420DB – Bridge A/C and Heat Installation

Thanks for the tip, Jeff. I'll look in to it.
 
Why not use something like a breaker lockout device? http://www.bradyid.com/bradyid/pdpv/51254.html Check out the demo video. You couldn't necessarily have to go through the whole drill using a lock per say, just screw the device and lock it onto the breaker.

Install all 3 AC breakers directly next to each other in the panel for easier viewing. Then engrave a small tag which says something to the effect what you posted above (only 2 AC breakers on at once, 1 breaker locked out).

Doug
 
Doug,

I'm sure you know that boat breakers are different and this lock won't fit. I looked at the video and to be honest with you I didn't like it. I think that toggle switch is much better instead of the lockout device for this application. Anyway, thanks for the suggestion.
 
They make different styles for different applications. Just the concept I was trying to get across.
 
Ok, got you.
 
Alex F said:
For those who's not very familiar with what it'll do, here's a quick explanation. I'll label the units for argument sake:
#1=salon
#2=FWD stateroom
#3=bridge

My goal is to allow for only any given TWO units to have power supplied to them. This way only TWO units can run at the same time. Let's say the switch has positions 1 & 2. In position 1 it'll supply power to units #1 and #2 (salon and FWD), this means that unit #3 (bridge A/C) will be dead with no power. When I want to run unit #3 I'll flip the switch to position 2 where it'll feed another set of units (#1 and #3) disconnecting the juice from unit #2 (FWD).

I think this is very simple and effective solution. Now I can sign and send my waver to SR......oh crap, I'm out of warranty.
Click to expand...

My only limit is to not run the fwd and bridge at the same time - much simpler. It is because they are wired on the same side of the AC power panel.
 
Hampton said:
My only limit is to not run the fwd and bridge at the same time - much simpler. It is because they are wired on the same side of the AC power panel.
Click to expand...

I'll have the same issue, John. It seams like the way SR designed our panels they filled all slots on the port side and left couple of blanks on the stbd side. However, I think that the global issue lacking the power exist regardless. I thought of moving some items like washer/dryer, but I'm not sure that it'll make a big difference.
 
Hampton said:
My only limit is to not run the fwd and bridge at the same time - much simpler. It is because they are wired on the same side of the AC power panel.
Click to expand...

Alex F said:
I'll have the same issue, John. It seams like the way SR designed our panels they filled all slots on the port side and left couple of blanks on the stbd side. However, I think that the global issue lacking the power exist regardless. I thought of moving some items like washer/dryer, but I'm not sure that it'll make a big difference.
Click to expand...

Alex,

If that is the case then why don't you use the breaker lock like it was stated by Douglee? I think it is similar to how my panel is hooked up between the Generator and Shore Power. One has to be switched off and the bar slid over it before the other one can be turned on. Very simple and also idiot proof!!!
 
You could either call Carling direct and see if they make a different style breaker - http://www.carlingtech.com/

Or they make other brands of breakers that should fit in the same space as your originals that have a different style switch.

Doug
 
Alex, I agree with your toggle switch between your bridge & forward A/C being the simplest and most sure proof approach.
Art
 
Just catching up with this.

What about using a relay so that when one unit is on, it locks the other out. You could pick which unit has priority.

With this approach, you could leave both ac units on.

For example: Let's say you wire it so forward air has priority (better chance that this zone will get satisfied). Once the forward AC condenser shuts off, the bridge unit can turn on. Forward fan can still run to circulate air.

If you want bridge to run full time, just turn off the forward air. You can do this from the thermostat also, no need to flip breakers.

Maybe use time delay relays to prevent short cycling.

Just a thought, I didn't work it all through yet.

edit - I see I already thought of this (post 69)
 
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Greg said:
...What about using a relay so that when one unit is on, it locks the other out. You could pick which unit has priority....
Click to expand...

Greg,

I assume you're referring to something different than PLC unitls. Do you have some links to the relays I could get an idea from?

