External 240v hook-up options?

[peteaufc]

I'm looking to install an EHU hookup point under the bonnet next to the starter battery, very similar to @Deaky solution earlier in this thread.

My plan would be to also install a 3 pin hookup plug and ip67 rated consumer unit under the bonnet, then run a single cable through the existing gromits (with appropriate conduit) into the passenger seatwell. My plan would be to connect this to my Renogy 1000w inverter (which will be on rear of driver's seat base in gap before unit) to allow the socket on it to be used when I'm on hookup. My understanding of the Renogy inverter is that it should seamlessly switch between battery and EHU power as and when EHU is connected/disconnected?

I may also look to install a lithium battery charger to allow charging while on hookup as well.

I like the idea of the consumer unit being under the bonnet and not taking up more space under my driver's seat or elsewhere inside.

Are there any flaws in my plan, or any advice that anyone would offer?

 

[TallPaul_S]

Sounds good - the Renogy inverters do have an automatic transfer switch so if you use the AC in port it'll feed from your battery when no AC and will use 240v AC when that's powered up.

Are you going to be just using the socket on the inverter or adding extras?

If you have 240v hookup then you may as well have it charging your battery too!

 

[peteaufc]

Ideal, thanks for the reassurance! My plan it to feed it into the AC port on the inverter.

I'd like to use the inverter to send power to a 2 gang socket (also with a couple of USBs) on it that I would install on the side of my unit. My thoughts were to wire this with a UK plug into the inverter socket which would run a cable to the back of the 2 gang. Unless there is a better/neater way?

If I go with the charger route as well, would I need to run two cables from the consumer unit under the bonnet, or could a single cable run do both the EHU charger and the inverter?

(Sorry, loads of questions!!)

 

[TallPaul_S]

I think the normal set up is to have a separate breaker for the 240v sockets/inverter and for the charger, so 2x 240v cables coming into the van from the consumer unit.

I'm not completely certain around the 240v stuff though, it can get much more complex than run of the mill 12v!

 

[roadtripper]

As I've posted before the inverters that have this function advertised it as UPS and not a full AC transfer switch.

There are different requirements for grounding and safety for floating 240v outputs (running from inverter) and from grounded supply (EHU) that Renogy and other "UPS" inverters cannot do.

Systems with full AC transfer relays like the Clayton can do this safely.

Basic rule of thumb is unless you understand the difference between the two keep EHU and Inverter 240v wholly separate.

Victron's Wiring Unlimited reference covers this very well, in my opinion required reading for anyone working on 12v or 240v systems

7. Ground, earth and electrical safety

www.victronenergy.com

 

[roadtripper]

I'd like to use the inverter to send power to a 2 gang socket (also with a couple of USBs)

This would be massively inefficient as the draw of the USB voltage converters will keep the inverter on - and even idling inverters will waste power quite well.

If you want USB then run that from 12v and make sure it's on a switched circuit so when you leave the van for any length of time off charge they don't drain the battery.

In your case you will need a consumer unit with an RCD and 2 breakers. Use one breaker for any fixed wired appliances (such as a 240v charger) and the other for sockets - that way if you trip one you don't trip the other. You will need the 240v PE (Protective Earth) bonding to a chassis ground otherwise the RCD will not protect you or anyone touching the van if you have a fault.

Keep your inverter 240v and EHU 240v apart. Ideally just plug directly in to it. If you do need to extend it for access I'd advise only have a single socket to avoid overloading it.

 

[Salty Spuds]

Ideal, thanks for the reassurance! My plan it to feed it into the AC port on the inverter.

I'd like to use the inverter to send power to a 2 gang socket (also with a couple of USBs) on it that I would install on the side of my unit. My thoughts were to wire this with a UK plug into the inverter socket which would run a cable to the back of the 2 gang. Unless there is a better/neater way?

If I go with the charger route as well, would I need to run two cables from the consumer unit under the bonnet, or could a single cable run do both the EHU charger and the inverter?

(Sorry, loads of questions!!)

This is ringing all sorts of alarm bells in my head. I’m not familiar with the Renogy or its feed through features, but what kind of protection does it offer on the output side WRG overload/earth fault? It may be perfectly ok, but it feels wrong to me.