Shorepower and Reverse Polarity - Page 3 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Chat  
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree1Likes
Reply
 
LinkBack Thread Tools
  #21  
Old 12-03-2007
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 14 Times in 12 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Layer 1 is always important to check...
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Quick reply to this message Share with Facebook
  #22  
Old 01-23-2015
captain jack's Avatar
Senior Member
 
Join Date: May 2013
Location: frederick, md
Posts: 1,496
Thanks: 122
Thanked 50 Times in 45 Posts
Rep Power: 2
captain jack is on a distinguished road
Re: Shorepower and Reverse Polarity

Quote:
Originally Posted by phaiakian View Post
credit goes to Art Richard IP32 #34 "Lagniappe" (St. Petersburg, FL) for the following dialogue:

"LOW GLOW OF REVERSE POLARITY LIGHT:
A low-level reverse polarity light on an IP when there is heavy current draw (like a heater or air conditioner) is not unusual. The reason is as follows:

1. The reverse polarity light is connected between the AC neutral (white) and AC ground (green) wires inside the distribution panel. If there is a voltage between these two lines, the light lights in proportion to the voltage.

2. When using shore power, the neutral and ground wires are connected together somewhere on the shore at a power distribution box. Between that point and your boat load (heater) are many feet of wire. Normally the AC current flows through the hot (black) wire to the load (heater) and back through the neutral (white) wire to the aforementioned distribution box (of course the current also flows through the black and white wire back to the power generator, but that is not pertinent to this discussion).

3. When current flows through a wire, the small resistance of the wire causes a voltage drop which is proportional to the length of the wire and the resistance of the wire. You see this on your AC voltage meter when you turn on a high current load (heater). Depending on the load and the length of wire, this voltage drop is sometimes 10 or more volts.

4. The reverse polarity lamp is effectively measuring the voltage between the neutral and ground wires at the boat. Since the ground wire is not (normally) carrying any current, there is no voltage drop in this wire. The neutral wire however is carrying current and does have a voltage drop. This voltage drop in the neutral wire appears across the reverse polarity lamp, causing it to glow, the brightness depending on the actual voltage drop in the neutral wire. This glow is not an indication of reverse polarity, and will not normally cause a problem.
ok. i have this problem as of last night. i do have a heater plugged in. it has been plugged in for a few weeks and this is the first time this has happened. my battery is low and i tried to charge it. but, when i plugged the charger into the socket (i thought i'd try since the heater seems to be working fine) the needle on it's meter kept jumping back and forth like crazy and i imediately unplugged it. figuring it really was a reverse polarity issue, i called the marina to tell them they should check the wiring at the dock because my reverse polarity light was on.

it is very dim. not bright. if i turned off the 15 amp breaker (leaving the 30 amp main on) the light would go off. so, i am guessing that this is, indeed, my problem. however, the charger was acting strangely. that makes me wonder. any thoughts?

certainly not trying to burn my boat up.
__________________
The only rules that really matter are these: what a man can do and what a man can't do.---Captain Jack Sparrow


1971 Cal 27

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #23  
Old 01-24-2015
Junior Member
 
Join Date: May 2009
Posts: 10
Thanks: 1
Thanked 1 Time in 1 Post
Rep Power: 0
pjs1554 is on a distinguished road
Re: Shorepower and Reverse Polarity

Captain Jack,

Could you clarify where the 15 amp breaker is? On your boat panel? Is this the same circuit as the heater was/is connected to? The heater does it have a fan or just the wire that glows?

Leakege to ground is not good. The two circuits ( ground and neutral ) should be isolated from each other all the way back to the main electrical service. With the corrosive environment involved it is not hard to understand why there are problems. Proper maintenance of the electrical system ( maria and yours ) should eliminate this problem.
Reply With Quote Quick reply to this message Share with Facebook
  #24  
Old 01-24-2015
captain jack's Avatar
Senior Member
 
Join Date: May 2013
Location: frederick, md
Posts: 1,496
Thanks: 122
Thanked 50 Times in 45 Posts
Rep Power: 2
captain jack is on a distinguished road
Re: Shorepower and Reverse Polarity

Quote:
Originally Posted by pjs1554 View Post
Captain Jack,

Could you clarify where the 15 amp breaker is? On your boat panel? Is this the same circuit as the heater was/is connected to? The heater does it have a fan or just the wire that glows?

Leakege to ground is not good. The two circuits ( ground and neutral ) should be isolated from each other all the way back to the main electrical service. With the corrosive environment involved it is not hard to understand why there are problems. Proper maintenance of the electrical system ( maria and yours ) should eliminate this problem.
it's an all new shore power system. the panel is a blue sea model with two breakers: a 30 amp main and a 15 amp branch breaker. the shore power plug is right in back of my breaker box so the distance between it and the panel is less than a foot worth of wire. all the wire gauges were chosen in compliance
with what's recommended for the loads....erring on the big side where it was close.

i have been using it for heat battery charging, and power tool for a few months, now, with no issues.

the heater was plugged into the 15 amp circuit. i have two plugs on that line (a distance from each other chosen specifically to allow me to place the heater at different points).

when i got to the boat my battery was way down so i couldn't turn on the lights, as i usually would at night. i had to use the led lantern i used to use before i installed the lights and it wasn't as bright inside i think and that's how i noticed the reverse polarity light was lit. it was dim and i had to check to make sure it was actually on, at first.

when i flicked off the 15 amp breaker, the reverse polarity light went out. turned it back on and the reverse polarity light came back on.

i plugged my phone charger into the socket and it worked just fine. the heater was also working just fine.

i unplugged my phone charger but, not the heater, and plugged in the battery charger. instead of the needle tanking at maximum charge, which is what should have happened, it bounced up and down rapidly. so, i unplugged it. i wish, now, that i had tried it with the heat off. going to do that today.

the heater has no blower. it's an oil filled radiator type...and i had it on maximum. since it has no blower, the full wattage (which is the same draw as my previous ceramic heater) goes into heat. it won't heat instantly but it keeps the boat much warmer inside than the ceramic heater with a blower.

the green and white wires make no connections, except the reverse polarity light which blue sea wired up, on board my boat. if there is a connection made, it's at the dock. i know not to do that and there is no chance it happened do to shoddy work. i am quality minded bordering on the obsessive.

that's all the details i can think to tell. i know the marina hasn't done any work on the electricity. the one thing not the best about them is that they are slow to get stuff done .

i had thught that it might be something caused by the weather. we have had a bit of rain and freezing rain, lately.

now, i'm thinking it's nothing to worry about but, i want to be sure.
__________________
The only rules that really matter are these: what a man can do and what a man can't do.---Captain Jack Sparrow


1971 Cal 27

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by captain jack; 01-24-2015 at 10:50 AM.
Reply With Quote Quick reply to this message Share with Facebook
  #25  
Old 01-24-2015
zeehag's Avatar
snake charmer, cat herder
 
Join Date: Nov 2008
Location: refitting a formosa in exotic tropical locations....
Posts: 1,749
Thanks: 8
Thanked 26 Times in 26 Posts
Rep Power: 7
zeehag is on a distinguished road
Re: Shorepower and Reverse Polarity

always make sure you twist lock your shore power cord to make connection correct. not twist locking your cord will cause arcing and potential fire.
ALWAYS double check your twist lock abilities each time.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

formosa 41, cruising tropics


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #26  
Old 01-24-2015
Old enough to know better
 
Join Date: Dec 2006
Location: Beacon, NY
Posts: 2,664
Thanks: 18
Thanked 102 Times in 98 Posts
Rep Power: 9
miatapaul is on a distinguished road
Re: Shorepower and Reverse Polarity

You are saying you plug in the charger, is this a regular car charger? The problem with most of those that I have read about is that the circuits do not have an isolated earth. So the car charger connects the 12 volt earth and the 120 volt and I think can cause issues like you are describing. If you have a marine isolated charger, never mind. But using an automotive charger on a boat is a big no no, as it can cause lots of issues with stray currents.
Reply With Quote Quick reply to this message Share with Facebook
  #27  
Old 01-24-2015
captain jack's Avatar
Senior Member
 
Join Date: May 2013
Location: frederick, md
Posts: 1,496
Thanks: 122
Thanked 50 Times in 45 Posts
Rep Power: 2
captain jack is on a distinguished road
Re: Shorepower and Reverse Polarity

Quote:
Originally Posted by miatapaul View Post
You are saying you plug in the charger, is this a regular car charger? The problem with most of those that I have read about is that the circuits do not have an isolated earth. So the car charger connects the 12 volt earth and the 120 volt and I think can cause issues like you are describing. If you have a marine isolated charger, never mind. But using an automotive charger on a boat is a big no no, as it can cause lots of issues with stray currents.
it is a car charger i am using temporarily til i get a permanent charger installed onboard. i hook it up when it needs a charge. i never had an issue with it before. the reverse polarity light was on before i tried using the charger. so, i don't think the charger was the issue.

to update.

i left the heater on and the shore power cord hooked up because there seemed to be no problem with the heater function. after reading up, i had wished i had turned it off and unplugged the cord. however, when i got to the boat today, the light was no longer on. (it was only dim before. not bright.) they never had a chance to check the dock electrics. (altough, they finally got the bubblers in place.) so, they did nothing to make the issue go away. but, away it went.

