Today's Message Index:
----------------------
1. 04:05 AM - Re: Weak Starter (William Greenley)
2. 06:07 AM - Re: Weak Starter (John Morgensen)
3. 10:13 AM - Re: Weak Starter (David Lloyd)
4. 11:22 AM - Re: Weak Starter (John Morgensen)
5. 12:44 PM - Re: Weak Starter (Bill Watson)
6. 04:04 PM - Circuit breaker question (Justin Jones)
7. 05:17 PM - Re: Circuit breaker question (Charlie England)
8. 06:04 PM - Re: Circuit breaker question (Justin Jones)
9. 07:21 PM - Re: Circuit breaker question (Charlie England)
10. 07:47 PM - Re: Circuit breaker question (Justin Jones)
11. 10:34 PM - Re: Circuit breaker question (Jeff Luckey)
Message 1
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I agree, I had these same issues on my 172 and it was the master relay, the starter
relay was fine. I replaced both as they were both of the same vintage. Starting
problems gone.
Bill
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Kelly McMullen
Sent: Sunday, December 06, 2015 9:41 PM
Subject: Re: AeroElectric-List: Weak Starter
--> <kellym@aviating.com>
You probably need to replace both starter relay and master relay.
Download Skytec's troubleshooting chart and follow it carefully.
On 12/6/2015 5:15 PM, John Morgensen wrote:
> <john@morgensen.com>
>
> My Skytec starter barely turns over an IO320.
>
> I measured:
>
> Battery 13.12 volts.
> "On" side of master contactor to airframe ground 12.25 volts.
> "On" side of starter contactor to airframe ground while cranking 8.6
> to 9.0 volts.
> Big wire on starter to airframe ground while cranking is 8.6 volts or
> less.
>
> All this was done with a genuine Harbor Freight $4.00 digital meter. I
> believe that this points to the starter contactor as the culprit.
> Correct?
>
> john
>
>
Message 2
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| Subject: | Re: Weak Starter |
Thanks for all of the replies.
Skytec's troubleshooting chart says that the starter needs to see 10+
volts. I will be replacing both relays.
john
On 12/6/2015 6:41 PM, Kelly McMullen wrote:
> <kellym@aviating.com>
>
> You probably need to replace both starter relay and master relay.
> Download Skytec's troubleshooting chart and follow it carefully.
>
> On 12/6/2015 5:15 PM, John Morgensen wrote:
>> <john@morgensen.com>
>>
>> My Skytec starter barely turns over an IO320.
>>
>> I measured:
>>
>> Battery 13.12 volts.
>> "On" side of master contactor to airframe ground 12.25 volts.
>> "On" side of starter contactor to airframe ground while cranking 8.6
>> to 9.0 volts.
>> Big wire on starter to airframe ground while cranking is 8.6 volts or
>> less.
>>
>> All this was done with a genuine Harbor Freight $4.00 digital meter.
>> I believe that this points to the starter contactor as the culprit.
>> Correct?
>>
>> john
>>
>>
>>
>>
>>
>>
>
>
Message 3
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| Subject: | Re: Weak Starter |
John,
A problem like you are seeing can also be caused by an "aged" main battery.
The battery V measures fine with no load, may also measure fine with just a
buss current load, but, when it sees a "starter" type current load (200 -
300 amps), it slumps badly. Usually caused by a cell or two that are too
aged to produce the amps needed.
Only answer is to install a new battery and keep it fresh by keeping a low
current "maintainer" style charger on it during hangar periods.
David
____________________________________________________________
----- Original Message -----
From: "John Morgensen" <john@morgensen.com>
Sent: Monday, December 07, 2015 6:06 AM
Subject: Re: AeroElectric-List: Weak Starter
> <john@morgensen.com>
>
> Thanks for all of the replies.
>
> Skytec's troubleshooting chart says that the starter needs to see 10+
> volts. I will be replacing both relays.
>
> john
>
> On 12/6/2015 6:41 PM, Kelly McMullen wrote:
>> <kellym@aviating.com>
>>
>> You probably need to replace both starter relay and master relay.
