NCMARTEC STUDENTS WINS 100 GRAND!!!!
******HEADLINE NEWS******
Marine Electrical II student Phil Lindsey won 100 Grand by solving the open challenge problem of wiring 6 bilge pumps to one panel with one single indicator light. Phil’s schematic includes 6 strategically placed diodes disallowing current from backfeeding the other pumps, while allowing the light to be wired in parallel. Congrats, Phil. What are you going to do with the 100 Grand???
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Welcome to Marine DC Electrical I at NCMARTEC! Marine electrical installation can be as rewarding as it can be frustrating. It Marine electrical installation requires some foresight, planning, and technical ability to successfully allow electricity and salt water to safely coexist. Many more considerations exist than crimping some wires to a bilge pump and wrapping the ends around a battery. What sort of wire is used? How is it insulated? How are the ends connected? How is the battery maintained? What sort of battery is required? How much will it cost?
These are questions to which we will find answers. Whether you wish to become a competent and knowledgeable marine technician, or you own a boat and want to know more about your electrical system, you are in the right place. If you have a battery in a jonboat, you have an electrical system.
Welcome. Check back for content updates weekly.
Sean Prendergast, Marine Systems Instructor
MDC1 Marine Electical 
Sean, I am bringing some wire to class tonight and I want you to look at it tell me if it can be used the marine environment.
Phil Lindsey
By: Phil Lindsey on August 22, 2007
at 6:46 pm
Phil,
Thanks for the first post to MDC I! Good question. We will examine what you bring in tonight and determine if it is acceptable for your specific application. Upcoming lessons will cover what is acceptable conductor and insulation for particular uses in the marine environment (interior wiring, engine room wiring, exterior applications, etc). But, bring it in and we’ll check it out.
Sean
By: ncmartec on August 22, 2007
at 8:09 pm
happy to be onboard.
By: patrick dallas on August 27, 2007
at 4:29 pm
Sean,
Yesterday you asked us, which has more resistance, an oven or a……. I can’t remember what was the other appliance. Can you please tell us again? Thanks.
Harry
By: Harry Alicea on August 28, 2007
at 4:22 pm
We know that electrical resistance always yields heat. We know Ohm’s Law: V=IR
So, which appliance has more resistance, an electric stove element, or a console-mounted GPS unit?
A or B, but more importantly, why?
Sean P.
By: ncmartec on August 28, 2007
at 6:06 pm
The GPS has alot more resistance than a electrive stove element.
Reason why. For example a gps system can run either on 12 or 24 VDC. The most amps it will draw if hooked properly is 240 -120 mA.
24 VDC/ .240 A = 100 Ohms
An electric stove that runs out 220 VAC minimum fuse u will install is a 30 Amp, even though a 50 amp is recommended. So lets say
220 VAC/ 30 AMP = 7.33 Ohms
The stove element porpuse is to create heat, so the more Volts and Amps u add with very lil resistance equals to alot of heat, which is cooking my dinner.
Harry
By: Harry Alicea on August 28, 2007
at 10:30 pm
Harry, good reasoning. But, if resistance = heat, doesn’t a lot of heat = a lot of resistance? How hot does a GPS get?
By: ncmartec on August 28, 2007
at 11:49 pm
I’m meant to say low resistance = high heat. The gps has alot of resistance so it doesn’t get hot.
By: Harry Alicea on August 29, 2007
at 2:32 am
Does anyone else concur with Mr. Alicea?
By: ncmartec on August 29, 2007
at 1:45 pm
Sean, The positive wire running to the primary solinoid post is a switched wire, right? Fred
By: Fred Walker on September 13, 2007
at 10:49 am
Fred, postive wire running to primary field of solenoid is switched, yes. My question for you: what makes it switched?
By: ncmartec on September 13, 2007
at 2:41 pm
Sean;
what kind of weasel deal is this, where’s my hundred grand
Phil
By: Phil Lindsey on October 18, 2007
at 9:34 am
Class,
As Phil so humbly pointed out, he successfully solved the 6 Bilge Pump, One Light, No Backfeed problem by installing a diode into the ground side of each pump.
Phil,
Your Hundred Grand will be waiting for you on your desk on Monday, October 29. Feel free to share it with anyone in the class. Get ready to work on Monday.
By: ncmartec on October 25, 2007
at 3:08 pm
Class,
Professional Boatbuilder magazine is being offered to NCMARTEC Marine Electrical students for free. That’s right – free. It is a great magazine, has definitive articles on different topics pertaining to the professional builder and repairman, and is free to you because you are a student. The link has been added to the Blogroll.
Sean P.
By: ncmartec on October 25, 2007
at 3:13 pm
Sean,
I am really impressed with your Blog. The design and template you chose works well for your content – I would make the banner a little narrower – otherwise you be bloggin man.
Patrick
By: Patrick Keough on October 26, 2007
at 8:04 am
Sean,
Have you located name or phone # for manufacturer of push button latches for cabinet doors?
Pat
By: patrick dallas on November 7, 2007
at 12:08 pm
Pat,
Yes, thanks for the reminder. The name of the company is Southco Marine, Inc. They supply a full line of latches, hinges, deck hardware, etc. They recently acquired Orcas Marine also a large supplier of hardware. Their website, http://www.southcomarine.com has a full product listing and full specs on each product.
I visited their booth at IBEX – great stuff.
Contact info:
Southco Marine Inc.
4340 Fortune Place Ste. A
West Melbourne, Fl 32904
panderberg@southcomarine.com
http://www.southcomarine.com
By: ncmartec on November 7, 2007
at 2:07 pm