today, i had the heater on and i used the charger to recharge my battery. at first, the needle on the gauge on the charger acted squirrely again. i turned on the lights, as they should come on with the charger. they did but they flickered to match the needle. i turned the lights back off and continued with the charger. after a little, it steadied up like normal and everything went fine.

battery charged and i checked the lights. all is well.

the reverse polarity light never came back on; dimly or otherwise.

so, am i to assume it was just the draw of the heater?
__________________
The only rules that really matter are these: what a man can do and what a man can't do.---Captain Jack Sparrow


1971 Cal 27

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #28  
Old 01-25-2015
OPossumTX's Avatar
Senior Member
 
Join Date: Jul 2011
Location: Alvin, Texas
Posts: 181
Thanks: 28
Thanked 5 Times in 5 Posts
Rep Power: 4
OPossumTX is on a distinguished road
Re: Shorepower and Reverse Polarity

I do not know about your charger but the car charger I use with my trolling motor battery will cycle on and off like that if the battery is really low. I opened my charger up to replace the cord after the thing fell off the work bench while it was plugged in ripping the cord out. Inside mine there is one of those automatically resetting thermal breakers in series with the red battery cable. If the battery pulls more than 6 Ampres or the charger leads get shorted, the breaker starts doing its click-tick routine until the short is cleared or the battery charges enough for the current to drop below 6 A or so. Real MODERN battery chargers have electronics to limit the current and control the charge voltage. My 30+ year old "6A BATTERY CHARGER" has a selenium rectifier stack, a very roogie looking transformer, a neon pilot light, the amp gauge and that click-tick breaker I told you about. There is nothing else inside the thing. If I leave it on a battery too long it will boil that suckka DRY!

I have learned to shut it off after a few hours at most. I should have pitched the junker years ago but the cracker box still works, so...

Have FUN!
O'
Reply With Quote Quick reply to this message Share with Facebook
The Following User Says Thank You to OPossumTX For This Useful Post:
captain jack (01-25-2015)
  #29  
Old 01-25-2015
captain jack's Avatar
Senior Member
 
Join Date: May 2013
Location: frederick, md
Posts: 1,496
Thanks: 122
Thanked 50 Times in 45 Posts
Rep Power: 2
captain jack is on a distinguished road
Re: Shorepower and Reverse Polarity

Quote:
Originally Posted by OPossumTX View Post
I do not know about your charger but the car charger I use with my trolling motor battery will cycle on and off like that if the battery is really low. I opened my charger up to replace the cord after the thing fell off the work bench while it was plugged in ripping the cord out. Inside mine there is one of those automatically resetting thermal breakers in series with the red battery cable. If the battery pulls more than 6 Ampres or the charger leads get shorted, the breaker starts doing its click-tick routine until the short is cleared or the battery charges enough for the current to drop below 6 A or so. Real MODERN battery chargers have electronics to limit the current and control the charge voltage. My 30+ year old "6A BATTERY CHARGER" has a selenium rectifier stack, a very roogie looking transformer, a neon pilot light, the amp gauge and that click-tick breaker I told you about. There is nothing else inside the thing. If I leave it on a battery too long it will boil that suckka DRY!

I have learned to shut it off after a few hours at most. I should have pitched the junker years ago but the cracker box still works, so...

Have FUN!
O'
mine isn't that old. it does self maintain. if it fills the battery, it shuts off. however, i was thinking that might be what's behind the way the charger was acting but, i wasn't sure. now, thanks to you, i am.

it still leaves me with that question about the dimly lit reverse polarity light, though.
__________________
The only rules that really matter are these: what a man can do and what a man can't do.---Captain Jack Sparrow


1971 Cal 27

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #30  
Old 01-25-2015
Member
 
Join Date: Feb 2007
Location: Virginia
Posts: 74
Thanks: 1
Thanked 2 Times in 2 Posts
Rep Power: 9
bhcva is on a distinguished road
Re: Shorepower and Reverse Polarity

My reverse polarity light always comes on dimly when the hot water heater or other source draws a high current. I had it checked and was told it was not a problem. It has done it since the boat was new (94) and has never been a problem. I am at the end of a dock about 14 boats away from shore...long run.
captain jack likes this.
__________________
"Solitude" Caliber 40
Ches Bay
Reply With Quote Quick reply to this message Share with Facebook
The Following User Says Thank You to bhcva For This Useful Post:
captain jack (01-25-2015)
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On



All times are GMT -4. The time now is 07:38 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.