>> Download Skytec's troubleshooting chart and follow it carefully.
>>
>> On 12/6/2015 5:15 PM, John Morgensen wrote:
>>> <john@morgensen.com>
>>>
>>> My Skytec starter barely turns over an IO320.
>>>
>>> I measured:
>>>
>>> Battery 13.12 volts.
>>> "On" side of master contactor to airframe ground 12.25 volts.
>>> "On" side of starter contactor to airframe ground while cranking 8.6 to
>>> 9.0 volts.
>>> Big wire on starter to airframe ground while cranking is 8.6 volts or
>>> less.
>>>
>>> All this was done with a genuine Harbor Freight $4.00 digital meter. I
>>> believe that this points to the starter contactor as the culprit.
>>> Correct?
>>>
>>> john
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>
>
>
---
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Message 4
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| Subject: | Re: Weak Starter |
David,
Be careful with "maintainer" style chargers and Odyssey PC680 batteries.
Notice that the warranty can be voided:
C. The warranty does not cover a Battery that is damaged or destroyed as
a result of one for more of the
following:
Willful abuse, misuse, physical damage, neglect or if the top decorative
cover has been removed.
Natural forces such as wind, lightning, hail; damage due to fire,
collision, explosion, vandalism, theft,
penetration or opening of the Battery case in any manner.
Overcharging, undercharging, charging or installing in reverse polarity,
improper maintenance, allowing
the Battery to be deeply discharged via a parasitic load or mishandling
of the Battery such as but not
limited to using the terminals for lifting or carrying the
Battery._Trickle chargers that do not have a regulated __
__trickle charge voltage between 13.5V and 13.8V (no lower than 13.5V
and no higher than 13.8V) will cause __
__early failure of the Battery. _Use of such chargers with the Battery
will also void the Batterys warranty. For
applications where an alternator is present, the alternator must deliver
between 14.0V and 14.7V when
measured at the Batterys terminals. Alternators that do not have a
regulated charge between 14.0V and
14.7V (no lower than 14.0V and no higher than 14.7V) will cause early
failure of the Battery. Use of such
alternators with the Battery will also void the Batterys warranty
I thought I was doing the right thing by religiously using a quality
Battery Minder but it destroyed the battery. They use to publish a list
of unacceptable chargers but I can't find it on their web site any more.
john
On 12/7/2015 10:11 AM, David Lloyd wrote:
> <skywagon@charter.net>
>
> John,
> A problem like you are seeing can also be caused by an "aged" main
> battery.
> The battery V measures fine with no load, may also measure fine with
> just a buss current load, but, when it sees a "starter" type current
> load (200 - 300 amps), it slumps badly. Usually caused by a cell or
> two that are too aged to produce the amps needed.
> Only answer is to install a new battery and keep it fresh by keeping a
> low current "maintainer" style charger on it during hangar periods.
> David
>
> ____________________________________________________________
>
>
> ----- Original Message ----- From: "John Morgensen" <john@morgensen.com>
> To: <aeroelectric-list@matronics.com>
> Sent: Monday, December 07, 2015 6:06 AM
> Subject: Re: AeroElectric-List: Weak Starter
>
>
>> <john@morgensen.com>
>>
>> Thanks for all of the replies.
>>
>> Skytec's troubleshooting chart says that the starter needs to see 10+
>> volts. I will be replacing both relays.
>>
>> john
>>
>> On 12/6/2015 6:41 PM, Kelly McMullen wrote:
>>> <kellym@aviating.com>
>>>
>>> You probably need to replace both starter relay and master relay.
>>> Download Skytec's troubleshooting chart and follow it carefully.
>>>
>>> On 12/6/2015 5:15 PM, John Morgensen wrote:
>>>> <john@morgensen.com>
>>>>
>>>> My Skytec starter barely turns over an IO320.
>>>>
>>>> I measured:
>>>>
>>>> Battery 13.12 volts.
>>>> "On" side of master contactor to airframe ground 12.25 volts.
