Turbo-charging Motorhome Electrics

[wildebus]

I bought an used Autotrail Cheyenne Motorhome (see Not a Self-build, but a Tweaker to see my new baby ) and one of the things I always intended to do was update and improve the Habitation Electrics.
I knew no factory-made Motorhome would provide what I wanted, so no matter what I bought, I'd need to update, and the general other features of the Cheyenne were just right for our needs, so a perfect base for upgrading.

This will be a multi-part post, and the first part is to scope out the target plan

Part 1. What is fitted and what the general target is?

What's Fitted?
The Autotrail Cheyenne is a fairly high-end Motorhome and is fitted with some reasonable Electrics.
It has a Sargent EC325 Power Distribution which is a fairly nice unit with integrated 12V fusebox and wiring, plus a 240V integrated Consumer Unit with 3 MCB circuits. This unit also has a comprehensive control panel with tank info, switchable selection between Leisure and Vehicle batteries and a Charger that operates both on Hookup and Alternator. This is a handy Multi-stage charger that works on both Alternator and Hookup and genuinely does go into a Bulk and Absorption mode at 'proper' voltage levels before settling into a Float mode
The downside of this unit is the very limited capacity of the charger, maxing out at under 10A charge rate when either Driving or on EHU.

Fitted to the Cheyenne was a pair of 100Ah AGM Batteries, which sound ok but actually were worn out and in desperate need of replacement.

The previous owner, who had the Motorhome from new, never fitted any roof-mounted Solar but carried a portable panel.

There was no off-grid 240V available. That's pretty typical for a Motorhome of course, but I wanted to be able to use 240V at any time, so an Inverter would be needed. This would be for convenience things like Laptop Chargers, Microwave, Slow Cooker, small Induction Hob, and the like. Needed? No. But these are things that are good to have access to when you want them IMO.

I also want a reasonable length of time to be able to be off-grid/wild camping, so a decent sized Battery Bank is needed and of course depending on the time wanted to spend off-grid will factor into the amount I use the Inverter and when needed simply revert to other options to the electric cooking tools to extend that time. But if power is there, use it and save gas
Flexibility is the name of the game


So the target...
First was choosing the new batteries to replace the pair of AGMs. Originally I was looking at Lithiums (and specifially the very attractive Poweroad Infinity LiFePO4 models) but for the capacity I wanted and the other items I needed to get, they were above the available budget, so I instead selected the Ritar (Expedition) Lead-Carbon 100Ah Batteries. These batteries, again from Alpha Batteries, are an excellent battery with very usuable capacity and high charge-cycle count and under a 1/3rd the price of even the well priced Infinitys .
So into the Motorhome went 3 x 100Ah Lead-Carbons, offering a perfectly usable >240Ah capacity but stil retaining a better cycle count then AGMs taken down to only 50% DoD for example. As a trade partner of Alpha-Batteries, I was able to secure these batteries with a discount but that did not influence my selection, having had excellent experience of a different brand Lead-Carbon Battery Bank in my Campervan .

To provide EHU Charging Service and Inverter, I chose a Victron EasyPlus 12/1600/70. This incorporates a 1300W Inverter (so covers all the 240V products I might want to use) with a 70A Charger (The bank of 3 batteries can charge at a rate of 30A/Battery, so a 70A charger is a nice match for the bank). The EasyPlus is a combination of a MultiPlus 1600 with a 240V AC Distribution Setup built into it. There would seem to be a degree of duplication with the Sargent, but in fact this extra feature in the EasyPlus compliments it well, allowing extra features and flexibility (to be covered later) to be incorporated into the build and for some strange reason can be sourced at a lower price than the straight Multiplus 12/1600/70 .

The EasyPlus Charger takes the over the function of the Sargent EHU Charger, and so giving a charge rate of upto 70A rather than the original 10A - a massive advantage of course. I decided to marry a Battery to Battery (B2B) unit to that to take the place of the Sargent Split-Charge unit, and chose the Ablemail AMC 12-12-60 60A Battery to Battery Charger. This is a perfect companion to the Multiplus and a great match to the Ritar Batteries .
Whilst I would have chosen this B2B for my installation anyway, having had excellent results from its smaller 30A brother on other installs, for this installation I was fortunate to be gifted this unit by Merlin Electronics, producers of the Ablemail products .