In regards the thermostats programming, I just don't trust them to be boolletproof. There were way too many times when I switch from shore power to genny and/or back and the thermostat that was turned off (I turn every unit off at the thermostat before shutting down and switching power) would come on on it's own, without me manually clicking the "cool" button. I don't remember this happening in the heating mode, but in cooling mode it does happen. So, if the thermostat has a mind of it's own I can't take the chance and allow all 3 units to kick in at the same time. This is where the toggle switch seams to provide boolletproof solution. But, I'd love to hear more about the relays.
 
Ok I sat down and figured out your circuit diagram. You can do this a couple of ways I would image, but here's what I came up with....

You will have 3 breakers....

Breaker #1 - Existing Front bed AC
Breaker #2 - Existing Salon AC
Breaker #3 - New Bridge AC installed

You will have to do some rewiring to get this part correct.

You will wire in a 3 way switch after breaker #1 and breaker #3.

In the configuration, the salon AC is controlled just like today by switching the breaker on or off.

By wiring in a 3 way switch after the front bed AC breaker and the new bridge AC breaker, you will select either the front bed AC or the bridge AC with the switch. Therefore, the breakers still provide overload protection on each individual circuit, but the 3 way switch gives you the option to select either the front or the bridge AC in conjunction with the salon AC unit.

I made the assumtion that the salon unit could potentially always run. With this configuration, you would not be able to run both the bridge and the front AC unit together.

In the end, you can only run two out of three units at the same time providing you with the ability to manage your amperage draw.

Does that work for you?

Doug
 
If that's an accurate number, or even remotely close, you'll be able to maintain any temperature you want, especially if you have it on starting at the beginning of the day. Just remember, thermal mass is your friend or enemy...
 
Also, you should be able to approximate the square footage of the cooling space. L x W x H. Take that total, and divide that by 1250. That will tell you how many times per minute that entire bridge air is cycling through that unit, the more cycles, the cooler the air will be. Each cycle will have roughly the same delta drop.
 
One last thing...

I'm thinking that a three way switch is not the way to go. Personally, I would install the system and see how it goes with power managment, then make any small changes near the main breakers as you deem necessary.

My take is, you won't need them at all...
 
douglee25 said:
Ok I sat down and figured out your circuit diagram. You can do this a couple of ways I would image, but here's what I came up with....

You will have 3 breakers....

Breaker #1 - Existing Front bed AC
Breaker #2 - Existing Salon AC
Breaker #3 - New Bridge AC installed

You will have to do some rewiring to get this part correct.

You will wire in a 3 way switch after breaker #1 and breaker #3.

In the configuration, the salon AC is controlled just like today by switching the breaker on or off.

By wiring in a 3 way switch after the front bed AC breaker and the new bridge AC breaker, you will select either the front bed AC or the bridge AC with the switch. Therefore, the breakers still provide overload protection on each individual circuit, but the 3 way switch gives you the option to select either the front or the bridge AC in conjunction with the salon AC unit.

I made the assumtion that the salon unit could potentially always run. With this configuration, you would not be able to run both the bridge and the front AC unit together.

In the end, you can only run two out of three units at the same time providing you with the ability to manage your amperage draw.

Does that work for you?

Doug
Click to expand...

Thanks Doug.

You're right, a 3-way switch or a toggle switch will require some rewiring. I will have to find a good place to mount the switch.

beachcombersc said:
Also, you should be able to approximate the square footage of the cooling space. L x W x H. Take that total, and divide that by 1250. That will tell you how many times per minute that entire bridge air is cycling through that unit, the more cycles, the cooler the air will be. Each cycle will have roughly the same delta drop.
Click to expand...

My bridge is just under 900sq/ft. (14.5'x6.6'x9.5'). According to your formula 900/1250=.72, I hope that's good.

beachcombersc said:
One last thing...

I'm thinking that a three way switch is not the way to go. Personally, I would install the system and see how it goes with power managment, then make any small changes near the main breakers as you deem necessary.

My take is, you won't need them at all...
Click to expand...

Most likely this is going to be my approach:
1. Basic installation.
2. Validation and further assessment.
3. Enhancements and add-ons, including switches and additional vents (if any needed).
 
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