maxtorque
Hi all,
Amazing to say, we've now had our GC600 for a year! it's been all round scotland, Orkney, Skye, the Caingorms, Northumberland, South, mid and north wales, devon and cornwall, and over through France, Belgium, Germany, Denmark, Norway Finland and Sweden. Safe to says it's now run in!
And after this full year of travelling and some 20,000 miles, i think i have the on-board electrics finally working as they should! Getting to this point has been a bit hit and miss but it's now a very comprehensive system, something ime, VW should be fitting as standard these days!
The fundamentals are
1) no gas, we have the Truma heater with the diesel fuel option and i hate having gas cyls and naked flames in the van, so we made the immediate descion to ditch the gas. Modern lithium batteries now have enough energy desnsity and low enough cost to make cooking off 'lecy possible.
2) it must be OFF Grid for at least 3 days. The limit we knew would be water, which in the GC with relatively small fluid tanks means that we were talking about being able to run all our electrics and cook for 3 days without having to start the engine to charge batteries even in winter (no sun)
3) enough 240v power to run anything we wanted in the van, ie toaster, induction hob, hoover or any tool to fix it.
4) the system should be as small as possible to not take up any more space, as the GC600 is NOT a big van
So, we ended up with the following
5kWH of 24v lithium batteries, housed in the rear o/s cupboard where the gas used to be. Mounted on custom alluminium mountings for security. We didn't want batteries to be outside or underbonnet, as lithium batteries are very like people in their temperature demands, so if the people in the van are at a comfortable temperature so are the batteries! Because we had dual gas cyls in this cupboard, and the batteries only take up 1/3rd of the space, we have actually gained storage space in this biggest of the rear GC cupboards!
240Vac 3kW output, 24vdc input inverter mounted in the rear n/s electrical cupboard. Interfaced into the original OE 240V wiring so that if the inverter is enabled it drives the interior 240v sockets automatically. If shore power via the EHU is available (ie when on a campsite) then this powers the sockets and charges the batteries (12v starter, 12v leisure and 24v lithiums)
Mounted on a dedicated slide out panel are the system devices required for charging, monitoring and controlling the system. That panel is totally "unplugable" so it can be worked on and tested off the vehicle, and so you don't end up spending days with your head in the small dark cupboard to fix or modify stuff! It slides out on draw slides to provide easy access and yet when retracted it allows the entire system to fit, with the inverter in the single small cupboard!
On that electrical panel are:
Two independant solar MPPT controllers to charge the 24v system.
One receives power from an additional 100w of solar panels stuck to the roof of the van. The GC600 hasn't got a lot of roof space, so fitting big panels here is not possible, i have squeezed in two 50w square panels between all the std windows and vents on the roof. The OE front mounted 100w panel is still in place, with the OE MPPT to charge the OE 12v leisure battery as standard. This onboard solar is just enough to power the systems parastic loads, meaning when parked the system maintains or slightly raises it's SoC, so no danger of the lithium batteries going flat.
The second MPPT controller is wired to a socket on the towbar, where we can plug in an external 400w foldable solar array. This means in summer we can basically run off-grid without limitation, but that array is simply too large to be permanently mounted on the roof
Onboard charger for the 24v lithium batteries. Powered from the EHU feed, this means when we have shore power (at home, on a campsite etc) we can charge our lithium batteries fully
400w DCDC 12v to 24v charger to charge the 24v lithium batteries from the vehicles alternator / 12v leisure battery. This was the hard bit thanks to the complex smart alternator system in the GC, but we now have a system that works well and reliably. If you want to know how this was done, ask and i'll do a seperate post about it - it's complex
100w DCDC 24v to 12v We found that in winter when there is not much sun, we could not keep the OE 12v lead acid leisure battery charged enough. As this runs the fridge and the Truma heater, and all the interior lighting and the std GC display/controller, we found the limit to our off-grid duration was actually the 12v battery not our 24v lithum. When on a proper campsite with EHU, sure, that power feed charges the 12v system ok, but we were spending days off-grid or on sites where being able to literally take any pitch ie those without EHU, mean't we could stop anywhere. So this small dcdc actually is there to trickle power from the 24v lithium and into the 12v leisure battery, but only when that battery falls below a certain SoC. This bit is important and requires careful design, implementation and calibration to work with the smart alternator functionality!
The whole system is from Victron, so it's all integrated with their CerdoGX controller, meaning remote monitoring and a nice touch screen display, which is mounted above the OE display in the wall of the bathroom. There is also various fuses, relays and interface devices to make it all work, mostly mounted on the removable panel.
Some moving around of the OE components mounted on the back wall of the electrical cupboard was required to make everything work, and to allow the fitment of a second AC distro box that houses the additional circuit breakers and relays required and also mounts a single phase electricity meter that reports the consumption on the EHU feed back to the controller (so we can check we are getting charged accurately for EHU on site that now charge you by the kWh)
So, basically this "Just works" allows us to live and cook, off grid in the van, we can be pretty much 100% solar powered in summer, and in winter from our normal driving around.
There are still some improvements to make. We currently cook on a stand alone induction hob, so i want to build an induction hob into the OE GC kitchen unit, this is tricky because of the narrow size of the std sink/gas hob, but i think i now have a nice solution for this (requires me to get the TIG welder out to mod the std stainless sink/hob assy....) And we hate the OE controller / display on the GC, which is buggy, slow and keeps turning stuff off on a whim, so i think we are going to completely ditch the OE display and i'm going to make a custom replacement to integrate everything into one place, but that is a plan for another day....