For Solar Charging, I will have a PV Array permanently mounted on the Roof, going down to a Victron SmartSolar MPPT 100/20 Controller. This controller is good for upto 290W of PV and the plan is to have 270W on the roof, so a perfect match (and as it happens, a Controller I happen to have kicking around, which is very handy )

To complete the picture in terms of components, I will be adding a Victron Cerbo GX 'communication centre' that the EasyPlus, SmartSolar and a BMV-712 Battery Monitor will connect to to collate the data from all the units and feed the Victron Remote Management Portal as well as allowing remote monitoring AND remote control of the electrics in the Motorhome.


So this is the Goal and will give my Cheyenne Motorhome a very good level of extra flexibility and usability.
Adding the kit above is pretty easy. Doing it neatly in a such a way to not stand out like a sore thumb in the traditional appearance of the Motorhome interior (and I do find the interior design of the Cheyenne very attractive in fact and don't want to mess with that in a 'unsympathetic' way) is another matter and the install will be the next stage.

 

[wildebus]

Part 2. Installing the Kit

Breaking this into logical chunks now ...

Batteries. The Autotrail Cheyenne has a good sized external battery locker that currently contains a pair of 100Ah AGM Batteries. I was thinking of using that to fit a pair of new batteries (initially Lithium being the plan, but changed to Lead-Carbon) in the same place, but after playing around with ideas and options, using battery mockups made from Cardboard (a lot lighter to move around ), I decided to install inside the living space.
The weight aspect was a consideration - 60kg hanging on a strap is a fair weight and I tend to be fairly cautious when it comes to fixtures and fittings); Cable lengths and routing internally would be a lot shorter and tidier; I could use the external locker for other things that I maybe would not want to carry inside (my frontier stove is a good example ); and also, going inside would allow me to have an extra battery if I wanted.

This is one of the batteries. What I found slightly unusual on these compared to other lead batteries I have installed - and a distinct advantage - is that the top is flat. This means you have have a cable going from battery to battery in a straight line rather then having to route it and twist it around a raised section by the terminals.

Not got a photo of the batteries just in position to show them, so this is with the inevitable cable nest on top

So three batteries in parallel, with short interconnect cables. I am mosting using cables I had knocking around for this in fact. For this setup I would use 25mm2 cable minimum as interconnects, but am in fact using 50mm2 as that is what I had handy - so pretty chunky! The battery bank is protected by a MegaFuse (the black block on top of the middle battery with a 225A Fuse fitted) and then goes to a switch to allow the bank to be disconnected from the system.


EasyPlus Charger/Inverter. The Victron EasyPlus is fitted on its back between the battery bank and the front of the storage section

Three categories of cabling goes into the bottom of the EasyPlus ...
1) 240V AC Cables - these are the Orange, Blue and Yellow mains Flex. The typical Multiplus has just one or two AC cables out, depending on which model it is. But with this EasyPlus, there is one incoming AC Cable in and actually FOUR AC Cables out! I'll cover this more later on why there are 4 and how they will be used.
2) 12V DC Cables - There are a pair of 35mm2 DC Cables (one Red + one Black). The +ve Red goes to the Master Switch mentioned on the battery section & the -ve Black goes to the BMV Shunt.
3) Control/Data Cables - There is a Temp Sensor pre-fitted and a cable from the internal connection goes to the sensor (interestingly, I am NOT going to use that sensor as cabled); There is an RJ45 Cable fitted, connected to the VE.Bus port inside the Unit - this will go to the Cerbo; And the final cable is the white cable coming out and currently I don't have a use for. This is wired to an internal relay in the EasyPlus and I wired up the cable as if I do find a use for it, it will be a lot easier to connect it up that way.


The other remaining devices will be mounted on top of the EasyPlus, but in order to be able to secure those device and also have the EasyPlus servicable and keep enough airspace around for ventilation.
In order to do this, I just made up a removeable platform from Ply (the vertical side will actually go between the EasyPlus and the Batteries)

This slides into place, supported by modesty blocks attached to the storage area sides and then screwed down to stop it moving.


