What we use.

[AnchorageGuy]

We have done some extensive cruising over the years and found electrical consumption a constant issue. We Have a 12-volt water maker and refrigeration on board. In addition we run power tools, recharge small batteries and use the microwave and TV/VCR quite a bit. We are finally to a place were we can just about meet all our demands. We have three solar panel fixed and wired for continuous use. We also have a wind generator mounted on the mizzen. A 100 amp alternator on the engine rounds out the charging system. We find that recharging the batteries are seldom a concern any more.

[Gisle]

Chuck Baier once whispered in the wind:
We find that recharging the batteries are seldom a concern any more.

Good to hear Chuck. I also plan on using solar and wind in addition to the engine based power system onboard today.

But I've been adviced to have a 24V circuit for the computer in addition to the 12V. +24V DC input power supplies have a broad range of input current, typically 18-32V. +12V DC input power supplies will very soon get below what the PC actually needs since a "normal" PC needs 12V, 5V and 3,3V from the power supply. What do you say about that guys?

[AnchorageGuy]

We have carried and used a laptop aboard for years and run it off the 12-volt adapter we bought at Radio Shack. It has never hiccuped until the Admiral hosed it down one day. We have used two different models. Compaq and HP. Just never had a problem. We run Nav programs with charts, Wefax and Airmail all the time. Good luck.

[Gisle]

I've also used my Dell laptop on several cruises connected to the 12V circuit, but I was thinking of having a stationary PC server with a 24V DC power supply onboard too.

The server will be the heart of the onboard "network" with large harddisks for storing images, DV-video, music, maps & charts, backups, complete website, etc

If parts fail it's much cheaper and easier to change them on a PC (have been building computers for the last 15 years) and I will of course have "double systems" for extra safety.

In the tropical marine enviroment I'll have on the boat things will happen to the computer system. Backup is essential.

The laptop is very vulnerable beeing up in the cockpit or saloon. The server will be stored away in a relatively dry place - I'm thinking of making a dry box with a cooling system for it

[AnchorageGuy]

Why set up a 24 volt system just for this? Why not hook up a small dedicated inverter just slightly larger that the system will need? It will run better and you can use it for other things on occasion.

[GordMay]

I agree with Chuck - thinking that a dedicated 24VDC system migh be needlessly complicated and expensive, and "big & heavy".

It would also be difficult to build-in power redundancy. "Small" inverters are cheap enough that you could have a back-up.

To further save expense, you could back up your "small" computer inverter with an even smaller one, that might only run the server (no periferals, like printers etc).

Regards,
Gord

[heerenleed]

I totally agree to the small inverter-theory. We already have a largeish inverter for the microwave, the central heating (as the shorepower networks in many marinas tend to get overcharged and therefore do not give you the 230 V you need (Europe), thus resulting in dirty diesel burners with all the accoring problems), the bread toaster and all other similar 'essentials'.

We still only use a laptop computer, but I agree these are vulnerable. We recently bought a new flat-screen TV-set (Philips 150 MT) which will double as computer monitor. Therefore, we can now install our large computer aboard. There is a locker under the chart table which is difficult to use, but it would be fine for the computer to live in. I think of taking out the door and build a dedicated box to fit into the opening. Any ideas how to keep it cool?
Or do I need to indeed?

Thanks for any suggestions.

[GordMay]

Peter:
Yes indeed, keep it cool.

Radio Shack (& others) sell little (3" & 4" Dia x 1" thick) 12VDC Computer Fans, and Grilles.

Cut (2) Holes, separated as far as practical, & install a Fan & Grille in one (blowing 'out'), and just a grille in the other (Supply Air).
Switch (& Fuse) the fan separately, as you may not always need it 'on'.
If the Fan is Mtd on an opening door, ensure you leave a loop in the wire, at the 'hinge side' - allowing the door to swing w/o pulling on the wire.

I'd probalbly just mount the CPU in the exist'g locker (no new box) - easier, more accessable, and larger volume of cooling air.

I've used this for my air-cooled Refer' Compressor (a lot warmer than a computer) to good effect. Minimal current draw - mimimal cost.

Regards,
Gord

[heerenleed]

The new box will be there for a reason: there are two hot-air ducts and 6 hot water tubes, all from our heating system, going also through this locker. As it was not used for anything important, this did not matter. In winter, the Compu might get too hot, that's why I think I must build the box. Also, the locker has an awkward shape against the hull, so if I make a box, it will be easier to tie the compu down in a seasafe manner.

The fans I know, and they're OK. However, going to the Radio Shack would make them a bit expensive for me......
cheers

[GordMay]

Peter:
Sorry, I should have paid attention to your location. Anyway, you seem to know the fans of which I speak.

Insulating the box may help keep some of that unwanted heat out.

However, you may need a larger fan than I suggested.

You will want at least 100 cfm of ventilation for each KW of heat (from air/water ducts/pipes etc.
100 cfm Air Flow = 47 L/S (Litres/Second)
1 KW Heat = 1000 Watts = 56.92 BTU/min.
The Computer itself will contribute about 250 Watts of heat (requiring 25cfm - 12L/S) .

Hope this helps, more than confuses.

Regards,
Gord