Is there a single unit device that provides battery charging, dc power to coach, pure sine wave inverter and transfer of power between batteries, genset and shore power? Need to minimize number of devices in the 22' Euro.

Hi Tom, I didn't take care for the number of devices to do the functions you want to do.

I am not aware of a inverter/charger that has a built in transfer switch to manage AC power. I have the Magnum 2800 that is a pure sine ave inverter and a 130 amp battery charger. In use a standard transfer relay used in most RVs to handle shore/generator power. The inverter sense the presence of AC power and will come on line if there is no AC available. I bypass the inverter and go straight from the transfer relay to both air conditioners.

When the inverter/charger lists a transfer switch or relay (You want this function), that is only referring to transferring the operation from AC to battery power (inverter). It does not switch between shore power and generator power.

Pure sine units have gotten fairly inexpensive. price goes up when a battery charger is added.

I would contact Don Rowe Associates they handle a complete line. Personally I would advise to stay away from Xantrex products, product support has been BAD!

Don Rowe

My opinion is the Magnum products are the best.
Are your Energenus units crapping out? mine is still going.

I am not sure what is in the coach; just found one grey box that is plugged into a standard duplex receptacle in a closet. Figured it must be a 1981 so also fugured to replace with new technology. Small coach so need to minimize the size and number of devices. Am adding another basement compartment to mount four Trojan Golf Cart batteries to extend and support new appliances and devices. It has two 12v deep cycles now that I plan to replace.

I don't know of any inverter/chargers with integrated auto transfer switches.
But they are small in size so should not cramp your space.
I would like to see an auto transfer with a manual over-ride in the event of relay solenoid failure.

quote:

Originally posted by L78steve:
But they are small in size so should not cramp your space.
I would like to see an auto transfer with a manual over-ride in the event of relay solenoid failure.

So would I... or at least relays with sockets to allow quick replacement. The relays in mine are all soldered into the PCB and would require major diassembly to get at to replace.

I decided to make some jumpers to bypass the transfer switch when (not if) the relays fail.

Strong caution! I would not use jumpers for any issue with the transfer relay unless you would have a FULL disconnect of the relay from both inputs from the shore power and generator and output to the coach AC system.

Relays can fail in either the open or closed position. Most systems have a priority connect system. On mine, when connected to shore power, the coach AC system is connected directly to the shore power plug and the generator is off line and isolated. I start the generator, when The transfer relay system is happy with the generator voltage, The transfer relay will first disconnect the shore power and then connect to the generator.

If the transfer relay were to hand up in either position, jumping around the transfer relay could apply AC from the shore power directly to the generator or the generator connecting to the live shore power.

This would have nasty results!

To clear up any confusion about "transfer relays":

The term "transfer relay" is normally used to identify a relay that would control the source of AC, either shore power or generator power to the coach AC system.

Some inverter/charger manufacturers list a transfer relay is included either internally or externally. A transfer relay used with the inverter will allow external AC (from the main transfer relay either shore or generator power) to bypass the inverter. If the inverter transfer relay senses that the external power in not present or no good, then the inverter switches on and will supply to the coach AC system. Shore power and generator sources are disconnected from the inverter to prevent back feed.

If input from shore power or generator AC is sensed by the inverter to be stable and good, then the inverter transfer relay will switch off the inverter and connect the external source of AC bypassing the inverter.

HTH

So, if this coach is one where you plug the 30a power cable into a socket before getting on the road, after disconnecting from shore power, can I assume there is no transfer relay?

That's the configuration my old SOB had - the onboard 30A outlet was powered by the generator.

Ed has a very good point. If you do not know exactly what you are doing leave it alone.

The jumpers I made are actually 3 pieces of 3/8 copper tubing. If I use them I will remove the input and output wires from the transfer PCB completely and use the tubing to butt splice the 3 main conductors directly to each other. Insulated with rubber hose they will provide a direct bypass of the entire transfer system.

quote:

Originally posted by Rusty:
That's the configuration my old SOB had - the onboard 30A outlet was powered by the generator.

That is what I was going to ask Tom. When you do not plug in the 30 amp plug to the internal socket, you will have no AC power, even if the generator is running? Then yes, there would be no transfer relay in the system.

My 50 amp system

This was what I had, I replaced the Xantrex inverter/charger with a Magnum unit after the Xantrex unit failed and I couldn get no help from Xantrex

quote:

Originally posted by Tom and Julie:
So, if this coach is one where you plug the 30a power cable into a socket before getting on the road, after disconnecting from shore power, can I assume there is no transfer relay?

You can. You are the transfer switch.