--
>From: "Phil Kane"
>To:
>Sent: Tuesday, October 08, 2013 5:16 PM
>Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
>
>
>> On 10/7/2013 3:44 PM, Neal Enault wrote:
>>
>>> To determine the effects of ambient temperature, one has to d
ay, October 08, 2013 7:17 PM
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
David,
I believe the same codes do apply since they are based on current, not
voltage.
Codes aside, do not take low voltage, high current sources lightly
(particularly batteries) because they are a very
David,
I believe the same codes do apply since they are based on current, not
voltage.
Codes aside, do not take low voltage, high current sources lightly
(particularly batteries) because they are a very large source of
energy. If shorted, molten metal spewing all over is not an
exaggeratio
t: Tuesday, October 08, 2013 5:16 PM
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
On 10/7/2013 3:44 PM, Neal Enault wrote:
To determine the effects of ambient temperature, one has to do some
not so accurate calculations or refer to a document like MIL-W-5088
which also provides guidanc
On 10/7/2013 3:44 PM, Neal Enault wrote:
> To determine the effects of ambient temperature, one has to do some
> not so accurate calculations or refer to a document like MIL-W-5088
> which also provides guidance for wire ratings in bundles and at
> various altitudes.
In the civilian/industrial w
Ed and all,
When calculating the voltage drop like this, you need to add the voltage
drop in the negative side wire as well as the positive side. The same
current flows on both sides, so the voltage drop must be calculated
using the length of both wires. This fact is often forgotten. .007
Another thing that states this is current ratings on switches (ever
look at the specs?).
Typical toggle switch may be rated 20A at 125vac and 10A at
250vac. Why? If the load resistance is the same then twice the
voltage will double the current. Heat dissipation of the switch is
the same fo
3:33 PM
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
So far nobody has mentioned insulation material. The rating of a cable has
little to do with melting the wire and mostly to do with melting or softening
the insulation which would create a shock and/ or fire hazard. The same
ubject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
OK Joe, You are correct. It has been a very long time since I have been
involved with heat related science issues. More current equals more heat
(for a given resistance) has been sufficient for me most of the time
without getting into the
OK Joe, You are correct. It has been a very long time since I have
been involved with heat related science issues. More current equals
more heat (for a given resistance) has been sufficient for me most of
the time without getting into the exact math.
It is good to know that some folks here
Fjeld
Sent: Monday, October 07, 2013 1:44 PM
To: Brad Blasing ; elecraft@mailman.qth.net
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
I didn't check your figures, but I agree with your understanding
except at
240 volts, tha
an.qth.net
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
I didn't check your figures, but I agree with your understanding
except at
240 volts, that same wire gauge would have twice the capacity.
__
Elecraft mai
I retract this. I have no excuse.
-Original Message-
From: Richard Fjeld
Sent: Monday, October 07, 2013 1:51 PM
To: Brad Blasing ; elecraft@mailman.qth.net
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
I better say 'twice the current carrying capacity'.
---
You are correct. I answered too quickly. I stand corrected.
Dick, n0ce
-Original Message-
From: Mark Bayern
Sent: Monday, October 07, 2013 1:50 PM
To: Richard Fjeld
Cc: Brad Blasing ; Elecraft Reflector
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
"I didn&#x
I better say 'twice the current carrying capacity'.
-Original Message-
From: Richard Fjeld
Sent: Monday, October 07, 2013 1:44 PM
To: Brad Blasing ; elecraft@mailman.qth.net
Subject: Re: [Elecraft] Elecraft Digest, Vol 114, Issue 11
I didn't check your figures, but I
>>"I didn't check your figures, but I agree with your understanding except at
>>240 volts, that same wire gauge would have twice the capacity.
"twice the capacity" What does that mean? Earlier you were talking
about current. At 240 volts the current carrying capacity of your wire
would be the
craft] Elecraft Digest, Vol 114, Issue 11
The math looks correct, but the analysis is wrong. The first statement
"rated for 20 amps at 120 volts" is wrong. A more correct statement would
be that a given wire size (12 gauge for example) is rated for 20 amps.
Voltage has nothing to do wi
The math looks correct, but the analysis is wrong. The first statement
"rated for 20 amps at 120 volts" is wrong. A more correct statement would
be that a given wire size (12 gauge for example) is rated for 20 amps.
Voltage has nothing to do with it. The amp rating of wire is based on gauge
only
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