Other Devices. Covering the B2B, MPPT, Cable Protection and Monitoring now ...
Secured to the Plafform above are the various devices mentioned

Listing devices above:
BMV Shunt: This is for the BMV-712 Monitor. Got the Easyplus -ve Cable and a fusebox -ve going to the LOAD side of the Shunt, with the BATTERY side having a single connectiom, that being the battery bank.
1+2 Way Switch: I used this switch to allow me to be able to isolate the Battery Bank AND isolate the EasyPlus (switch Position OFF); disconnect the EasyPlus from the Battery Bank & Hab System (switch Position 2), or to disconnect the Hab System from the Battery Bank, but keep the EasyPlus connected to the Battery (switch Position 1); OR - and this is the the default operational setup - have everything in play (switch Position 1+2).
This just adds useful potential flexibility for servicing needs.
Midi Fusebox: Using this to distribute DC power in a protected centralised way with suitable fuse protection (I flinch when I see these installations which have a big stack of cables on top of the battery +ve terminal ). This box gives a nicely managable setup in a neat way (my cabling may go over the box but it is well secured and easy to work round)
Victron SmartSolar MPPT 100/20: The Solar Controller is in place and wired up apart from the PV cables. These are routed but will be connected when the PV panels themselves are ready to be fitted. I am using the Load Terminals on the 100/20 currently to run to a
Ablemail AMT 12-12 Intelligent Battery Maintainer: This keeps the Starter Battery maintained using a pulse charge of 3A every 20 seconds of so. There is no specific need to use the Solar Controllers Load Terminal.
I have the MPPTs LOAD connection set to be always on, so this means that it does not only work when there is solar but works as a direct passthrough connection and is just a convenient way to connect as well as allowing me (geek alert) to use the SmartSolar to monitoring the LOAD current and see how the AMT is working.
Ablemail AMC 12-12-60 B2B Charger: The Ablemail AMC 12-12-60 is a Multistage Battery to Battery Charger with an output of 60Amps at whatever output voltage is configured. This specific model is setup for a 12V Starter,12V Habitation configuration
The B2B was maybe the most awkward of the devices as needed to get a cable from the Starter Battery to the B2B (could not rely on any existing cable as the factory installed setup ran at significantly lower currents and Motorhome manufacturers are not reknowned for using oversized cables!).
Photo below shows the Starter Battery +ve Terminal. All the standard fused lines are in use, so I picked up the corner one and added an in-line Fuse holder (with 80A Fuse) a few cms after the battery connection.

Victron Cerbo GX: This is the Heart of the system monitoring and there are cables from the EasyPlus (VE.Bus), BMV-712 and MPPT (VE.Direct) into it, plus a couple of Relay outputs and a couple of Temp Sensor connections (more on these later), plus a GPS Dongle.

So that covers all the devices installed in this storage area. There are lots of cables needed to be routed here and trying to do that neatly was certainly a challenge! The Autotrail routing of cabling used a void the went from the corner top locker down to under the van and then routed in various directions. I looked at utilizing this route but ultimately discounted it and went a different way
Decided to use the void within the Cab B Pillar instead. Autotrail puts a trim piece over the pillars, so it was a matter of removing the trim, running the cables within the void (making a hole in the side of the storage area that would be hidden by the trim) and then replacing the trim.
I don't have a 'work-in-progress' photo for the cabling, but this is the B-Pillar after the cables are routed and the trim replaced

You can just see a hole with a black and red cable poking out - that is the cabling from the Starter Battery. I was actually going to make a cover to follow the line of the bottom dark grey moulding to cover this , but the original trim adapted so closely I'm sure if I will bother as that part is hardly visible anyway?

And finally, back to the Storage Area and what does it look like now? Well everything is inside one side of the Storage area and I can lift up one cushion to see inside and access the Isolation Switch, as well as accessing the EasyPlus controls and Breakers by dropping down the front hinged flap.

So that completes the Physical Installation. The next post will be how it actually works together and how I am dealing with system duplication i.e. AbleMail B2B and Sargent Split-Charge, and EasyPlus Mains Charger and Sargent Mains.

 

[Millie Master]

Not wishing to put a dampener on your efforts Dave, and I am sure you have taken this into account being the thorough man that you are, but the vast majority of flimsy pro built motorhomes have a relatively low load margin and all your extra kit will be eating into the margin with a voracious appetite.

Phil

 

[wildebus]

Not wishing to put a dampener on your efforts Dave, and I am sure you have taken this into account being the thorough man that you are, but the vast majority of flimsy pro built motorhomes have a relatively low load margin and all your extra kit will be eating into the margin with a voracious appetite.

Phil

This add an extra 50Kg 65Kg when the Solar is added. This is one human body and I only travel with one other Human at the most, rather than a family.

