Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Failed Contactor?

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

emrath(at)comcast.net
Guest

Posted: Sat Nov 29, 2008 8:06 am Post subject: Failed Contactor?

I was demonstrating my newly wired panel for family this weekend and the

contractor mysteriously dropped off line.  I had my battery charger

connected to the battery and system voltage was 13.3v DC.   When the master

is OFF, I'm seeing .5v between the two small contactor terminal with the

diode removed  and zero volts when the master is ON, yet contactor will not

activate.  All other external wiring checks out and the contractor is wired

per the B&C web site. System has been working fine up until now, any one

have ideas as to what has happened?  Did the Contactor suddenly go bad?



Marty  RV6A

Brentwood TN getting ready to paint!

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

nuckolls.bob(at)cox.net
Guest

Posted: Sat Nov 29, 2008 9:20 am Post subject: Failed Contactor?

At 10:02 AM 11/29/2008, you wrote:

 	  Quote: 	
		  



I was demonstrating my newly wired panel for family this weekend and the

contractor mysteriously dropped off line.  I had my battery charger

connected to the battery and system voltage was 13.3v DC.   When the master

is OFF, I'm seeing .5v between the two small contactor terminal with the

diode removed  and zero volts when the master is ON, yet contactor will not

activate.  All other external wiring checks out and the contractor is wired

per the B&C web site. System has been working fine up until now, any one

have ideas as to what has happened?  Did the Contactor suddenly go bad?


	


   The contactor will not operate until voltage between the two

   small terminals exceeds 8 volts or so. The voltages you

   cited for the two positions of the master switch were at or

   near zero. This means that the jumper between the fat battery

   terminal and the small coil terminal is open . . . or the

   wiring between the other small terminal through the master

   to ground has gone open.



        Bob . . .



        ----------------------------------------)

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

        ----------------------------------------

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

hooverra(at)verizon.net
Guest

Posted: Sun Nov 30, 2008 6:36 am Post subject: Failed Contactor?

Marty,

	Just to amplify what Bob has said.

A simple troubleshooting technique is as follows.



(Ground to operate circuit as in Master Contactor)

1. (Switch off) Measure from Ground to either small terminal should be

Battery voltage.

2. If 0 on both terminals battery supply is missing. If 0 on only one

terminal then the coil is open.

3. (Switch on) If both terminals are battery voltage the ground circuit

through the switch is open.

4. If one is battery and one is 0 then the contactor should operate. (If not

the coil is suspect).

5. If the coil is suspect measure it's DC resistance with an ohmmeter (I

imagine less than 100 ohms is good, It will probably be OK or open to very

high resistance, If shorted expect smoke)

6. As an aside a 12V test lamp between the ground side of the contactor and

battery ground should glow if the supply voltage is present, the coil is OK

and the switch is off. With the switch on it will go off if the ground

circuit is OK. 



Reading the voltage across the contactor coil verified that there is no

voltage drop and thus no operation but it doesn't tell you what part of the

circuit is open. Measuring to the battery ground tells you exactly what is

missing. 

	Usually parts are reliable (although not 100%), and problems are

found in installation workmanship. Suspect bad crimps and the like. (I have

been doing electronic wiring for 45 years and I still screw-up a crimp now

and again (crimp insulation only, cut the wire, not crimped tight etc.)).

Check everything!

	Happy hunting.



Ralph & Laura Hoover

RV7A N527LR

21 hours and having a ball

 



--

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum