Tacos Digest, Vol 18, Issue 11
gwbaumgartner at erols.com
Mon Sep 6 14:55:07 CDT 2004
Gents perhaps I can help since I do VANs, signal sites with generators,
solar and wind systems as part of my job(s).. And I love the work. I've
learned many ways NOT to do things with batteries and generators... MANY.
Mostly from fixing (redesign and rebuild) of failed systems or watching
other agencies suffer with their bad designs.
Rough guidance. Go with the 12 V idea it works almost always. Filter
power going to the 110 inverters for the computers so they don't trash the
entire 12 V Buss. (Keep the noise in the 110 V system) Shield, ground,
filter several times the 12 input to the inverter and the 110 output to the
computers) This is NOT a trivial problem.. Get it right or DO IT OVER
later. [voice of exp....here].
DO NOT go for specialized 12 V generator. Not efficient. Quite rare
(difficult to repair if failed) etc.Very heavy cable required to deliver
full power to the batteries and you will NEVER get them fully charged.
(13.8 to 14.2V.) NOT cheap if purchased either. BUT if you are going to
'go cheap' and build your own generators that IS the way to go since it is
really easy to built a 12 V DC generator [alternator with internal
regulator] and have it work. A little 1200 watt system is a monster.
(remember 100 + amps is required) A much easier way to go is to go with
110 V power converters (read large computer power supplies) wired in series
for 12 V. They have very clean outputs, perfect regulators, no noise, Will
run ALL your gear at 12 volts, are fairly small (even the 100 Amp ones) and
charge batteries nicely if you limit in rush charging currents. This system
also becomes a "free" UPS (no break in the 12 V supply) no matter what.
Shore power. Generator power, Solar (if you have a bit of cash for PVs), and
even wind if you have time to waste fooling with the things.
ISOLATE the starting battery always and build a cross connect relay
for starting just in case someone gets stupid anyway. Suggest a 3.5 kW
generator is plenty big for the AC and the rest of the stuff. 4.5 is nearly
an absolute max. Personally I love the Honda 3.0 kW super quiet generator
(model # EU-3000) and I force systems down to a 3.0 max load if at all
possible. AC if it needs to be replaced can be an 8000 or 10000 BTU and
easily be run by a smaller gen than the monster in Frank's lab. On the
other hand the monster IS free. It will roar like a beast and drink
somewhat more gas but if it works you are very unlikely to over load it.
You guys call it. Personally I think I'd go with a smaller gen as a spare
no matter what we do. The beast will eventually quit and being without a
gen when you really need one is not funny. Fixing regulators, and burned
exciter windings in the field is usually impossible. BRING a SPARE of
anything important that can't be wired around. ACTUALLY built your system
so you CAN wire around anything...including the power distribution panel and
any breaker. Usually a simple by pass with extension cords, plugs strips
etc will do.
This stuff is always fun. Will help for food and drink. (Coors, Bud
----- Original Message -----
From: <tacos-request at amrad.org>
To: <tacos at amrad.org>
Sent: Monday, August 30, 2004 1:00 PM
Subject: Tacos Digest, Vol 18, Issue 11
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> Today's Topics:
> 1. AMRAD van work day (Frank Gentges)
> 2. Re: AMRAD van work day (Andre Kesteloot)
> Message: 1
> Date: Sun, 29 Aug 2004 19:12:36 -0400
> From: Frank Gentges <fgentges at mindspring.com>
> Subject: AMRAD van work day
> To: Tacos <tacos at amrad.org>
> Message-ID: <413262E4.10806 at mindspring.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> We had a beautiful day to work on the AMRAD van. It got a little hot
> but some good work got finished. Paul Rinalso is providing some ICOM
> radio gear for HF, 2M and 440.
> Paul mapped out the interior. We can use his drawings to plan out
> changes for our future use.
> We finished remounting the ladder which was loose and seemed dangerous
> when we obtained the van. Now it is sturdy and it feels safe to climb
> up to the roof.
> The hinge on the rear access door for the air conditioner was replaced.
> The hinge was rusting as it was not well plated originally. Andre'
> provided a replacement stainless steel piano hinge . I cut it down from
> its 6 foot length. and it mounted in the same holes as the old hinge. A
> tip of the AMRAD hat to Andre' and his now hinge less piano.
> We also replaced the drivers side door handle. Without it we had to
> roll down the window to get a grip on the door and get it closed.
> We did not get any expertise on the exhaust system noise so I will take
> the van to an exhaust shop for repairs. It is a bit more than I can
> repair on my own.
> Some thinking.....
> Most modern ham gear including the one provided by Paul run directly on
> 12 volts. The use of 120 vac for this gear seems superfluous and direct
> 12 volt connection makes good sense.
> Desktop computers run on 120vac. The power drain is not that great and
> the computers can be run off of a 12v to 120v inverter. Monitors are
> similar. Laptop/Notebook computers are a mixed bag but the amount of
> 120v power is not that great for them so inverters can handle those also.
> The RV air conditioner installed in the van is a 13500 BTU unit but
> built in 1986. It requires 16 amps of 120vac power It has a separate
> condenser and evaporator unit with snap on coupling for the
> refrigerant. I suspect the refrigerant has leaked down and will have to
> be recharged. We may need to replace this with a more modern window
> unit adapted to the van if we want air conditioning.
> If we disregard the air conditioning, we could power the van for
> indefinite periods with a small 12 volt portable generator that is
> configured to act as a battery charger. Presently, the van has 5 deep
> cycle marine batteries in parallel. The generator needs to keep us from
> drawing down the batteries during long term use but would not have to
> run continuously. Anybody know what kind of options are out there for
> such a generator?
> A small 120vac portable generator can be used to power the air
> conditioner and other comfort needs in a supporting camp site we would
> deploy with the van.
> At this point the 7kw generator may be too much to install in the van.
> If we do not use it, we can cut down the generator compartment in the
> van to make more room available inside the van. This compartment is huge.
> We discovered that the passenger side seat can be turned 180 degrees to
> face rearward. We can build a drop down desk so this could become a
> third operating position.
> We are investigating use of Direcway satellite Internet connection. I
> think we have most of the details worked out and have a used unit
> donated to us..
> We are looking at a concept of making a satellite Internet connection
> when we deploy and then providing a LAN with a lot of it being
> wireless. We need to think about what we could do with this in a
> disaster. Health and Welfare email would seem to be quite possible.
> Details still need to be worked out. Paul is thinking of using 2.4 GHz
> amateur frequencies for some of the connections that would include the
> public safety people.
> Its getting a bit long but a lot is happening in act and thought.
> Frank K0BRA
> Message: 2
> Date: Sun, 29 Aug 2004 21:02:49 -0400
> From: Andre Kesteloot <andre.kesteloot at verizon.net>
> Subject: Re: AMRAD van work day
> To: Frank Gentges <fgentges at mindspring.com>
> Cc: Tacos <tacos at amrad.org>
> Message-ID: <41327CB9.3060309 at verizon.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> Frank Gentges wrote:
> > The hinge on the rear access door for the air conditioner was
> > replaced. The hinge was rusting as it was not well plated
> > originally. Andre' provided a replacement stainless steel piano hinge
> > . I cut it down from its 6 foot length. and it mounted in the same
> > holes as the old hinge. A tip of the AMRAD hat to Andre' and his now
> > hinge less piano.
> By the way,
> is anyone interested in a grand piano, in perfect shape, except for a
> minor detail ?
> Tacos mailing list
> Tacos at amrad.org
> End of Tacos Digest, Vol 18, Issue 11
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