>>>> "On" side of starter contactor to airframe ground while cranking
>>>> 8.6 to 9.0 volts.
>>>> Big wire on starter to airframe ground while cranking is 8.6 volts
>>>> or less.
>>>>
>>>> All this was done with a genuine Harbor Freight $4.00 digital
>>>> meter. I believe that this points to the starter contactor as the
>>>> culprit. Correct?
>>>>
>>>> john
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
>
Message 5
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| Subject: | Re: Weak Starter |
I would second the points made below in John's post.
Over the past 9 years I've managed to abuse and slowly kill a number of
PC680s in a variety of ways. Simply reading and FOLLOWING the
guidelines documented in their Owner's Manual, including the fine print
of the Warranty, will avoid ALL of the problems I've experienced.
Why didn't I? Well, since I grew up charging batteries from early 60s
electric tooth brushes that could barely handle a full set of teeth, to
gliders, boats, cars and 50 years of RC aircraft, I must know what I'm
doing. So I've taken the time to rediscover and learn anew all that was
already known about Odessy's AGM line of batteries. I'm almost done
with my studies...
Regarding trickle chargers, according to the Manual, "..there is no need
to trickle or float charge during winter months." It continues, "It can
be stored for 2 years or more below 77F." If you insist, see Warranty
notes reproduced below. If you do have some kind of parasitic load on
the battery during storage (I had that), get it fully charged (you must
start there) , apply a trickle charger that can produce the regulated
voltage (I didn't), then for good measure, fully charge it before using
it. Better, just disconnect the load and save the cost of the trickle
charger.... or $150 lets you start the learning process from the
beginning again.
Just to repeat, I've found the information in Odyssey's Owner's Manual
to be complete and accurate in every way. The only thing that upsets me
is that they cost $150 a copy, but at least it comes with a fresh battery.
Bill "content to remain ignorant about Lithium technologies and to
simply enjoy their performance" Watson
On 12/7/2015 2:21 PM, John Morgensen wrote:
> David,
> Be careful with "maintainer" style chargers and Odyssey PC680
> batteries. Notice that the warranty can be voided:
>
> C. The warranty does not cover a Battery that is damaged or destroyed
> as a result of one for more of the
> following:
>
> Willful abuse, misuse, physical damage, neglect or if the top
> decorative cover has been removed.
>
> Natural forces such as wind, lightning, hail; damage due to fire,
> collision, explosion, vandalism, theft,
> penetration or opening of the Battery case in any manner.
>
> Overcharging, undercharging, charging or installing in reverse
> polarity, improper maintenance, allowing
> the Battery to be deeply discharged via a parasitic load or
> mishandling of the Battery such as but not
> limited to using the terminals for lifting or carrying the
> Battery._Trickle chargers that do not have a regulated __
> __trickle charge voltage between 13.5V and 13.8V (no lower than 13.5V
> and no higher than 13.8V) will cause __
> __early failure of the Battery. _Use of such chargers with the Battery
> will also void the Batterys warranty. For
> applications where an alternator is present, the alternator must
> deliver between 14.0V and 14.7V when
> measured at the Batterys terminals. Alternators that do not have a
> regulated charge between 14.0V and
> 14.7V (no lower than 14.0V and no higher than 14.7V) will cause early
> failure of the Battery. Use of such
> alternators with the Battery will also void the Batterys warranty
>
> I thought I was doing the right thing by religiously using a quality
> Battery Minder but it destroyed the battery. They use to publish a
> list of unacceptable chargers but I can't find it on their web site
> any more.
>
> john
>
>
> On 12/7/2015 10:11 AM, David Lloyd wrote:
>> <skywagon@charter.net>
>>
>> John,
>> A problem like you are seeing can also be caused by an "aged" main
>> battery.
>> The battery V measures fine with no load, may also measure fine with
>> just a buss current load, but, when it sees a "starter" type current
>> load (200 - 300 amps), it slumps badly. Usually caused by a cell or
>> two that are too aged to produce the amps needed.
>> Only answer is to install a new battery and keep it fresh by keeping
>> a low current "maintainer" style charger on it during hangar periods.
