Reverse Polarity Indicator Wiring

[britinusa]

Yes, I searched for this issue, mine is a bit unique.

Our boat (1987 Mk 1) had a new electrical panel or update around 2006 looking at the documentation that came with the boat (I'm at least the 3rd owner).

Over the years, the wiring behind the panel has turned into spaghetti junction, the wire terminals are awful, AC connections are Wirenuts, Circuit breakers have as many as 4 terminals connected on the switched side, there are more butt connections than I have ever seen on a boat. Wire colors and sizes are not either consistent or appropriate and labels - electrical tape that may have something written in crayola years ago.

As I prepare for a major update on the wiring behind the panel, I inspected the AC breakers and in particular, the Reverse Polarity Indicator. The attached photo shows the R.P. Test Switch and lamp, note the empty switch tab. The attached diagram shows what I believe is the correct wiring for the Reverse Polarity Indicator system. (the red wire is the one I believe is missing).

I know that I can purchase a Reverse Polarity Plug to test the shore power at any dock we plug into, but the existing system has the facility, it's just that it doesn't work (at least, I can't see how it works)

Any suggestions? Note. We do have a Galvanic Isolator installed between the Shore Power boat side plug and before a Zantrex Freedom 20 Inverter Charger.

TIA.

Paul

[Stu Jackson]

Paul, you seem to be showing two RP lamps and resistors, but only one is connected to the switch. 

ground >>> neutral shouldn't light
ground >>> hot should light

Do you have two lamps on your panel?

[britinusa]

Sorry, I should have labeled both indicators. (and spelt Neutral correctly  )

The second (top, unlabeled) LED just shows that Shore Power is available before making the AC Main Switch.

If the Neutral line is HOT then the Reverse Polarity Warning Lamp would illuminate.

If the RP  Warning lamp is not illuminated, then a quick press of the spring loaded Lamp Test Switch will illuminate the lamp (because it connects the lamp to the correctly HOT line and Earth.)

[Stu Jackson]

Thanks for the clarification.  So going back to your original question:  Could you not simply set up a test wire and temporarily connect it to see if the light works?  If it does, then do a permanent one.

[britinusa]

Currently (no pun intended) the light works. When I press the spring loaded Lamp Test Switch, it illuminates.

The issue is that I cannot test if the shore power terminals were incorrectly connected - reverse polarity.

Right now, if we plug in Shore Power, the AC Ready light illuminates, we then have been operating the Lamp Test switch, just to test the lamp. But we didn't realize that the wiring was not installed correctly, as a result, if the polarity was reversed, we would not be aware of it.

I'm not replacing the panel, which has the two lamps installed. I'm just rewiring it so that it's easier to maintain and I should sleep better at night (subject to the weather) 

[KWKloeber]

Hey Paul (you didn't research it enuf. LOL.

Here's OEM:

The center tab on the mom contact rocker sw is the common terminal.
That goes to the light, wired to the neutral pole of the main breaker.

The NC terminal goes to the ground buss.
Ipso, any RP voltage will touch off the RP light (neutral flowing to ground.)

The NO terminal goes to the hot pole of the main breaker.
Ipso, that tests the bulb (hot flowing to neutral.)

Mine has no test sw, so one doesn't know whether the bulb is good or burned out. That's how the mk-I manual shows it (no switch, bulb permanently wired between the neutral and ground.)
The mk-II manual shows the test switch. Check the manual on the wiki.

HOWEVER, depending where the GI sits I could see a conflict.

If the GI is before the RP light, I don't see how it would work, since the GI breaks the ground continuity. Maybe current thru the light (if there's a RP fault) would inch past the GI?

If the GI is after the RP then I'd think that the NC light circuit would negate the purpose of the GI.

Caveat: my degree is in CEE, not ECE. 
Maybe Jeremy or Rod Collins will chime in about the GI?

I don't see why there's resistors on either light?  There none on my RP (that I know of.). Caveat: see caveat #1.

Cheers
Ken

PS, nitpicking but I'd label your switch terms; NC, C, NO.

[britinusa]

Thanks Ken.
NC - NO Switch Common is to the lamp
The NO is to Hot
The NC is empty

The RP lamp is connected to the switch common and to to the Neutral pre-switched side of the circuit breaker.

The GI is connected to the earth just inside of the Boat Side Connector before the the AC Main Switch

The 110v is routed from the AC Main Switch -> the Inverter and from there to the Panel.

