On Friday, September 10, 1999 at 3:00:00 AM UTC-4, DANKIRLIN wrote:
We had two of their next to the very smallest 10 cylinder engines aboard my frigate that drove our 500KW auxiliary generators. They were louder than all get out.
On Thu, 1 Feb 2018 06:40:17 -0800 (PST), snipped-for-privacy@gmail.com
wrote:
Be prepared to see Achates opposed piston multi-fuel engines in light
trucks within 5 years. they are 2 stroke turbo-compounded engines with
INSANE torque that fit into the same space as a common inline engine
like a cummins, or V8 like a Powerstroke.
Like the Kei cars in Japan? I've been seeing 440cc and 660cc engines
listed in Toyota Car and Truck shows lately.
I wonder if they could support generators for massive electric car
range extension. That might be the clincher for selling electric cars
to the masses, even though 90%+ of people don't need that kind of
range.
Rather than rebuilding my 4.7L Toyota engine next decade, should it
need it, I'd rather put the money into an electric motor and
batteries.
-
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet,
balance accounts, build a wall, set a bone, comfort the dying,
take orders, give orders, cooperate, act alone, solve equations,
analyze a new problem, pitch manure, program a computer, cook a
tasty meal, fight efficiently, die gallantly. Specialization is
for insects.
-Robert A. Heinlein
On Thursday, February 1, 2018 at 12:27:33 PM UTC-5, Larry Jaques wrote:
I've thought the same about my '99 Mazda as well, but maybe it's a little old...
As Al Gore said, "Electric cars aren't for everyone. They're just for about 90% of everyone." As range improves, I expect that number to reach well above 90%.
We don't have anywhere near the electric generating capacity to
support that.
...
I finally found a fairly decent and inexpensive battery monitor for
home energy projects:
(Amazon.com product link shortened)
It draws a little under 1 Watt for its own use, the current falling as
the voltage rises. With the display constantly lit it uses 35mA from
my 24V batteries.
The voltage error wandered as much as +/-50mV, 5 counts, as I stepped
up the input from 7.5V to 31V while measuring it with a 5-1/2 digit
Fluke. The current tracked my meters within +/-0.2A to 15A. It has a
200A 75mV shunt so an error of 0.1% of that isn't bad.
The downloadable manual is much better than the usual barely
comprehensible garble. Apparently long-pressing OK at CLR rezeroes the
current measurement. Otherwise the meter did what the manual said it
would.
Discharge current is positive, charge is negative, to make the graphic
gauge rise as the battery charges. Starting from reset on a full
battery, the Amp-Hour total increased as the battery discharged and
decreased as it recharged, passing through zero to negative when the
battery's charge current acceptance at 13.6V had fallen very low,
which is a good indication of a nearly full charge since the battery
doesn't waste charge as hydrogen if the charger limits the voltage
there. Exit lights and computer UPSs recharge lead batteries safely
but slowly indoors that way. OTOH the Watt-Hours total just increases
and after the initial discharge where it's useful it double-counts
energy in and back out.
While dedicated Lithium battery fuel gauges can self-calibrate this
one has to be told the battery's Amp-hour capacity. The capacity
indication appears to ignore the excess A-h charge when a lead-acid is
on float and starts the discharge percentage at your programmed value
of 100%. It looks like the A-h total will drift due to full charge
float current unless reset. I'm hoping the A-h total will remain
useful while the battery is partly discharged during an outage..
I tested it with full discharge cycles on an old 12V 18A-h AGM that
has deteriorated to 2.5 Amp-hours, and shallow cycles on my 100A-h
solar bank. The next week's weather forecast is too overcast for a
good test of solar recharging.
I didn't try the wireless connection because the USB one was reliable,
unlike the 30A + relay version of this device.
Previously I used separate unidirectional meters to measure Watt-hours
in and out. The problem is that a lead-acid discharges at a lower
voltage than it charges, which creates a difference between the
Wattage totals. Voltage would be a good indicator of state of charge
if I could leave the battery alone to settle for a few hours, but not
when I need to be using the power.
-jsw
Oh, I know that. We need to go modular with nuclear bases to support
the solar and wind intermittents. Lots of work has been done recently
to heat fluids with solar during the day for conversion at night to
electricity, but that will have to be done with excess solar.
Yeah, not bad. Digital DC Multimeter 0-90V 0-100A Voltmeter Ammeter
Power Capacity Time Meter | eBay https://is.gd/2uS2sC with shunt
board looks similar, with similar pricing. ($38 for the 2 pcs, lower
cap, higher price) The shunt is a separate piece on the DROK? It
appears that many Chinese vendors have embraced Amazon and the price
differences are minimal between Ebay an Amazon nowadays.
I picked up 5A, 20A, 50A, and 100A shunts for five a pop off Ebay so I
can avoid the errors, thinking they were worse. The Bayites we
discussed have since dropped in price a bit. It's about time for me
to start cutting holes in aluminum panels for their mounting.
Now that I've taken a year off to decompress, It's time ta git me
little solar farm up and running. It was nice not =having= to go out
into the cold mornings. Blackberries have taken over the East 40
again, though. Grrr...
Cool. Do you miss the Chinglish, though? :-/
Yes, charge current is a good indicator of SOC. UPS batteries seem to
last longer with their stingy system chargers, a good thing.
Hmm, not as useful.
These sounded smarter, at first, than their Bayite predecessors.
