intellitec display out on shore power

[Mongobird]

For the first time in nearly a year since getting the 2004 Itasca Meridian, I have noted a possible inconsistency on the load center display.

It does not show Amps on 50A shore power.

It does show Amps on 20A short power.

It does show Amps on genset power.

Is this normal behavior? Is there a way to get the load display on 50A shore power?

Thanks, particularly to the similar Itasca and Winnebago owners who have more experience with this load display.

[imnprsd]

Your Amp Meter is not suppose to display Amps on shore power.

Why?

Answer: L1+L2 current will confuse you on shore power.

Why does my amp meter work on Generator and 30A and 20A power?

Answer: Because on these modes your current is "in phase."

MORE DETAILS:

Shore power (L1 & L2) is 180-degress out of phase. So on shore power your single neutral return line will subtract L1-L2, which is why I say you will be confused. So the masterminds decided you don't need to know what you don't need to know. Like the powers that be.

But on generator power (and 30A/20A) which is single phase, L1 gets added to L2 and so your amp meter will work.

==> If you look inside your main power panel you will see a terodial coil surrounding your Neutral Return Wire. So on Generator power, when L1 & L2 are in phase, then your current is ADDITIVE. I.e. you amp meter, when turned-on, is now summing L1+L2... and that makes sense... so they display the result.

Same goes for 30A and 20A since L1 is "dog boned" to L2, which means both your RV C1 and C2 are on L1.

[Mongobird]

@imnprsd, thanks for the dissertation! Complete with the charts with circles and arrows.

My expectation was different, and not that they would cheap out by using a single CT on the N. So I have two CT and a display now, which after I install it will let me monitor L1 and L2. But it won't be there on the console like the factory display.

(Another project is in the queue, which is to allow me to select running the refrigerator with the inverter. The priority will raise on that project once we identify a longer trip to take. And that will be a good time to install the monitor display and the two current transformers.)

I suppose most people don't care. But I would like to know. Also, I have a external diesel genset that I would like to use from time to time, and it would be nice to know that I am reasonably balancing loads between L1 and L2.

I saw your response earlier but did not have time to respond right away. Thanks again, and I hope your travels are going well.

[imnprsd]

Mongobird: Thanks for the PM message expressing your thanks. [Mod Edit]

===

I'm curious, what sort of refrigerator project are you talking about?

Do you have a residential refrigerator?

Next...

Did your 2004 come with the ability for your alternator to charge your house batteries while you drive? My 2004 Itasca "Horizon" 40AD did not... and my coach also came with a Cummins ISC. ...Since your coach came with a CAT, I think your wiring included some differences.

* One difference is in in the alternator charging/solenoid wiring as discussed above.

* The other difference is that my RV uses a VDC (with transducers) to convert air pressure in the primary and secondary tank to a readable format the electric PSI gauge on the dash uses. So, my question is: Do you know if your 2004-CAT uses a VDC located by the side radiator in back; or do you have an MMDC, which is located under your dash?

* Do you have a side radiator with your CAT?

[Mongobird]

Originally Posted by imnprsd

Mongobird: Thanks for the PM message expressing your thanks. [Mod Edit]

===

I'm curious, what sort of refrigerator project are you talking about?

Do you have a residential refrigerator?

Next...

Did your 2004 come with the ability for your alternator to charge your house batteries while you drive? My 2004 Itasca "Horizon" 40AD did not... and my coach also came with a Cummins ISC. ...Since your coach came with a CAT, I think your wiring included some differences.

* One difference is in in the alternator charging/solenoid wiring as discussed above.

* The other difference is that my RV uses a VDC (with transducers) to convert air pressure in the primary and secondary tank to a readable format the electric PSI gauge on the dash uses. So, my question is: Do you know if your 2004-CAT uses a VDC located by the side radiator in back; or do you have an MMDC, which is located under your dash?

* Do you have a side radiator with your CAT?

+ Absorption refrigerator. Runs off propane and 120V. I decided I do not want to run it off propane on the road. It can run off the inverter, but is not wired that way. So I will put a SPDT switch in, to allow me to run it off normal 120V as built, or off the inverter 120V. The inverter would be turned on when on the road, and the coach electrical powered by the alternator through the charge contactor up front. That is the same contactor which is used to supply "boost" for starting the rig.

+House battery charge. Provided by the same contactor (relay) which is used to bridge both batteries for "boost" starting, supplementally using the house batteries. When the propulsion engine runs, that contactor bridges both electrical systems, and allows both batteries to charge. (I don't like using this technique to charge coach batteries, but that is another thread for another time.)

+MMDC is used, and there are two "analog style" air pressure gauges show center on the console/dash. That data is available on the bus, and is also displayed on the problematic MMDC display. I say problematic, because the display LEDs were burned out and it was hard to read. A new one ($300) has working LEDs but the dash lights need to be on to really view things.