When I get round to it, I will do the forms to get the GVW raised to 3700 (extra 200Kg).
I might at a later time go to 3850Kg and possibly 4000Kg (all totally doable on this chassis with minor DIY suspension changes).
I got a brand new set of Michelin Cross-Climates with a higher load rating already to make sure all is safe.

 

[xsilvergs]

@wildebus Nice looking Midi Fusebox (from the image), do you have a link to supplier (or is it you)?

 

[wildebus]

I can supply them (I get them in in bulk for build kits) but they are available from a few sellers and TBH, the cost of the postage means I would charge more
This seller is good and well priced - https://www.ebay.co.uk/itm/4-Way-Ca...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649
You get 4 or 6 fuses included (depends on seller) and need two different allen/hex keys (not supplied) to fit. I like them as they work well and you can change fuses without disturbing the cables.

 

[wildebus]

Part 3. Original Electrics cohabiting with new Electrics

As mentioned, I want to use the original electrical setup where appropriate and use the new components in conjunction.

Split-Charge.
The Cheyenne has a multistage powersupply in the EC325/328 PDU - this works on both AC Mains and DC Alternator. Quite a clever idea it has to be said - but the downside is the very limited output, which sadly makes it of very little use for either purpose.
The function of the built-in 10A DC-DC Charger is therefore being replaced by the Ablemail AMC 12-12-60 60A Battery to Battery Charger.

What was needed in order to make sure the new B2B was not confused by another charger running in parallel was to disable the built-in unit. There are a few potential paths, but which is suitable depends on how the Sargent kit has been wired up by Autotrail.
The Motorhome has as part of the installation an auxilary control unit from Sargent - an EM50 Intelligent Interface Adapter - used for various functions. One of those is potentially for the Split Charge (see picture below)

As can be seen, Fuse #8 is meant to protect the Split Charge Supply. So removing Fuse F8 disables the Split Charge? Um, no. It makes no difference (but I guess the ** does say 'Depends on vehicle specification' )

What I needed to do wtrh the Cheyenne was to use an alternative control input instead
There is an 'Engine running signal' on a connector block coming into the Sargent PDU (pin #9), as noted in the diagram below

Diconnecting this signal stops the integrated Split charge working - so that fixes that problem.
However, there is more then that function that happens when the engine starts - so what about those? It is important to know the full consequences...
Other key functions are

1. The 12V supply to the Fridge that activates when the engine runs;
2. The door step automatically retracts; and
3. The Habitation Electrics get turned off.

#1 is a key function. Fortunately the way the Sargent is wired as standard there is a relay outside of the PDU that activates when the Engine Starts (activated by the D+ signal) and the output of that relay goes to both the Fridge AND the Engine running signal to the PDU. So removing the input to the PDU has no impact on the Fridge
#2 is very important as well. It is possible to press a button to retract the step but for safety reasons, an automatic retract is very desirable. This function is managed by the EM50 and I have made no changes to that, so this continues to work as before
#3 is an interesting one. Having the habitation electrics disconnect when the engine starts is not always a great idea. They also don't reconnect by themselves when the engine goes off. By disconnecting the Engine running signal into the PDU, this auto-disconnect no longer occurs. Generally, I regard this as a plus actually, as it allows me to chose to leave them on, or to disconnect using the button that Sargent provide on the Control panel


Mains Charging.
The Sargent PDU allows you to charge either the Starter Battery or the Leisure Battery by selecting which battery is being used on the control panel and turning the Charger switch to on. Doing this will activate a 10A multi-stage charge.
The new setup with the EasyPlus gives a 70A charger, but this will only operate on the Leisure Battery.

It is easy however for me to charge the Starter Battery still. When on EHU, I can still select the Starter Battery from the Control panel and turn on the Sargent Charger. This will result in having the 10A integrated charger working on the Starter Battery and the 70A EasyPlus charger working on the Leisure Battery.
If I don't switch to the Starter Battery, I will just leave the Integrated Charger off, and the Ablemail AMT 12-12 Battery Maintainer will put a pulse charge into the Starter Battery. Generally this method will be sufficient to keep the Starter Battery at around 12.8V unless there is a reason why I need to do a 'proper' charge into the Starter Battery. I think it is a good idea to periodically do a full charge on the Starter Battery for extending the service life of these, so I would probably set the switches to do the EHU Starter Battery charging process once a month or so.

