I see you got plenty of answers about the APPs, Bill. You will need to
provide your own suitable connectors for the power supply end of the cable.

You mention having high-capacity batteries and a 70-amp Astron supply. It
sounds like you have experience with high-current supplies and understand
how dangerous they can be, but there are a lot of readers here who may not
have that background. 

I mention it because many Hams think 13.8 VDC is safe to handle. It's *NOT*.
It's not the voltage, of course, but the current. A short often produces a
flash of molten metal that may continue for a while if the resistance is
enough to avoid tripping a breaker or crowbar circuit.

It can take off a finger or a hand, or very severely injure a person in an
instant should a ring or watch band get across the supply line, immediately
transformed by the current into red-hot metal burning its way through flesh.
In my days working in the field as an aircraft radio/radar tech I knew some
who were missing fingers because they neglected to take off a wedding band
when working. It's not a nice way to lose a hand or finger. It's not always
quick. It can take a while, with the ring or watch band welded solidly to
the terminals by the current as the hot metal eats its way through a finger
or wrist. 

I've seen tempered steel screwdrivers literally explode into a spray of
molten metal blobs when dropped across a high-current, low-voltage supply -
blobs of molten steel that splatter the face and eyes of the unwary worker
not wearing protective gear. Less severe shorts can set wiring, and the
shack, on fire in short order, all without opening a breaker or tripping the
crowbar protective circuit in the power supply. Even a more moderate 35 Amp
supply can start a fire or cause a severe burn under the right conditions. 

Working on shipboard and aircraft systems using 12 to 28 VDC at high
currents, I've learned to treat such supplies with the same respect I do a
3KV high-voltage supply. The concerns and procedures needed to be safe are
different, but either a high voltage or a low-voltage, high-current supply
is dangerous in its own way. 

I use soldered-on ring terminals on my Astron supplies that provide large,
low-resistance contact areas with the lugs and which cannot be pulled loose
without physically breaking the wire, and I make very sure there are no
metallic objects (cabinets, connectors, other equipment, etc.) located where
they might be accidentally moved and make contact with exposed supply
terminals anywhere. And then I make sure the terminals on my power supply
(and anywhere else) are carefully covered and insulated from accidental
contact, just in case. 

Ron AC7AC 


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