110v ac to 12v dc power supply

Take a look at Astron. They still mfg a full line. I've not used their more recent equipment, but had good luck years ago running 12V mobile communications equipment at fixed locations on Astron power supplies.

Bob, Thank you. Astron has all the choices at:

http://www.astroncorp.com/catalog.asp

Do you have a suggestion as to a linear or a switching power supply for this usage? Brian

I am copying below a suggestion from Bob on another forum which occurs to me is an elegant solution:

......." I have mixed feelings on this, but I'm still considering it for my boat....You could place a battery of some sort up high. This would not require a thick DC cable to keep charged. But it would provide "extra" current when required, like for VHF transmit. In an emergency, if you designed it right, you could also isolate it from you house battery if they failed or flooded. Then your VHF would still work...I'm still thinking on this, there are some other redeeming qualities, including some isolation from engine start spikes. But I'm still not 100% sold. Something for you to consider anyway."

I do not know why Bob is not 100% yet but it occurs that this provides unique advantages.

I am dropping the 110v to 12v idea to pursue this. Ben, could you weigh in also?
Thanks, Brian

I'm pretty dim on power issues, Brian, but I think that the NMEA installation guidelines have a fair bit on dedicated navigation/communications batteries, and it may be a requirement on some commercial vessels.

I don't know enough about the newer switching power supply designs to answer your first question. I think if you described the application to the Astron sales guys, they would be able to tell you more. Especially your concern for energy efficiency.

If you are running a modified sine wave inverter to power the power supply, be sure to tell them that, it may well have an impact on what they tell you.

The battery is probably a better choice. For this application, I'd choose an AGM battery, assuming you have lead acid or AGM house batteries.

I lost the original link, but Victron Energy has a great paper on energy management, especially the selection, care and feeding of batteries. You can find it on my website for another week or so at:

http://server.ebaugh.net/Defever/Victron-White-Paper-Energy.pdf

Regards, Bob

The source for the free Victron Energy "Energy Unlimited" book is here:

http://www.victronenergy.com/orderbook/

Regards,
Kees

I'd use a Victron or Mastervolt DC/DC converter set up in Battery Charge mode between the two batteries btw., that way you don't need to throw any switches when you main battery is out and it prevents the charge going into the main battery from over charging the separate VHF battery.

Many thanks for all the helpful input.
After much consideration I have decided to go with a small sealed battery for my flybridge instruments 12V power. The battery will be charged by both the house 12V supply with a Guest inline isolator and also a BatteryMinder 2/4/8 amp charger/maintainer plugged into the 110 V supply up there. This solution provides a 'buffered' power source with two ways to keep the battery up. All this proved to be lower cost than a Newmar power supply which is the only supply I could get blessed [privately] by my Simrad expert. Please advise if I have overlooked anything.
Brian

Here are some links to some of the products referenced previously. Brian

The pulse charger/maintainer I selected is the Batteryminder model #12248 which is described here:
http://www.batteryminders.com/batterych ... 16133.html
My choice was primarily based on the charging rate as I still do not know how high my total current will be when I am finished adding components.
I will have the house 12V supply available to the battery via a Guest gst-2501 battery isolator.
The battery is an Enersys/Yuasa NP18-12 Battery found here:
http://www.pacificbattery.com/np18-12.html