Solar Charging.
There is no Solar setup installed, so nothing to integrate with the existing setup. The Sargent unit does have a Solar Controller built in probably (I say "probably" as they did originally, but I understand they get removed sometimes when serviced or upgraded) but they are limited to just 120W so I would not be using that anyway.
So the Victron MPPT will take care of this and similar to the Mains Charging, the Starter Battery will get a pulse trickle charge while the Leisure Battery gets its normal charging from the PV Solar Panels.


That pretty well covers the co-existance with the 12V Side of the Electrics. Next will be the 240V side....

 

[wildebus]

Part 3. Original Electrics cohabiting with new Electrics (cont).

Covered the 12V DC side in the last post. Now I'll cover the 240V AC (or 230V AC for younger viewers )

The Factory Sargent EC325/328 includes a Consumer Unit with incoming RCD and 3 MCBs - one general use, one dedicated for the Truma Ultraheat Heater and one for the AC Lights, Battery Charger, Water Heater and Fridge.
I am using the CU features of the EasyPlus to add flexibility to the existing AC setup. Some of this will be in the future so is in my ultimate plan but cables are routed ready to fit, so just half a days work basically.

What is the target?
Want to be able to use the general sockets off the inverter whenever I want to - so stuff like Laptop Chargers, AC Battery Charger, little Induction Hob, Slow Cooker, that kind of thing. Obviously there is a need to make sure there is enough battery capacity for this.
The Truma Ultraheat in Electric mode is not really something I expect to run off the Battery Bank
The Water Heater and Fridge are ones which could be useful to be able to run off the Batteries in the right circumstances as they are either short bursts of higher power (Water Heater) or extended times of lower power (the Fridge). This would work well at times of good Solar Harvesting where for extended periods of the day, all or most of the enegy the fridge wants could come from the PV Panels.

How to achieve this in a simple way? or at least, in a simple way to use if not to initially setup anyway
Here we go ...

To the EasyPlus, I ran a fresh cable from the Hookup External Plug to the AC In
Coming out, there is an RCD going to four separate breakers (MBC 0 to MCB 3)

MCB 1 was cabled to connect to the original Cable that goes to the Sargent PDU. As it stands, that is how things are running and the remainder will be changes and updates.
This breaker is driven by EHU OR Inverter

MCB 3 is a brand new addition to the electrics. This will go to a dedicated externally accessible socket. I have a socket like this on my Campervan and while I don't use it a lot, when I need it, it is really handy to have. LIke MCB 1, this is EHU or Inverter driven.

MCB 0 and MCB 2 are the interesting ones.
MCB 0 is an output that is only live when there is an live input into the EasyPlus. Unplug the EHU power and MCB 0 goes dead. This makes this ideal as a source for the Ultraheat Room Heater as there will be no risk of draining the batteries if the power is lost. I will in the future be connecting the cable that goes from MCB 0 to the cable that goes to the Room Heater.

MCB 2 is an output like MCB 1 - It is live on Hookup or Inverter.

What I have done is use an auto switching relay that has two sets of inputs - one from MCB 0 (so mains only) and one from MCB 2. The delay is by default on MCB 2, but if it detects power on MCB 0 (so live AC in), it will switch to that. This means it will always use direct mains when available, but when not, will use the MCB 2 source.
The output of this auto switching relay will then (once cabled up) go to both the Fridge and the Water Heater

The next step to this is to have an AC SSR (Solid State Relay) between MCB 2 and the auto switching relay. This allows the MCB 2 input to be disconnected via a 12V DC control line, so if I want to, I can remotely disconnect MCB 2 if say I think the Battery Capacity remaining is getting a bit low.
What I can now do is connect that control line to a programable relay on the Victron Cerbo GX. This relay can be configured to go active/inactive depending on a variety of parameters. I am using the SoC (State of Charge) parameter to have the relay active once the State of Charge hits a chosen value. This way, you can automate how the Fridge and/or Water Heater will come on and off depending on what battery capacity you want to keep in reserve.
Fort example, in the summer, you might find the solar is very effective and you can afford to have the battery drop a bit as you know you will make it up the next day. And in winter, you know you will have more lights on for longer, and the heater fan on, plus solar won't be recharging the batteries, so you adjust the SoC value so you disconnect at a higher level.
This automated and intelligent use of available battery power, driving appliances like an AES equipped fridge which will use the AC input, and if that drops, switch to gas, will give the best use of the cheapest available power in a seamless manner.
This is the plan anyway!

This is what the Auto Switching Relay and SSR with its cabling looks like in 'real life'

I'll be tieing up the cable connections to Heaters and Fridge at the same time as installing the PV Solar Setup. The two really do go together in terms of usability.