>> David
>>
>> ____________________________________________________________
>>
>>
>> ----- Original Message ----- From: "John Morgensen" <john@morgensen.com>
>> To: <aeroelectric-list@matronics.com>
>> Sent: Monday, December 07, 2015 6:06 AM
>> Subject: Re: AeroElectric-List: Weak Starter
>>
>>
>>> <john@morgensen.com>
>>>
>>> Thanks for all of the replies.
>>>
>>> Skytec's troubleshooting chart says that the starter needs to see
>>> 10+ volts. I will be replacing both relays.
>>>
>>> john
>>>
>>> On 12/6/2015 6:41 PM, Kelly McMullen wrote:
>>>> <kellym@aviating.com>
>>>>
>>>> You probably need to replace both starter relay and master relay.
>>>> Download Skytec's troubleshooting chart and follow it carefully.
>>>>
>>>> On 12/6/2015 5:15 PM, John Morgensen wrote:
>>>>> <john@morgensen.com>
>>>>>
>>>>> My Skytec starter barely turns over an IO320.
>>>>>
>>>>> I measured:
>>>>>
>>>>> Battery 13.12 volts.
>>>>> "On" side of master contactor to airframe ground 12.25 volts.
>>>>> "On" side of starter contactor to airframe ground while cranking
>>>>> 8.6 to 9.0 volts.
>>>>> Big wire on starter to airframe ground while cranking is 8.6 volts
>>>>> or less.
>>>>>
>>>>> All this was done with a genuine Harbor Freight $4.00 digital
>>>>> meter. I believe that this points to the starter contactor as the
>>>>> culprit. Correct?
>>>>>
>>>>> john
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>> ---
>> This email has been checked for viruses by Avast antivirus software.
>> https://www.avast.com/antivirus
>>
>>
>>
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>
> No virus found in this message.
> Checked by AVG - www.avg.com <http://www.avg.com>
>
Message 6
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| Subject: | Circuit breaker question |
Hangar talk with a neighbor. He is designing a circuit using 4awg wire for his
alternator. He asked me if he could use 2 - 50A circuit breakers wired in Parallel
for this purpose instead of a single 100A breaker. Chapter 11 in AC 43 says
to use a 100A breaker or a 70A fuse for 4AWG wire. I suggested the use of
a 70A ANL fuse, but wasnt sure what the answer is to the CB question he had.
Any insight?
Justin
Message 7
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| Subject: | Re: Circuit breaker question |
On 12/7/2015 6:02 PM, Justin Jones wrote:
>
> Hangar talk with a neighbor. He is designing a circuit using 4awg wire for his
alternator. He asked me if he could use 2 - 50A circuit breakers wired in Parallel
for this purpose instead of a single 100A breaker. Chapter 11 in AC 43
says to use a 100A breaker or a 70A fuse for 4AWG wire. I suggested the use of
a 70A ANL fuse, but wasnt sure what the answer is to the CB question he had.
>
> Any insight?
>
> Justin
No. (To using 2 breakers in parallel.)
And that's a weird recommendation, too, unless the fuse mentioned is a
special long-time-constant 'slow blow' type fuse. A breaker would take a
lot longer to trip than a standard fuse of the same value; going 30A
higher with the breaker *and* having slower response sounds really strange.
Buying 2 50 A a/c breakers (or even one 100 A breaker) would just kill
my (wallet's) soul. A fuse-able link would be lighter, take no panel
space, a *lot* cheaper, and if soldered in place, a *lot* more reliable
than a breaker (no joints to corrode or contacts to fail). If it's
properly sized, it shouldn't need attention for the life of the a/c,
unlike a CB.
