ems

[gfryeday]

I have a 2004 Winnabago Brave the rear a/c works, but the Display on the EMS monitor show zero current. Is this the way it works or is this a problem, what could cause this? it is a 30 amp and i am running on generator.

[kmb1966]

Yours is like mine. The EMS manages the 30 amp shore cord service, but on the Generator one of the a/c units is wired to the 20 amp leg of the generator. Therefore nothing registers on the EMS in GEN mode on that a/c. When the 2nd A/C is turned on, it is on the 30 amp side and WILL register on the EMS.
It is working correctly. This threw me a confusion curve the first time I ran my A/C's on the Generator.

[pulsar]

dougrainer wrote:


YOUR system is a PCI brand system and will show amp draw on EACH leg with a total. But. the OP has a 30 amp RV and is 13 years old and PCI was not in business back then and the OP should have the Intellitec EMS system(Winne used that back then as well as 90% of OEM's). The Intellitec does NOT show amp use if on 30 amp service(30 amp system) or 50 amp if it is a 50 amp RV and is on 50 amps. You do have multiple sensors(2). The amp draw is taken from the current running thru the EACH 120 hot leg. There is a "donut" that the RED and Black lead runs thru and the PCI senses the current thru those 2 donuts. Intellitec systems read the current thru just the single NEUTRAL lead thru the same type donut. The advantage of the PCI system over the Intellitec is simple. Intellitec EMS system IF it fails or malfunctions, NONE of the appliances connected thru the EMS system will have 120 to them. PCI designed their system, if it fails, then the relays stay CLOSED and you have 120 power to all appliances on the EMS system. Doug

You certainly know more about ems than I do.

I'm only trying to counter the blanket statement, "If you have a 50 Amp MH, plugged into 50 Amp service the EMS will not show anything," which is not always true. Although in another thread, you imply that you agree with the blanket statement, now, it seems, you are agreeing with me.


Tom

[Crazy_Ray]

Wayne READ OP he has 2004 BRAVE

[Mickey53USA]

My experience with a 1999 Winnebago - 30 Amp. The rear (bedroom) A/C is not wired through the EMS or load shedder, therefore it does not show any amperage being used on the EMS panel. I would run both A/C units (both roof top) while on generator or plugged into a 30AMP RV outlet. If there is an overload, the EMS will shut things down that go through it, like the front A/C.

Just my experience.

[dougrainer]

pulsar wrote:

GPWayne wrote:
...

If you have a 50 Amp MH, plugged into 50 Amp service the EMS will not show anything. Not needed.
....

This statement is not always true.

These pictures were taken a 3 days ago, when the OP made his original post about this issue.





Both AC were running, when the pictures were taken.


Per wa8xym's post, perhaps my ems has multiple sensors.

Tom

YOUR system is a PCI brand system and will show amp draw on EACH leg with a total. But. the OP has a 30 amp RV and is 13 years old and PCI was not in business back then and the OP should have the Intellitec EMS system(Winne used that back then as well as 90% of OEM's). The Intellitec does NOT show amp use if on 30 amp service(30 amp system) or 50 amp if it is a 50 amp RV and is on 50 amps. You do have multiple sensors(2). The amp draw is taken from the current running thru the EACH 120 hot leg. There is a "donut" that the RED and Black lead runs thru and the PCI senses the current thru those 2 donuts. Intellitec systems read the current thru just the single NEUTRAL lead thru the same type donut. The advantage of the PCI system over the Intellitec is simple. Intellitec EMS system IF it fails or malfunctions, NONE of the appliances connected thru the EMS system will have 120 to them. PCI designed their system, if it fails, then the relays stay CLOSED and you have 120 power to all appliances on the EMS system. Doug

[pulsar]

GPWayne wrote:
...

If you have a 50 Amp MH, plugged into 50 Amp service the EMS will not show anything. Not needed.
....

This statement is not always true.

These pictures were taken a 3 days ago, when the OP made his original post about this issue.





Both AC were running, when the pictures were taken.


Per wa8xym's post, perhaps my ems has multiple sensors.

Tom

[wa8yxm]

The EMS is only active when on a 20 or 30 amp site,, If you are on a 50 amp site it goes to sleep cause it's not needed and the display will show zero amps.

Why is this.

Well you have two HOTS and a neutral. on a 50 amp site current can flow from L-1 to L-2 and bypass the neutral completely (Assumes a perfectly balanced panel) I can if you wish explain why this is a good thing.

So to properly measure current you would need 3 current sensors or at least two, and a comnputer to add 'em up.

But on 30 both L-1 and L-2 are the same, they are connected together. so ALL current flows through the NEUTRAL wire... So you need only one sensor, on the neutral.

Thus they do it that way. Far simpler, far less expensive, and just shut it off when you are on 50 amnps cause the reading would be ... Confusing.

[dougrainer]

gfryeday wrote:
I have a 2004 Winnabago Brave the rear a/c works, but the Display on the EMS monitor show zero current. Is this the way it works or is this a problem, what could cause this? it is a 30 amp and i am running on generator.

30 amp RV. When you have an EMS on a 30 amp RV. You cannot run both AC units at the same time. You CAN run both on Genset. The Rear AC is wired direct to the Genset. So, your EMS will not show amp draw. Doug

[Tom_Barb]

GPWayne wrote:

(Turn off the A/C before switching power***switching under load can cost $$$)

We simply start the generator, and the auto-transfer switch does it automatically. we do not need to shut one down first, then start the other. with the automatic transfer switch the generator has priority. start it up it takes the load. even with both A/cons on full.

[GPWayne]

What year MH? Are you plugged into 50 Amp service? Does the EMS monitor show a zero or nothing at all?

If you have a 50 Amp MH, plugged into 50 Amp service the EMS will not show anything. Not needed.

Try a 50 to 30 Amp adapter and you should get a reading or use the generator.
(Turn off the A/C before switching power***switching under load can cost $$$)

Do you have a Manual? If I had known what year you have I would have added a link to Wennabago Ind. Manuals are free to download.