This pretty well finishes my thread on the electrics update. I think the key aspect for this was to select componentry that match up and compliment each other.
So the battery capacity of 300Ah (3 x 100Ah) will give flexibility to drive stuff like the Fridge when backed up with a suitable Solar Array (which will be 90W of panel per 100Ah of battery - again a good match up).
The Victron Easyplus Charger output of 70A gives an average 23A/Battery, which is a nice match to the Batteries quoted 30A max charge rate.
Similarly with the Ablemain 60A B2B Charger at 20A/Battery (which allows the Alternator to have reserve to drive the Fridge on 12V mode when driving, which is on a different circuit).

Any questions on this thread and installation, please ask

 

[wildebus]

Not made any changes since the post above. Still got stuff to do but it can generally wait until ready to fit the Solar Array and route the cables through the new holes, etc. (that way only one set of mess to clear up).
Will be having a little play with trying to adapt the Sargent method of water and waste tank reading to the Victron requirements for a bit of fun


In the meantime I have been looking at what kind of overhead the Multiplus has in the system generally. As we know, there is an inherent inefficiency in any device that converts from one power to another (be it an Inverter, a Charger, or a little 12V-USB socket) and knowing how much and the best way to manage it is key for getting the best from your overall Leisure System.
The below screenshot shows how much power is getting drawn by my Motorhome whilst just being parked up and the Multiplus in different modes. I made changes to the setup remotely so between each settings change I didn't open the door and go inside or even unlock the vehicle - so the difference in power is purely down to settings changes in the Multiplus. (note there are no actual AC loads active at any time in the timeline shown)

If anyone is interested, I can do a post on setting up the Multiplus and the different Inverter setup options (and some potential gotchas).

 

[xsilvergs]

Not made any changes since the post above. Still got stuff to do but it can generally wait until ready to fit the Solar Array and route the cables through the new holes, etc. (that way only one set of mess to clear up).
Will be having a little play with trying to adapt the Sargent method of water and waste tank reading to the Victron requirements for a bit of fun


In the meantime I have been looking at what kind of overhead the Multiplus has in the system generally. As we know, there is an inherent inefficiency in any device that converts from one power to another (be it an Inverter, a Charger, or a little 12V-USB socket) and knowing how much and the best way to manage it is key for getting the best from your overall Leisure System.
The below screenshot shows how much power is getting drawn by my Motorhome whilst just being parked up and the Multiplus in different modes. I made changes to the setup remotely so between each settings change I didn't open the door and go inside or even unlock the vehicle - so the difference in power is purely down to settings changes in the Multiplus. (note there are no actual AC loads active at any time in the timeline shown)
View attachment 3230

If anyone is interested, I can do a post on setting up the Multiplus and the different Inverter setup options (and some potential gotchas).

Do you know what causes the step change from -17.5W to -10W and then the noisy bit before going to -22.5W?

Not sure I need to know about the Multiplus but I would be very interested in your setup for the Easyplus which may be on my Christmas list (not this year sadly).

 

[wildebus]

Do you know what causes the step change from -17.5W to -10W and then the noisy bit before going to -22.5W?

Not sure I need to know about the Multiplus but I would be very interested in your setup for the Easyplus which may be on my Christmas list (not this year sadly).

I do indeed

PS. I posted "Multiplus" but I do actually have the Easyplus and that is what this graph is from. The two are identical except for the additional add-on AC Breakers on the Easyplus.

 

[SquirrellCook]

Not made any changes since the post above. Still got stuff to do but it can generally wait until ready to fit the Solar Array and route the cables through the new holes, etc. (that way only one set of mess to clear up).
Will be having a little play with trying to adapt the Sargent method of water and waste tank reading to the Victron requirements for a bit of fun


In the meantime I have been looking at what kind of overhead the Multiplus has in the system generally. As we know, there is an inherent inefficiency in any device that converts from one power to another (be it an Inverter, a Charger, or a little 12V-USB socket) and knowing how much and the best way to manage it is key for getting the best from your overall Leisure System.
The below screenshot shows how much power is getting drawn by my Motorhome whilst just being parked up and the Multiplus in different modes. I made changes to the setup remotely so between each settings change I didn't open the door and go inside or even unlock the vehicle - so the difference in power is purely down to settings changes in the Multiplus. (note there are no actual AC loads active at any time in the timeline shown)
View attachment 3230

If anyone is interested, I can do a post on setting up the Multiplus and the different Inverter setup options (and some potential gotchas).

