On 2017-03-15, Jim Wilkins wrote:
"DoN. Nichols" wrote in message
...
On 2017-03-14, Jim Wilkins wrote:
[ ... ]
Soldering works if done right. I use extra flexible silicone
'noodle'
wire
The white silicone insulated wire for HV? Nice flexible stuff.
Used to use it at work a lot.
This wi
https://www.amazon.com/12-Gauge-Sili.../dp/B0070RZXLW
The local RC hobby store and a discount store that sells car audio
cable carry larger sizes.
O.K. Not the same. The insulation is a lot thinner than the
wire gauge than what I was thinking about. It was about 16 Ga I think,
and was good up to at least 45 KV -- maybe a lot higher. We used it
with the voltage multipliers we made to power three-stage image
intensifiers. (A lot more current capacity than needed, but good HV
insulation.
I put Andersons on both ends and use it for
extension cables to charge batteries, then cut off short pieces as
needed.
O.K.
[ ... ]
I got a used 2-meter transceiver at a hamfest a while back
with soldered PowerPole connectors in it, and there was certainly
excess
solder in that job. And it was augmented by the intermittent 3AG
fuse.
(Clip on each end, and soft plastic snapped around it. It was only
once
I had replaced all of the soldered PowerPole connectors near it that
I
found the intermittent fuse. One cap was unglued, and the fuse
element
made contact most of the time, except if you shook the wires. :-)
The fuse cap glue melts if heated. That Signal Corps school made up
dummy fuses with large bus wire inserted but not touching both ends to
teach us to check fuses with an ohm meter.
Good idea.
One fuse had GOOD FUSE on a
slip of paper in it, another was blue (= blew). I recognized the
improbability of a 12 AWG wire element in a 3A fuse immediately since
I had a repertoire of similar sight gags and asked the intructor how
to do it, then we watched everyone else pull, examine and replace the
fuses and continue troubleshooting.
:-)
I wonder how they would have liked my 2.2K 2W carbon resistor
with color codes "Black, Black, Violet, Gold" :-) (RC42GF007J)
The wire in my Maytag's motor was similarly intermittent. I suspected
the timer contacts first and bypassed it with a wash/spin reversing
switch I'd been planning to install anyway but the problem remained.
When I removed the motor start switch board to check for burnt
contacts the wire broke free. Otherwise everything was still in good
condition, considering its 40 year age and that I found it dumped in
the woods. There were two of them and swapping rubber parts fixed this
one.
So -- both were found at the same time, and had the problem when
you got them?
The symptom of an open Run wire was that the motor drew about 22A when
it failed to start.
Hmmm ... series combination of the start cap and the run winding
resulting in quite low impedance at 60 Hz.
A good start blipped the analog Amprobe to 40A,
then dropped to 7A. The two-wire DVM resistance of the start winding
is 3.5 Ohms, the Normal and Gentle run windings are around 1 Ohm. The
Relative feature of my UT61E DVM was enough to cancel the lead
resistance to tell them apart.
Useful. My Fluke 27 can do that too, IIRC. But if I really
want good low resistance measurements, I use the rack-mount digital
multimeter from HP with 4-wire resistance capability. (Not very
portable, however. :-)
The automatic controls just interfere with using it with water heated
by alternate energy and poured in. Bypassing the timer and sensors
lets me wash with as little as 5 gallons heated on the wood stove,
though 8 is better. Water may be cheap but the electricity to heat it
isn't. The old non-computerized controls are easy to reconfigure by
moving the Fastons. The schematic is glued to the tub and is easier to
decipher than the relay-ladder-logic industrial controls I used to
design.
Did the schematic document the unused push-on tab functions too,
or did you have to trace out the switch?
There's this:
http://www.westmountainradio.com/pro...ts_id=PWRcrimp
It gives the contact retention force specs. At Mitre we had a jig
with
a tension gauge to test aircraft connector pins.
-jsw
O.K. Price is reasonable -- a different source (and slightly
different die shape) than mine (from QuickSilver, who tend to sell
at
the local hamfests).
IIRC some of my prewired larger Anderson's came from QuickSilver's
hamfest surplus trays.
http://www.near-fest.com/
I've picked up some pre-wired ones a bit bigger than I can crimp
with my present tools -- IIRC, something like 2-0 wire. (I've got the
crimp tools for AMP PDIG terminals -- hydraulicly powered -- all the way
up to 4-0 wire. :-) But the format of the crimp is wrong for the big
Anderson powerpole connectors. Those were not push-in contacts, but
rather unscrew the halves of the connector, insert the wires with
crimped terminals, and then screw together again.
I haven't found any other high-current connectors that are better
overall than Andersons despite their problems.
AMP makes some circular connectors with rectangular blade pins.
6-pin IIRC -- but not weather resistant, and certainly not genderless.
I used those to get power to servo motors from the servo amps on a
Bridgeport CNC conversion.)
The EC5 I bought to
make a cable for a Lithium jump starter doesn't disassemble as easily
and is gendered. I need a type where any cable will mate with any
other, sometimes in a Y to insert a current shunt. Most of my ammeters
are one-directional which is fine with power supplies but not
rechargeable batteries.
Hmm ... do you have the individual pin connectors for the
Andersons? You can dovetail any number together (and a number of colors)
to make weird connectors. And -- if you resist solvent-welding them,
you can split them easily to do things like passing one lead through a
current transformer at need.
The other readily available connector that survives the weather well
is the two pin "SAE" bullet connector for trailer wiring. The problem
is that it's electrically but not physically directional, which I
solve by painting a red + on a white patch on the positive side with
nail polish so I don't reverse the power from my solar panel when
plugging in the extension to charge vehicle batteries.
I remember some really weird weather resistant connectors we
used for plug-in lithium cells designed for Navy use, I believe. A soft
rubber pin (6mm or 1/4"diameter) with two or three metal colors molded
onto the wires, and the connector that they plugged into was open at
both ends, so as you slide it in, it pushes the water out. (I was
working for an Army R&D lab at the time, and I don't know how available
those connectors were to non-military users. Anyway -- not for the kind
of current that the PowerPoles can handle, anyway.
Enjoy,
DoN.
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