FWIW,
Charlie
Message 8
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| Subject: | Re: Circuit breaker question |
The ANL fuse suggestion came from Bob's Z diagrams (note 10)
> On Dec 7, 2015, at 16:16, Charlie England <ceengland7@gmail.com> wrote:
>
>
>> On 12/7/2015 6:02 PM, Justin Jones wrote:
>>
>> Hangar talk with a neighbor. He is designing a circuit using 4awg wire for his
alternator. He asked me if he could use 2 - 50A circuit breakers wired in
Parallel for this purpose instead of a single 100A breaker. Chapter 11 in AC 43
says to use a 100A breaker or a 70A fuse for 4AWG wire. I suggested the use
of a 70A ANL fuse, but wasnt sure what the answer is to the CB question he had.
>>
>> Any insight?
>>
>> Justin
> No. (To using 2 breakers in parallel.)
>
> And that's a weird recommendation, too, unless the fuse mentioned is a special
long-time-constant 'slow blow' type fuse. A breaker would take a lot longer
to trip than a standard fuse of the same value; going 30A higher with the breaker
*and* having slower response sounds really strange.
>
> Buying 2 50 A a/c breakers (or even one 100 A breaker) would just kill my (wallet's)
soul. A fuse-able link would be lighter, take no panel space, a *lot*
cheaper, and if soldered in place, a *lot* more reliable than a breaker (no joints
to corrode or contacts to fail). If it's properly sized, it shouldn't need
attention for the life of the a/c, unlike a CB.
>
> FWIW,
>
> Charlie
>
>
>
>
>
Message 9
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| Subject: | Re: Circuit breaker question |
ANL would obviously be fine, but I was assuming that AC43 wouldn't be
recommending ANL fuses. Even with ANL, it's still weird that they would
equate a 100A breaker to a 70A fuse.
On 12/7/2015 8:02 PM, Justin Jones wrote:
>
> The ANL fuse suggestion came from Bob's Z diagrams (note 10)
>
>
>
>> On Dec 7, 2015, at 16:16, Charlie England <ceengland7@gmail.com> wrote:
>>
>>
>>> On 12/7/2015 6:02 PM, Justin Jones wrote:
>>>
>>> Hangar talk with a neighbor. He is designing a circuit using 4awg wire for
his alternator. He asked me if he could use 2 - 50A circuit breakers wired in
Parallel for this purpose instead of a single 100A breaker. Chapter 11 in AC
43 says to use a 100A breaker or a 70A fuse for 4AWG wire. I suggested the use
of a 70A ANL fuse, but wasnt sure what the answer is to the CB question he had.
>>>
>>> Any insight?
>>>
>>> Justin
>> No. (To using 2 breakers in parallel.)
>>
>> And that's a weird recommendation, too, unless the fuse mentioned is a special
long-time-constant 'slow blow' type fuse. A breaker would take a lot longer
to trip than a standard fuse of the same value; going 30A higher with the breaker
*and* having slower response sounds really strange.
>>
>> Buying 2 50 A a/c breakers (or even one 100 A breaker) would just kill my (wallet's)
soul. A fuse-able link would be lighter, take no panel space, a *lot*
cheaper, and if soldered in place, a *lot* more reliable than a breaker (no
joints to corrode or contacts to fail). If it's properly sized, it shouldn't need
attention for the life of the a/c, unlike a CB.
>>
>> FWIW,
>>
>> Charlie
>>
>>
>>
>>
>>
Message 10
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| Subject: | Re: Circuit breaker question |
I thought it was strange too. It's table 11-3 on page 11-15 in chapter 11 of
AC 43.13.1B
> On Dec 7, 2015, at 18:19, Charlie England <ceengland7@gmail.com> wrote:
>
.com>
>
> ANL would obviously be fine, but I was assuming that AC43 wouldn't be reco
mmending ANL fuses. Even with ANL, it's still weird that they would equate a
100A breaker to a 70A fuse.