So what loads do you have on the system? A standby overhead of 10 watts is quite hefty.

 

[xsilvergs]

So what loads do you have on the system? A standby overhead of 10 watts is quite hefty.

I'd give my right arm for 10 Watts, I'm over twice that, router, RPi and a couple of D1 mini's

 

[wildebus]

So what loads do you have on the system? A standby overhead of 10 watts is quite hefty.

I haven't parked up and checked all unneeded devices are off. So what is running is the Cerbo, a surveillance camera, the TV Ariel Booster (I think) and MiFi Power. 10W is actually not bad for that lot.

 

[Silver sprinter]

Dave thanks for all your posts and taking the time and details you go into in all your posts, much appreciated, gerry

 

[wildebus]

Been playing around a bit with the Ablemail AMT Battery Maintainer today.

The AMT Unit works very well generally, but I have fitted a fancy new headunit in the cab and one of my Drive/Camping Radio kits.
When in 'Camping' mode - which allows you to use the radio without the key in the ignition - I noticed that there is quite a draw on the Starter Battery even when the radio is turned off. This is because many new head units are never really off when the Accessory +12V is active and they are always drawing power with active bluetooth and the like.
The idea for these Drive/Camping kits is to flick the switch to Camping when you want to listen 'keyless' and once done, flick the switch back to 'Drive', but if you were to leave in Camping (or you have an installation where the radio goes on without the key regardless) then you could get a draw greater than the battery maintainer is expecting.
This is the kind of effect I would normally expect with the AMT in the system. Voltage creeps up to around 12.7V or so as the Battery Maintainer pulses on and off (generally around 15 seconds off, 2 seconds on).

The above is with the Radios Drive/Camping switch in the normal 'Drive' position.
When I put it into 'Camping', even with the radio off (on the units front panel control), there is a degradation of the voltage that the normal setting of the AMT cannot compensate for.

I reprogrammed the AMT to change the 'Pulse on' duration to be longer and reviewed the results ...
uploaded the settings at 13:30 and in the screenshot below I am including a few minutes before the update to show how it affected the voltage.

The new settings have halted the voltage slide and it is now increasing again, albeit very slowly. I'll probably reprogramme the AMT again to give it a faster trickle, but bear in mind of course that this is compensating for a significant pull on the starter battery that shouldn't really be allowed to continue without investigation (I know the reason here of course and can flick the switch back to eliminate it, but some vehicles have their head units badly wired and the owner may be stuck with this situation without realising it).

The ability to do this adjustment is the great thing about an intelligent programmable maintainer like the Ablemail AMT 12-12. It can be tweaked as required without any need to change or buy different hardware.

 

[wildebus]

Not wishing to put a dampener on your efforts Dave, and I am sure you have taken this into account being the thorough man that you are, but the vast majority of flimsy pro built motorhomes have a relatively low load margin and all your extra kit will be eating into the margin with a voracious appetite.

Phil

Went to the weighbridge on the way home from the garage....
van sitting dead on 3.5t

trouble is that is without me being inside it
So I either need to get the remote control installed or do an uprate!

This of course was no surprise as the normal payload is pretty small without the Awning, Towbar and Bikerack fitted, so with those in place plus the new electrics it was always going to be inevitable.
New Tyres were fitted last month (think last month?) with increased load rating and auxiliary Air Assist kit has been ordered to both improve ride & handling and allow higher weight rating so that will bring everything nicely back in line

 

[Millie Master]

Went to the weighbridge on the way home from the garage....
van sitting dead on 3.5t

OUCH, so back to plan Z is it Dave?

 

[wildebus]

OUCH, so back to plan Z is it Dave?

Not at all. Plan A
Buying Lead Carbons instead of Lithiums saved me well over £1,000 but cost me around 45kg. Getting an extra 350kg added to the GVW will cost me a fair bit less than that
Paperwork has been in place for nearly a month ready to be activated

 

[Markd]

Don't know how far on with your up-plating but if you want to go above manufacturer's plate I can recommend John Ruffles of JR Consultancy.
He's a lot cheaper than SVTech if a little harder to get hold of sometimes as he alternates between 2 addresses.

Mr AHJ Ruffles (calls himself John)
company is JR Consultancy
tel: 01359 250808 / 01244 544 598
truckcon@outlook.com