I left out the GI and the Inverter just to keep it simple.

I'll re-label the switch and include the GI and Inverter for clarity.

:)

Paul

[britinusa]

After reviewing the actual wiring -v- the sketch that came with the boat docs, I conclude that this is the actual wiring's diagram

[Stu Jackson]

After reviewing the actual wiring -v- the sketch that came with the boat docs, I conclude that this is the actual wiring's diagram

Paul, WADR, that diagram makes no sense.  Maybe that's why you're having problems.   

I wrote earlier:

ground >>> neutral shouldn't light
ground >>> hot should light

I only wrote that AFTER I consulted with Calder's bible.

And this:  https://www.bluesea.com/support/articles/AC_Circuits/90/Reverse_Polarity_Indicators

Your new diagram shows the RP connecting the hot and neutral, and then the neutral and itself!  And then only if the AC main breaker is closed.

It also shows the Freedom 20 AFTER the incoming shorepower, which also makes no sense.  I have a Freedom 15.  I wired it to the entire A.C. service on my boat - I installed it myself.  Because the Freedom units have Automatic Transfer Switches (ATS) in them, the shorepower should go to the Freedom unit FIRST, and then to the main AC breaker: shorepower >> Freedom (ATS) >> main A.C. breaker >>  A.C. loads (i.e., water heater and receptacles; I manage the water heater by assuring it is OFF when I engage the inverter which also serves my receptacles including my microwave which is hard wired into the galley receptacle). 

Unless you have wired the Freedom to a separate subpanel which ONLY feeds selected loads, like only your receptacles, if you have it wired to everything A.C. on your boat, your diagram is wrong regarding the Freedom unit.  I do understand that was not the intent of your whole diagram but thought it prudent to point this out to you (and any others who may be following this and wiring diagrams).

[britinusa]

I believe that the freedom was installed according to the Rabbit DIY kit sometime around 2006.

The wiring is a nightmare to figure out on the boat, so I'm going from their diagrams.

A second issue is that I know the some of the wiring is incorrect and the on the boat wiring does not match the installation instructions. eg. The boat has two external regulators, one is connected to the link 2000 system, but it's not connected to the Alternator, the 'standby' regulator is connected to the alternator.  The Solar output is not connected according to the wiring diagram in the diy kit.

So I'm anticipating that there will be other errors/alterations. It's because I couldn't make sense of it that I drew the diagrams from the hand drawn sketch in the docs that came with the boat and from the dozens of photos I have taken.

At the end of the day, when we start to pull all of the wiring from behind the panel, I'll have a better idea of what was there.  I have figured out the correct wiring for the panel, but that's pretty straight forward. I'll follow the link you provided Stu to see if I can adapt what we have to what we should have.

Paul

[britinusa]

When  I view the blueseas link, none of the images show:) I'll see if contacting them gets anywhere.   (I'm using blue sea terminal blocks and new LEDs - surely they'll respond as I'm such a big spender      )

[Stu Jackson]

When  I view the blueseas link, none of the images show:) I'll see if contacting them gets anywhere.   (I'm using blue sea terminal blocks and new LEDs - surely they'll respond as I'm such a big spender      )

Here it is: 

[britinusa]

Thanks Stu.

That's the basis of my circuit. They do have a really nice panel with their system installed for both shore and gen power circuits. I couldn't find the circuit they used for it however.

:)

Paul

[KWKloeber]

Paul

I attached what *should* have been your RP wiring (I didn't address anything about the freedom.) 

If you reference the two owners manuals (on the wiki) you'll see the attached is equivalent.     

The RP voltage would be above 1.2v, so if a RP fault occurs the GI will pass thru the current from the indicator lamp.

Note that the BlueSea RP diagram has no test function so the lamp could fail and a RP condition not be indicated.

[PS  If the dashed lines indicate the boatside shore power inlet, the Gi should be in the boat side.]

[britinusa]

Thanks Ken, I really appreciate the effort you put into that.
You are correct, the GI should be shown on the boat side of the diagram.

Using that, and talking (email) with blue sea, and re-reading Don Casey's Sailboat Electrics Simplified, I came up with this schematic.

It provides continuous indication of a reverse polarity test and shows when Shore Power / Gen Power is connected and switched on.

Blue sea confirmed that the LED's that I purchased have 33kΩ but I will test that they illuminate when connected.