>
>> On 12/7/2015 8:02 PM, Justin Jones wrote:
ring.com>
>>
>> The ANL fuse suggestion came from Bob's Z diagrams (note 10)
>>
>>
>>> On Dec 7, 2015, at 16:16, Charlie England <ceengland7@gmail.com> wrote:
>>>
il.com>
>>>
>>>> On 12/7/2015 6:02 PM, Justin Jones wrote:
spring.com>
>>>>
>>>> Hangar talk with a neighbor. He is designing a circuit using 4awg wire f
or his alternator. He asked me if he could use 2 - 50A circuit breakers wir
ed in Parallel for this purpose instead of a single 100A breaker. Chapter 11
in AC 43 says to use a 100A breaker or a 70A fuse for 4AWG wire. I suggeste
d the use of a 70A ANL fuse, but wasn=99t sure what the answer is to t
he CB question he had.
>>>>
>>>> Any insight?
>>>>
>>>> Justin
>>> No. (To using 2 breakers in parallel.)
>>>
>>> And that's a weird recommendation, too, unless the fuse mentioned is a s
pecial long-time-constant 'slow blow' type fuse. A breaker would take a lot l
onger to trip than a standard fuse of the same value; going 30A higher with t
he breaker *and* having slower response sounds really strange.
>>>
>>> Buying 2 50 A a/c breakers (or even one 100 A breaker) would just kill m
y (wallet's) soul. A fuse-able link would be lighter, take no panel space, a
*lot* cheaper, and if soldered in place, a *lot* more reliable than a break
er (no joints to corrode or contacts to fail). If it's properly sized, it sh
ouldn't need attention for the life of the a/c, unlike a CB.
>>>
>>> FWIW,
>>>
>>> Charlie
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
>
>
Message 11
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| Subject: | Re: Circuit breaker question |
Keep in mind that ANL are really current limiters (as opposed to fuses) whi
ch have a different (slower acting) current curve=C2- than a regular fuse
and/or breaker (faster acting).=C2- They can hold a little over their ra
ted value for a fairly long time (like minutes).=C2- Google "ANL current
curve" for details ...
-Jeff
On Monday, December 7, 2015 8:01 PM, Justin Jones <jmjones2000@mindspri
ng.com> wrote:
I thought it was strange too. It's table 11-3 on page 11-15 in chapter 11
of AC 43.13.1B
> On Dec 7, 2015, at 18:19, Charlie England <ceengland7@gmail.com> wrote:
>
l.com>
>
> ANL would obviously be fine, but I was assuming that AC43 wouldn't be rec
ommending ANL fuses. Even with ANL, it's still weird that they would equate
a 100A breaker to a 70A fuse.
>
>> On 12/7/2015 8:02 PM, Justin Jones wrote:
pring.com>
>>
>> The ANL fuse suggestion came from Bob's Z diagrams (note 10)
>>
>>=C2-
>>> On Dec 7, 2015, at 16:16, Charlie England <ceengland7@gmail.com> wrote:
>>>
ail.com>
>>>
>>>> On 12/7/2015 6:02 PM, Justin Jones wrote:
dspring.com>
>>>>
>>>> Hangar talk with a neighbor. He is designing a circuit using 4awg wire
for his alternator.=C2- He asked me if he could use 2 - 50A circuit brea
kers wired in Parallel for this purpose instead of a single 100A breaker. C
hapter 11 in AC 43 says to use a 100A breaker or a 70A fuse for 4AWG wire.
I suggested the use of a 70A ANL fuse, but wasn=99t sure what the ans
wer is to the CB question he had.
>>>>
>>>> Any insight?
>>>>
>>>> Justin
>>> No. (To using 2 breakers in parallel.)
>>>
>>> And that's a weird recommendation, too, unless the fuse mentioned is a
special long-time-constant 'slow blow' type fuse. A breaker would take a lo
t longer to trip than a standard fuse of the same value; going 30A higher w
ith the breaker *and* having slower response sounds really strange.
>>>
>>> Buying 2=C2- 50 A a/c breakers (or even one 100 A breaker) would just
kill my (wallet's) soul. A fuse-able link would be lighter, take no panel
space, a *lot* cheaper, and if soldered in place, a *lot* more reliable tha
n a breaker (no joints to corrode or contacts to fail). If it's properly si
zed, it shouldn't need attention for the life of the a/c, unlike a CB.
>>>
>>> FWIW,
>>>
>>> Charlie
>
>
>
>
>
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