A test bed is a test bed, but <1/6 cap? <snort>
We're finally having dry and, if you can call mid-50s spring-like,
welcomed weather here. Bright sun and blue-skied afternoons, YES!
USB seems like a handy connector style. Standard USB? I found some
micro boards/connectors on Ebay a while back @ dirt cheap $, and I
have lots of std/micro cables around for my cell, Fire, and Kindle.
What was wrong with the relay version, circuitry or relay contact
failure?
Yeah, that sounds self-defeating, with the lead/lag A/V play, but now
you know.
True. What are you going to do with all that -power-, though? 2.5Ah!
Wow. <gd&r> That's enough to idle your laptop with the monitor off.
--
Stoop and you'll be stepped on;
stand tall and you'll be shot at.
I've heard that power wheelchair batteries may not last very long
because the user charges them only while in bed, so they rarely reach
full charge. The numbers are 1-2 years, compared to maybe 5 years for
the same battery in a golf cart that has longer to recharge. I know
from a job repairing medical equipment that the owners buy the
cheapest wet batteries when the original AGMs die. Supposedly that's a
consequence of the slow and fussy bureaucracy of government
healthcare.
My backup system could have the same charging problem. I hope a week
or so at partial discharge followed by a full equalizing charge
outdoors after the grid returns won't hurt the batteries much.
More importantly the VAC-1100A measures bidirectional current in the
ground lead of the supply that powers it, meaning that one current
sense input functions at as much as -37.5mV below the negative power
supply rail. The other +/- current meters that I have need an isolated
power supply that lets them float the negative-lead shunt up to their
+1.2V reference voltage. However the meter vendors don't offer a
suitable step-down switching power supply with an isolated output.
I've been using cheap surplus cell phone chargers with obsolete plugs,
which are fine for bench testing but not for running on DC during
power outages.
I've mentioned both this power supply problem and the poor/absent
manuals to Drok. Perhaps they listened.
It was the best one remaining from a bunch of second-hand exit light
AGMs I acquired around 2010. Its low capacity minimizes cycle times
while I check out the discharge testing hardware.
A flaky USB connection, and possibly intermittent measurement errors,
I only checked it briefly and may have misread the tiny display. It's
for unattended discharge capacity testing using the relay to
disconnect the battery at 10.5V, but those tests are time consuming
and way down on my to-do list.
I thought I could correct the Watt-hour difference with a simple
factor like 12/13, but the discharge voltage drop also varies with the
load current, SOC and battery age. For example after that old AGM
drops out at 10.5V @ 5A it recovers to about 12.1V. I pulled 5 A-h out
of it at lower current.
I have nominally 4 KWH of storage and a measured 300 Watts of 24V
charging power, slightly more than enough to keep up with the fridge,
two computers and the TV or to replace what the fridge used overnight.
.
-jsw
My neighbor found out that Medicare won't allow things to be recycled.
They will fund new items only. 2-month old hospital beds, 6 month old
3-wheeled electric scooters, etc. which are perfectly serviceable are
just tossed. That sickens me. Penny wise, pound foolish, as the
saying goes.
It shouldn't, but with _your_ batteries... LOL
That's good.
OK, it does what you need.
It's hard to stay attentive to long-term monitoring. I tend to set my
watch for a handful of minutes, then go check, resetting the watch
alarm each time.
Internal resistances play havoc with everything, triggering dropouts,
alarms, etc. Batteries can be perfectly good for most things, but try
to start a car with one and it will go TU in a heartbeat.
What do you make of these: 12 Volts Lead Acid Battery Desulfator
Assembled Kit | eBay https://is.gd/5cBjNg <$8 (120Hz pulse)
Whew! I'm glad it's not just that one battery. :-) What does that
4kwh work out to in ah? 166.7? Not a bad set. (Pair of group 27s?)
--
Stoop and you'll be stepped on;
stand tall and you'll be shot at.
The firms I worked for restored used medical equipment to a condition
Medicare would accept, as long as the customers' paperwork was fully
in order. And that was a major issue for many of the elderly. I know
some fell through the cracks but not why. Just doing my job here,
Ma'am.
As I've seen in my own affairs the system has little or no flexibility
to accomodate unforeseen exceptions, yet it's easily milked by those
who understand it. The government strives for fairness, economy and
value are completely foreign to Uncle Sugar. At least the industry pay
scale was nice.
-jsw
I think that has changed now, according to those two instances I saw.
Refurbs were just fine with our folks, who grew up with the Crash. I
think most folks today, other than Millennials, would accept them,
too.
But of course.
--
Stoop and you'll be stepped on;
stand tall and you'll be shot at.
The government paid big bucks for me to replace the seat, arm rests
and wheel bearings on a wheelchair at a factory-authorized dealership.
I don't know where the guy who sold refurbs out of an old barn
for -much- less got his parts, maybe China?
According to my neighbor, Medicare won't pay to rent or buy used items
for Medicare patients. The local rental place confirmed that when we
picked up the walker and wheelchair for her dad 4 years ago. He could
buy anything he wanted, but the gummint would only cover new items.
I'm wondering if this is a new thing.
So, the questions were
1) When were you were paid by the gov't to refurb stuff?
and
2) To whom was rented/sold? (not including the F/A dealer)
--
Stoop and you'll be stepped on;
stand tall and you'll be shot at.
1) I was never paid directly by the government, though I fixed VA
hospital equipment. The time frame was around 2005.
2) Individuals and facilities who needed it. I knew nothing about
billing beyond the time spent and parts replaced.
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