Any questions just ask away
Amazing to say, we've now had our GC600 for a year! it's been all round scotland, Orkney, Skye, the Caingorms, Northumberland, South, mid and north wales, devon and cornwall, and over through France, Belgium, Germany, Denmark, Norway Finland and Sweden. Safe to says it's now run in!
And after this full year of travelling and some 20,000 miles, i think i have the on-board electrics finally working as they should! Getting to this point has been a bit hit and miss but it's now a very comprehensive system, something ime, VW should be fitting as standard these days!
The fundamentals are
1) no gas, we have the Truma heater with the diesel fuel option and i hate having gas cyls and naked flames in the van, so we made the immediate descion to ditch the gas. Modern lithium batteries now have enough energy desnsity and low enough cost to make cooking off 'lecy possible.
2) it must be OFF Grid for at least 3 days. The limit we knew would be water, which in the GC with relatively small fluid tanks means that we were talking about being able to run all our electrics and cook for 3 days without having to start the engine to charge batteries even in winter (no sun)
3) enough 240v power to run anything we wanted in the van, ie toaster, induction hob, hoover or any tool to fix it.
4) the system should be as small as possible to not take up any more space, as the GC600 is NOT a big van
So, we ended up with the following
5kWH of 24v lithium batteries, housed in the rear o/s cupboard where the gas used to be. Mounted on custom alluminium mountings for security. We didn't want batteries to be outside or underbonnet, as lithium batteries are very like people in their temperature demands, so if the people in the van are at a comfortable temperature so are the batteries! Because we had dual gas cyls in this cupboard, and the batteries only take up 1/3rd of the space, we have actually gained storage space in this biggest of the rear GC cupboards!
240Vac 3kW output, 24vdc input inverter mounted in the rear n/s electrical cupboard. Interfaced into the original OE 240V wiring so that if the inverter is enabled it drives the interior 240v sockets automatically. If shore power via the EHU is available (ie when on a campsite) then this powers the sockets and charges the batteries (12v starter, 12v leisure and 24v lithiums)
Mounted on a dedicated slide out panel are the system devices required for charging, monitoring and controlling the system. That panel is totally "unplugable" so it can be worked on and tested off the vehicle, and so you don't end up spending days with your head in the small dark cupboard to fix or modify stuff! It slides out on draw slides to provide easy access and yet when retracted it allows the entire system to fit, with the inverter in the single small cupboard!
On that electrical panel are:
Two independant solar MPPT controllers to charge the 24v system.
One receives power from an additional 100w of solar panels stuck to the roof of the van. The GC600 hasn't got a lot of roof space, so fitting big panels here is not possible, i have squeezed in two 50w square panels between all the std windows and vents on the roof. The OE front mounted 100w panel is still in place, with the OE MPPT to charge the OE 12v leisure battery as standard. This onboard solar is just enough to power the systems parastic loads, meaning when parked the system maintains or slightly raises it's SoC, so no danger of the lithium batteries going flat.
The second MPPT controller is wired to a socket on the towbar, where we can plug in an external 400w foldable solar array. This means in summer we can basically run off-grid without limitation, but that array is simply too large to be permanently mounted on the roof
Onboard charger for the 24v lithium batteries. Powered from the EHU feed, this means when we have shore power (at home, on a campsite etc) we can charge our lithium batteries fully
400w DCDC 12v to 24v charger to charge the 24v lithium batteries from the vehicles alternator / 12v leisure battery. This was the hard bit thanks to the complex smart alternator system in the GC, but we now have a system that works well and reliably. If you want to know how this was done, ask and i'll do a seperate post about it - it's complex
100w DCDC 24v to 12v We found that in winter when there is not much sun, we could not keep the OE 12v lead acid leisure battery charged enough. As this runs the fridge and the Truma heater, and all the interior lighting and the std GC display/controller, we found the limit to our off-grid duration was actually the 12v battery not our 24v lithum. When on a proper campsite with EHU, sure, that power feed charges the 12v system ok, but we were spending days off-grid or on sites where being able to literally take any pitch ie those without EHU, mean't we could stop anywhere. So this small dcdc actually is there to trickle power from the 24v lithium and into the 12v leisure battery, but only when that battery falls below a certain SoC. This bit is important and requires careful design, implementation and calibration to work with the smart alternator functionality!
The whole system is from Victron, so it's all integrated with their CerdoGX controller, meaning remote monitoring and a nice touch screen display, which is mounted above the OE display in the wall of the bathroom. There is also various fuses, relays and interface devices to make it all work, mostly mounted on the removable panel.
Some moving around of the OE components mounted on the back wall of the electrical cupboard was required to make everything work, and to allow the fitment of a second AC distro box that houses the additional circuit breakers and relays required and also mounts a single phase electricity meter that reports the consumption on the EHU feed back to the controller (so we can check we are getting charged accurately for EHU on site that now charge you by the kWh)
So, basically this "Just works" allows us to live and cook, off grid in the van, we can be pretty much 100% solar powered in summer, and in winter from our normal driving around.
There are still some improvements to make. We currently cook on a stand alone induction hob, so i want to build an induction hob into the OE GC kitchen unit, this is tricky because of the narrow size of the std sink/gas hob, but i think i now have a nice solution for this (requires me to get the TIG welder out to mod the std stainless sink/hob assy....) And we hate the OE controller / display on the GC, which is buggy, slow and keeps turning stuff off on a whim, so i think we are going to completely ditch the OE display and i'm going to make a custom replacement to integrate everything into one place, but that is a plan for another day....
Any questions just ask away
