REFLECTOR:Exhaust Thermocouple

[Wayne Lanza]

--Apple-Mail-2-7777837
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain;
	charset=ISO-8859-1;
	format=flowed

Typically you will see a jump to maximum/full scale when a thermocouple=20=

goes open.
You will get a somewhat believable reading during heat up but at a=20
certain point the
bimetal junction of the thermocouple will stress and open - only to=20
close again when cool...
I have seen this a lot with with the thin, small diameter probes (used=20=

by VMI & JPI). To fix the
problem use a quality, ungrounded probe. The best source for good=20
thermocouples is
Electronics International - they make, calibrate and guarantee their=20
own (type K) probes.

Hope this helps,
Wayne Lanza
_______________________________________________________________________

On Monday, November 10, 2003, at 10:00 AM, HYTEC45@aol.com wrote:

> I have a Vision 1000 and had a cylinder (#3) take a jump in indicated=20=

> EGT after 20/25min. of operation a flight back.=A0 Every thing was =
fine=20
> with all jugs showing 1350, when #3 jumped to 1500/25.=A0 I don't =
really=20
> think a cylinder can get that high as mine seem to stumble around=20
> 1425.=A0 My thermocouplers are mounted 2" from the flange.=A0 When I=20=

> pulled power during the approach and things cooled off, the=20
> thermocoupler seemed to read normal along with the others.=A0 A friend=20=

> with a Berkut said he had a thermocoupler go bad and they will either=20=

> read nothing, or go full scale to 1500.
>
> Just passing that on, but I think someone mentioned an alternate=20
> source for the exhaust thermocouplers.=A0 Any one know before I order=20=

> one from Vision?
>
> Thanks
> TEC
>

--Apple-Mail-2-7777837
Content-Transfer-Encoding: quoted-printable
Content-Type: text/enriched;
	charset=ISO-8859-1

Typically you will see a jump to maximum/full scale when a
thermocouple goes open.

You will get a somewhat believable reading during heat up but at a
certain point the=20

bimetal junction of the thermocouple will stress and open - only to
close again when cool...

I have seen this a lot with with the thin, small diameter probes (used
by VMI & JPI). To fix the

problem use a quality, ungrounded probe. The best source for good
thermocouples is

Electronics International - they make, calibrate and guarantee their
own (type K) probes.


Hope this helps,

Wayne Lanza

_______________________________________________________________________


On Monday, November 10, 2003, at 10:00 AM, HYTEC45@aol.com wrote:


<excerpt><fontfamily><param>Arial</param><smaller>I have a Vision 1000
and had a cylinder (#3) take a jump in indicated EGT after 20/25min.
of operation a flight back.=A0 Every thing was fine with all jugs
showing 1350, when #3 jumped to 1500/25.=A0 I don't really think a
cylinder can get that high as mine seem to stumble around 1425.=A0 My
thermocouplers are mounted 2" from the flange.=A0 When I pulled power
during the approach and things cooled off, the thermocoupler seemed to
read normal along with the others.=A0 A friend with a Berkut said he had
a thermocoupler go bad and they will either read nothing, or go full
scale to 1500.


Just passing that on, but I think someone mentioned an alternate
source for the exhaust thermocouplers.=A0 Any one know before I order
one from Vision?


Thanks

TEC</smaller></fontfamily>


</excerpt>=

--Apple-Mail-2-7777837--