Help...Power panel in galley buzzing sound?

Lifes Good

Hi,

Look for input on what would be causing a humming sound from behind the power panel in the galley.  It only buzzes while 110 is on at the dock.  If every thing is off on the panel it still buzzes.  Any ideas of what this is or the part that might need to be replaced?  2006 320FV. 

 

Thanks, LG

Boatin Bill

I am pretty sure the buzzing you are hearing is from what I think is a 110 volt to 12 volt transformer for your panel board. The buzz means it's working . It is located before the breaker so will be on as soon as you plug into power on turn on the generator.  Most of your 12 volt appliances and accessories work off this instead of thru your batteries.

TikiHut2

BB sounds like he has a good lead but if I heard a buzzing at the panel I'd pull the panel screws and look inside to confirm the sound. As a former electrician I've heard breakers buzz before failure but not hum like a transformer. There's no room for error if it's electrical in my book.

 I'd also guess that I'd want a bundle of tie wraps handy to clean up the possible rats nest of wires you'll find from typical hasty production boat assy. I'd run over every screw back there and ck each connector too. I'm of the train of thought that anything I dig into on the boat brings a better understanding of how all the systems work in harmony, and to understand what's up when the harmony ends.

Good luck. Mike 

Lifes Good

Guys thank you very much.  The sound is new as of yesterday.  So I am leaning towards something failing.  I will pull it apart and report back.  (Power off of course!).

PS I have tie-straps

LG

Lifes Good

Well I open up the power supply. All the wiring was very nicely bundled and tie strapped.  No rat nest.  There is a stainless box behind the power panel.  I opened that up and there are two of these units (picture).  The one in the picture is the one humming.  It appears to have shore power hooked to it  on the right and left sides.  (right and left are actually bottom and top). 

What is this and where can I find one?  I have a VM into Rinker so hope to hear from them too.

LG

Babyboomer

???????????????????????? Let us know what it is when you find out.

TikiHut2

Glad to hear about the build quality so save those wraps for a rainy day. Especially important is the stainless box that isolates the high voltage parts from your 12v system housing the contactor/relay . It sounds like the coil is getting tired or a contact is burned. The part is a contactor that most typical A/C or small appliance parts dealers should have on the shelf or be able to easily order at  far less than "marine" cost and there won't be any difference. It's an easy part to swap out just carefully label each wire as you remove them and carry the part to the A/C, small app store. (it goes w/o saying to use a tester and make sure that ALL power is OFF first)

A point of concern is the discoloration on the lower left and upper rt connectors indicating an over heated terminal either due to overloading, a loose screw or a poorly crimped connector.  You have a good ear to hear this issue before it escalated into a bigger deal or failed at an inconvenient time. 

Now it's time for me to pull our panel and see what there is to see. 

That's my .02c and thanks for posting, be safe and have a great season, Mike

Here's a real basic youtube clip on similar contactors often found in an A/C compressor etc:

http://www.youtube.com/watch?feature=player_detailpage&v=Id-XRKHWVhk

Lifes Good

Thanks Mike for the video!

I found these on line last night.  Glad to hear I can go to an appliance store to get one.  I did not see the model number on mine so maybe it's on the back.  I will pull it out and find a match.  Pricing looks reasonable thus far $25-$50.I noticed the discoloration on the crips too. Best to just replace and tighten appropriately.

LG - Mark

raybo3

Hey LG

Do you have 2 shore power hook up's on your boat? My guess its a contactor, one for each hook up. The fact that the sta-con's (crimp connectors) are dark is a build up of heat. Either a loose connecton or over current cause by the relay failing. Good luck and keep us posted

richtaylor1971

I know this is an old thread, but did anyone find out the part number or equivalent part# for the contactor, or # and name from a supier as mine is doing the same and wanted to order one in before taking all aprt , so I only do it , once.

richtaylor1971

guess not?

Grahamu

@richtaylor1971 do you have 2 shorepower plugs on the boat?

Handymans342

That looks like a standard 2 pole 30 Amp contactor with a 120 volt coil. Easy to find. When the contacts get worn and dirty they will cause the vibration. 

rasbury

It was cool to see the post from tikihut...

Grahamu

We had a 2006 342fv recently that had this problem. Turns out it was the relay that isolates the shorepower power inlets, forward and on the transom, from each other. We couldn't find comparable replacement so we put in a 3 way switch, on-off-on to select the shorepower inlet. This is the first boat where they used a relay that I have seen. The vast majority use a simple switch as above

MarkB

That buzzing sound is your warp core ... you need Scotty to help you.

LaRea

@Grahamu I don't think I've ever seen one with a relay.  Did it look like a factory install?

Grahamu

@LaRea. Yes it is a factory install there are 2 of them one for shorepower and one for the air conditioning inlet. They isolate the port side inlets and the transom inlets. My 342 has the same relays. Because a replacement relay was different to the original it was decided to remove the relay and put in a switch because we have to warranty it for at least 90 days. The boat mentioned above, it was the air conditioning inlet. I made an earlier post about the port side shore power inlet and how was it isolated as I couldn't figure it out at the time.

Handymans342

@Grahamu for what its worth, I have 2 contactors in a box in my RV that is involved with the generator transfer switch. 

Grahamu

@Handymans342, I have seen relays tied to a transfer switch, mainly on larger boats, but on my panel there is no switch to select which shore power inlet to connect to,

Handymans342

Why don't you just replace it with what I suggested???

Grahamu

My boat is fine, the boat that had the problem was in late summer and wanted a quick turn around and the Genny circuit was working okay, just the shore power circuits had the chattering relay.

richtaylor1971

@grahamu - sorry , only just saw this. yes I have 2 but like to have all working and not just one. As im in the UK, Ill search some US sites and see if I can locate what you said = 2 pole 30 Amp contactor with a 120 volt coil

Liberty44140

My 06 342 had the relay (auto switch) and it was factory. Had to be as there was no manual switch. Auto sensed which set of shore power inlets had power and used that switch only.