Dave, For what it is worth when my standard Europa
supplied & wired rectifier failed, (over the Channel!),
the only thing that happened was that the ammeter showed
discharge directly related to how many bits of kit I left
switched on. Regards, David Joyce, G-XSDJ
Nigel Graham <nigel_graham@m-tecque.co.uk> wrote:
><nigel_graham@m-tecque.co.uk>
>
> Dave,
>
> The unit is a combination of rectifier and regulator.
> The issues you experience will depend on which component
>in which part of the circuit fails.
> There are (as far as I can identify - though I'm sure
>better qualified contributors will correct me if I'm
>wrong) three modes of failure.
> If you are really lucky, it will fail open-circuit, in
>which case everything continues to work fine but your
>battery discharges. The ammeter will show a discharge.
> If you're not so lucky, the regulator fails and sends
>unregulated DC to your battery. This will eventually boil
>dry, get very hot and may distort and if no over-voltage
>protection is fitted, take out your avionics.
> If you're really unlucky and the rectifier section
>fails, this can squirt unrectified AC into the main bus
>and kill just about everything except your ignition.
> Which CB breaks depends entirely on how your aircraft
>was wired up and it is these failure modes that have
>caused such spirited debate when discussing "the right
>way" to wire up a panel.
>
> Nigel
>
> On 07/04/2014 18:13, david park wrote:
>><dpark748@me.com>
>>
>> Nigel,
>> Would i be correct, in the event of regulator failure, i
>>am going to see?
>> 1.over/under voltage on volt meter ?
>> 2.main cb break?
>> 3.Ameter indication - discharge?
>>
>> Action - switch off alternator? And any unnecessary
>>drain on battery.
>> Dave Park
>>
>>
>> Sent from my iPhone
>>
>>
>>> On 7 Apr 2014, at 15:24, Nigel Graham
>>><nigel_graham@m-tecque.co.uk> wrote:
>>>
>>><nigel_graham@m-tecque.co.uk>
>>>
>>> This is an interesting discussion.
>>> If the aircraft wiring has been well designed and
>>>installed and if the correctly rated breaker (or fuse)
>>>has been installed to protect the desired equipment,
>>> then it is surely reasonable to suppose that the only
>>>time the breaker would pop, or the fuse blow, is if
>>>something has failed. No amount of in-flight fiddling is
>>>going to repair a shorted or broken wire, nor replace a
>>>failed capacitor, resistor or semiconductor (dare I
>>>mention Rotax/Ducati Regulator? ..... best not perhaps).
>>> Re-setting a popped breaker without identifying why it
>>>popped is surely asking for trouble. Do you wait for the
>>>first signs of smoke before finally getting the message?
>>>
>>> The only thing a pilot can do is recognise that a
>>>particular service has gone down and, depending on flight
>>>criticality, divert or continue.
>>> The only time to investigate the problem will be when
>>>you are safely down as the cause will almost invariably
>>>be in an inaccessible place.
>>>
>>> Popped breakers are easy to spot, but fuses are not
>>>immediately obvious - unless you have chosen the ones
>>>that Rowland has used which incorporate a "failure" LED.
>>> This does of course require them to be mounted where you
>>>can see them .......which brings us back to the OP.
>>>
>>> Nigel
>>>
>>>
>>>> On 07/04/2014 13:42, David Joyce wrote:
>>>><davidjoyce@doctors.org.uk>
>>>>
>>>> Rowland, I don't dispute the electrical safety. It is
>>>>just the distraction of having to dig around to make a
>>>>diagnosis and alter any circuitry rather than having it
>>>>plain obvious, right under your nose. I am strongly of
>>>>the opinion that anything that increases the
>>>>workload/distraction factor in an emergency is a
>>>>thoroughly bad thing and leads to a lot of stall/spin
>>>>deaths.
>>>> Regards, David
>>>>
>>>>
>>>> Rowland Carson <rowlandcarson@gmail.com> wrote:
>>>>><rowlandcarson@gmail.com>
>>>>>
>>>>>> On 7 Apr 2014, at 11:03, Brian Davies wrote:
>>>>>>
>>>>>> You make a very good point. The only electrical
>>>>>>incident I have experienced on my aircraft was a
>>>>>>generator overvolt trip just after coasting out over the
>>>>>>Channel. After a careful check and a reset of the
>>>>>>circuit breaker I was able to proceed without any drama.
>>>>>>The alternative, with a fuse not readily accessible,
>>>>>>would have been a turn back to the airfield/refiling
>>>>>>flight plan, revised GAR arrival time etc. etc.
>>>>>>
>>>>>> The safety aspects are even more important..
>>>>>
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: owner-europa-list-server@matronics.com
>>>>>>[mailto:owner-europa-list-server@matronics.com] On Behalf
>>>>>>Of David Joyce
>>>>>> Sent: 07 April 2014 10:16
>>>>>> To: europa-list@matronics.com
>>>>>> Subject: Re: Europa-List: Parcel Shelf tray door access
>>>>>>for fuses, CBS
>>>>>>
>>>>>> Tony & Rowland, I have a slightly different
>>>>>>philosophical approach to this question. A fuse may well
>>>>>>go as part of some in air failure just possibly
>>>>>>accompanied by fire or smoke. Time spent working out what
>>>>>>is happening threatens your safety. As with an engine
>>>>>>failure serious distraction and stress can lead to speed
>>>>>>decay and a stall/spin accident. So I prefer my fusing
>>>>>>system to be out where it is immediately obvious what has
>>>>>>blown and for this reason I recommend switchable circuit
>>>>>>breakers, all labelled and readily visible. They have the
>>>>>>added benefit of readily allowing switching off of
>>>>>>circuits to deal with emergencies such as regulator
>>>>>>failure. Regards, David Joyce, G-XSDJ
>>>>> David, Brian - thanks for your comments. I've tried to
>>>>>do simple Failure Mode & Effects Analysis (FMEA) on both
>>>>>types of circuit protection remembering that I'll be
>>>>>trying to fly the aeroplane at the same time. My planned
>>>>>"mission profile" is such that a failure of any single
>>>>>electrical item should not compromise flight safety, and
>>>>>in this I agree with Bob Nucknolls, who has a lot more
>>>>>experience than me in aircraft electrics. (With 32 years'
>>>>>professional experience in electronic research I feel I
>>>>>also know a bit about the "electrics" aspect if not the
>>>>>"aircraft" aspect.) See the following postings:
>>>>>
>>>>> http://www.aeroelectric.com/articles/fuseorcb.html
>>>>>
>>>>> http://www.aeroelectric.com/articles/fusvsbkr.html
>>>>>
>>>>> http://www.aeroelectric.com/articles/fusvbkr2.html
>>>>>
>>>>> You'll see there are strong arguments (& feelings!) on
>>>>>both sides. I can only say in the light of my own
>>>>>knowledge that I took time over my choice and feel
>>>>>comfortable with it.
>>>>>
>>>>> in friendship
>>>>>
>>>>> Rowland
>>>>>
>>>>> | Rowland Carson ... that's Rowland with a 'w'
>>>>>...
>>>>> | <rowlandcarson@gmail.com>
>>>>>http://www.rowlandcarson.org.uk
>>>>> | Skype, Twitter: rowland_carson Facebook: Rowland
>>>>>Carson
>>>>> | pictures: http://picasaweb.google.com/rowlandcarson
>>>>>
>>>>>
>>>>>
>>>>> Un/Subscription,
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>>>>> Admin.
>>>
>>>
>>>
>>>
>>
>>
>>
>>
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