+No side radiator. A side condenser for chassis AC, and on the other side the Coleman heat pump. The radiator and the CAC are rear mounted on the engine. I have not owned this long enough to say how problematic that is.

[06ellipse]

Good evening! This post interested me. I recently was at a campground, hooked to 50A pedestal, and noticed the control board in the coach only showed 30A lit up.



When the genset is running, that light is lit.


If I understand your reply to mongobird correctly, because of how the 50A current is supplied, the control board will not show 50A indicator light lit up.


I guess I do not understand why there is a 50A indicator light if that is the case. When we left the campground I checked the 50A plug-in on the pedestal and has 120V on L1 and L2, so it was actually 50A coming in


When I say control board, I am talking about the panel with the tank levels indicators, power management panel, genset on/off, water pump on/off, etc.


Russ


2006 Itasca Ellipse 40FD
350 HP CAT C7

[cbeierl]

Originally Posted by 06ellipse

Good evening! This post interested me. I recently was at a campground, hooked to 50A pedestal, and noticed the control board in the coach only showed 30A lit up.

When the genset is running, that light is lit.

If I understand your reply to mongobird correctly, because of how the 50A current is supplied, the control board will not show 50A indicator light lit up.

I guess I do not understand why there is a 50A indicator light if that is the case. When we left the campground I checked the 50A plug-in on the pedestal and has 120V on L1 and L2, so it was actually 50A coming in

When I say control board, I am talking about the panel with the tank levels indicators, power management panel, genset on/off, water pump on/off, etc.

Russ

2006 Itasca Ellipse 40FD
350 HP CAT C7

Actually, that's not correct. When plugged into 50A shorepower the 50A light on the EMS should be illuminated. What you won't see on 50A is the amp load.

If you are plugged into a 50A source and your EMS panel shows 30A the most likely cause is one of your 120V circuit breakers turned off. The EMS uses one L2 circuit to help it detect 50A service (typically the right-most breaker in your panel, but not always)--if that breaker is turned off the EMS won't be able to detect 50A service and will show 30A instead and will also drop loads to stay within 30A if possible.

[imnprsd]

We aim to please, but unfortunately some people just can't be.

cbeirel makes a good point: Check your circuit breakers to see if one is tripped?

Note: You can also take off your metal circuit breaker cover panel to see how your EMS Intelletec #620 board is wired; and once inside, if you visually see a burned row of resistors let us know and we will send you notes on how to make a board repair. (See picture below.)

Also, each leg to the shore power pole is actually 100A, but because their are two 50A circuit breakers protecting the line (up to this point); then you really have 50A on L1 and 50A on L2.

Then your circuit breakers protect your "Circuit" loads (after that point); but we often use L1=C1 and L2=C2 interchangeably.

Once you piece power grid together it will probably look a lot like mine and the diagram below may be a good reference.

Notice: Your Inverter Panel (aka Sub-panel) is always L1 power and the OUTPUT from the 30A circuit breaker in the main panel goes to your Inverter ATS/relay to sense if there is power on the line (to automatically shut down the inverter) and then the C1 line goes to the Inverter Power panel.

Further, the coach ATS (Probably a Parallax 5070, which is the best ATS, even though you can't buy it anymore) will give priority power to the generator over shore power. So there are lots of things going on all at once, but in the end this method and madness is the best/cheapest way to handle all your power options.

Monogbird: Why are you spending any money to keep your old NeverCold running? Why don't you just put in a $800 residential refrigerator and become a real happy camper?

Note: I understand to limitations and costs of the labor if you can't handle this upgrade yourself; so if this is a concern, you can PM me your phone number and I will tell you how I got it done for cheap!

IMO, a residential refrigerator upgrade is the first best upgrade you can do. Then it's a tossup on adding 400W of solar and/or my latest upgrade which is to add a 8,000BTU portable AC... and then hiding it inside a living room cabinet so you hardly know it's there!

For more information on these upgrades you can do a search using "imnprsd" followed by your subject and see you you find.

Good luck!

[06ellipse]

Good morning Chris and imnprsd -


I appreciate your replies and insight.
I guess I caused this issue myself by leaving the circuit breakers for the washer/dryer off.
I do not have anything running on that circuit that I am aware of, so I left them off as "unused".
The next time we are out (about 2 weeks from now) I will have them on and will more than likely see 50A lit up.


Again, I appreciate the replies and all the information that can be picked up on these forums.


Russ


2006 Itasca Ellipse 40FD
350 HP CAT C7

[cbeierl]

Originally Posted by imnprsd

...
Also, each leg to the shore power pole is actually 100A, but because their are two 50A circuit breakers protecting the line (up to this point); then you really have 50A on L1 and 50A on L2....

Just a little correction since this is a bit garbled. Both legs together at the shore power pole support 50A at 240V. In the typical RV (excluding some high end ones which actually make use of 240V power) the two legs are treated as separate 50A 120V supplies, making a total of 100A of 120V power available to the RV.