1.1A, or 0.7A with the screen blank.

 

[contessaman]

Sounds great. Would love to build one myself if I knew what I was doing. If you can get the power really low = less heat = less cooling so could it be fully enclosed/watertight? Maybe give it a squirt of nitrogen before sealing it up to reduce chance of condensation?

its not hard really. Have a go! i dont know much about them. you get the motherboard, plug the power supply in etc. its all just plugging stuff in. I taught myself all I know by taking apart my old home pc - I was bound for the bin so I took it apart to see how it worked.

re: the case i think it will have to 'breathe' so that the heatsink can do its stuff. unless the whole case is metal and is thermall coupled somehow to the processor.

but yup I agree that the way forward is keeping the ampage and hence heat down. I think memory takes power too. I dont think the nav software needs the 1 gig of memory I have onthe board so if it wil run with 256 meg I might try that.

 

[nrbx]

http://linitx.com/

These guys have loads of good stuff! From low power 12 volt boards, to 12 volt plug ins to power normal pc's off of 12 volts

 

[fishermantwo]

On my yacht I use a Toshiba Tectra, 12" screen. Max current is 4 amps. I have removed the battery and it is driven straight off the ships 12v supply, no step up ****. Because it is not charging a battery the power consumption which I have not measured would be low. I also bought a Toshiba Portege off eBay as a spare for $15. 10" screen, max current with battery 2 amps.

 

[contessaman]

With a fully charged battery my Panasonic M34 takes 1.1A, or 0.7A with the screen blank.

wow thats good. how do you power it? most laptops I have seen are 18 volts in so the only way I can see for making that is up to 240 ac then back down to 18vdc. then one has losses in the process plus the quiescent (if thats how you spell it) current of the invertor.

I did notice my really old compaq laptop had a 10.4 volt battery despite the 18v in. thought of cutting up the old battery (using it as a plug) and using a voltage regulator to make 10.4 from the 12-14v ship supply. but the battery seems to have about 8 connections which is beyond me. also that old laptop cant cope with xp. although the transas stuff works on win2k niether of my usb gps rxrs will.

 

[contessaman]

On my yacht I use a Toshiba Tectra, 12" screen. Max current is 4 amps. I have removed the battery and it is driven straight off the ships 12v supply, no step up ****. Because it is not charging a battery the power consumption which I have not measured would be low. I also bought a Toshiba Portege off eBay as a spare for $15. 10" screen, max current with battery 2 amps.

did it have a 12 v battery or did you need a dc voltage reg to drive it? also how did you know which pins to connect the 12v to as the batteries seem to have loads of pins on them?

 

[Searush]

My netbook uses 1.6A according to the PSU transformer & runs at 12v off the car or boat batteries. Cost £150 - plus a spare copy of Windows to replace the Linux it came with.

Works well, but for a small boat with just 2 batteries & no extra charging capability, I can't really leave it on for a long passage & still guarantee to be able to start the engine unless I let it kill just the domestics battery. I also need to be a little careful with forum fiddling at night as I will need another 0.8A to charge the mobile for 3g access - I have no intention of running the engine all night for charging.

 

[Amulet]

hi all,

im not particularly computer orientated but......

Give us a break - if you are doing transplant surgery on computers you must be a geek (no insult)

I'd actually be anxious about what to do if it breaks. But I bet you are having fun!


I carry a couple of obsolete laptops and double up on all the other bits. Standard plug and play. It does hit 5 amps on occasion but averages under 4. I really stuggle for amps on my boat but manage. I feel I can cobble something together if someone spills beer on the computer,or any other part of the system fails.

I now have a total of five PC nav packages running, which is a load of bo||ocks, but my kind of fun.

 

[fishermantwo]

did it have a 12 v battery or did you need a dc voltage reg to drive it? also how did you know which pins to connect the 12v to as the batteries seem to have loads of pins on them?

The Toshiba has a 15v battery. I spent $2.50 on a two pin power plug to plug in the normal power point on the back of the laptop. Two core wire to ships supply. The outside of these power plugs is usually the negative.

 

[RestlessL]

how do you power it?

Just a standard (3rd party) auto power supply. Much more efficient than using an invertor (but I haven't measured this)

Power consumption can be much greater if the battery is discharged - I used to have an old IBM T23 which took 6A when the battery was fully discharged.

 

[idpnd]

re: the case i think it will have to 'breathe' so that the heatsink can do its stuff. unless the whole case is metal and is thermall coupled somehow to the processor.

I found I had to leave the top off for it to "breathe", doesnt really matter its down under the nav table

 

[westhinder]

I use a purposebuilt (by my computersavvy nephew) fanless mini-itx for navigation. The box is ribbed to disperse the heat. It is suspended under the bookshelf next to the chart table and has a 1 cm clearance. In the past three years I have never had a problem with the unit overheating, not even on those rare hot days in summer, nor when the computer ran for 36 hours on end.
I have never actually measured power consumption, but I have a feeling the screen is the bigger consumer. It is a 17" 12V screen, powered through a 12-12V converter for stable current. The screen is set to power down after 30 seconds.
I keep an eye on the state of the batteries, but so far the Aero4gen seems to keep them on acceptable levels. The fridge puts a heavier drain on them than the pc.

 

[st599]

I use a purposebuilt (by my computersavvy nephew) fanless mini-itx for navigation. The box is ribbed to disperse the heat. It is suspended under the bookshelf next to the chart table and has a 1 cm clearance. In the past three years I have never had a problem with the unit overheating, not even on those rare hot days in summer, nor when the computer ran for 36 hours on end.
I have never actually measured power consumption, but I have a feeling the screen is the bigger consumer. It is a 17" 12V screen, powered through a 12-12V converter for stable current. The screen is set to power down after 30 seconds.
I keep an eye on the state of the batteries, but so far the Aero4gen seems to keep them on acceptable levels. The fridge puts a heavier drain on them than the pc.

Lowest I've managed is about 3W average, 6W peak for the computer using a Fit-PC2. Using Navigatrix as an OS, it runs fine. You use the power manager to ensure efficient running.

Can easily play DVDs ripped to Xvid, Run OpenCPN with AIS and GPS, use the Web, Emails etc.

http://en.wikipedia.org/wiki/Fit-PC#fit-PC2
http://navigatrix.net/support.php

The screen is the killer! Need a source of low power 12v screens!

Looking forward to playing with a Fit-PC3 when it appears http://thetechjournal.com/electronics/computer/compulab-fit-pc3.xhtml