Running aircon from 16A supply. More advice?

[ARE]

There is a 3rd problem as well. When I bought the unit, I wasn't told that to connect the charger section of the Multiplus to the generator, I needed an extra generator control module. So when I switch my gennie on and I want to charge the batteries, I have to remember to switch on the original charger fitted to the boat.

That's not correct, A multiplus should work directly from the generator output, exactly the same as it should from the shore connection. I have a Multiplus in my motorhome and the only thing I need to adjust is the input limit from the shire line to maximum generator current. There can be some compatabilty issues between Multiplus's and different generator makes, but you can open up the parameters within the Victron to over come this.

Anthony

 

[MapisM]

No marina office or marinara has ever been interested even for my own annual berth. They just say, "up to you" or shrug, or once "the socket doesn't have your boats name on it".

Well, I've not been in Croatia in the last 6 years.
And even if I agree that Croatians never won any user friendliness context, maybe their attitude got even worse than I remember. Or maybe we just met different people, I'm not sure.
I didn't spend much time in marinas around there, anyway. The main reason for cruising the Croatian coast is the endless availability of sheltered bays for overnighting, which in turn avoids any sockets discussions...

 

[Deleted User YDKXO]

That's not correct, A multiplus should work directly from the generator output, exactly the same as it should from the shore connection. I have a Multiplus in my motorhome and the only thing I need to adjust is the input limit from the shire line to maximum generator current. There can be some compatabilty issues between Multiplus's and different generator makes, but you can open up the parameters within the Victron to over come this.

Anthony

Sorry but I don't think you are correct. The manual for my Multiplus clearly states that I need a VGM (VE Net Generator Module) device to operate the Multiplus with the generator and that was confirmed by the Victron installer as well. I don't have this module and it is an extra cost item

 

[Forty_Two]

I have a VE Net controller http://www.victronenergy.com/panel-systems-remote-monitoring/ve.net/ from which the Multiplus is set up and controlled. As I said I haven't yet explored it fully. Typical bloke problem of not wanting to read the manual
Yes I guess you're right about the chiller start up load. I didn't realise it was going to be as high as that. When you say you use a soft start, what exactly supplies the soft start?

I use the TCI 25C from Danfoss. This ramps up the voltage over half a second & reduces the startup current by around 50%.

http://www.danfoss.com/United_Kingdom/Products/Categories/List/RA/Contactors-and-Motor-Starters/Electronic-soft-starters/TCI-CI-tronic-torque-limiters/fae76a4e-738f-4aa6-89ec-c13d8dcc1eec.html

I have it wired with a four pole switch to put it in circuit whenever I need it. You do have to break into the actual compressor wires coming from the control PCB buts it's not a big job if you know your electrics (and you are out of warantee on the chiller). I can lookup the supplier i used if you are interested, it wasn't expensive as i recall.

I have an 11Kw Onan geny which runs all the aircon fine but if i use the multiplus to charge the house battery from the geny it resets every time the chiller starts as the geny volts drop just below the Multiplus lowest AC volts input setting. Switching the softstart in circuit totally fixes the issue. There is still a large draw for a few milliseconds at startup but its not as extreme.

I don't have that controller just the straight control panel. I use my laptop for any specalised tweaking. The Multiplus is an amazing bit of kit but does take some setting up.

Rather than have it inline all the time mine appears as another source to select on the master AC selector, ie Shore/Off/Geny/Off/Multiplus. That way i always know when i am inverting.

I have an additional 5,000 btu AC unit in the aft cabin which runs very happily from the multiplus on invert overnight, but i do have 1,100Ah of AGM batteries!

Edit: bought the softstart from these people http://www.cse-distributors.co.uk/

 

[RupertW]

The main reason for cruising the Croatian coast is the endless availability of sheltered bays for overnighting, which in turn avoids any sockets discussions...

Couldn't agree more - apart from the start and end of the cruise then every possible night at anchor. I do find with non-boating guests though that they get a little bit antsy if they can't step ashore every other day, so on those trips just have to grin and bear the costs and other hassles.

 

[Deleted User YDKXO]

I use the TCI 25C from Danfoss. This ramps up the voltage over half a second & reduces the startup current by around 50%.

http://www.danfoss.com/United_Kingdom/Products/Categories/List/RA/Contactors-and-Motor-Starters/Electronic-soft-starters/TCI-CI-tronic-torque-limiters/fae76a4e-738f-4aa6-89ec-c13d8dcc1eec.html

I have it wired with a four pole switch to put it in circuit whenever I need it. You do have to break into the actual compressor wires coming from the control PCB buts it's not a big job if you know your electrics (and you are out of warantee on the chiller). I can lookup the supplier i used if you are interested, it wasn't expensive as i recall.

I have an 11Kw Onan geny which runs all the aircon fine but if i use the multiplus to charge the house battery from the geny it resets every time the chiller starts as the geny volts drop just below the Multiplus lowest AC volts input setting. Switching the softstart in circuit totally fixes the issue. There is still a large draw for a few milliseconds at startup but its not as extreme.

I don't have that controller just the straight control panel. I use my laptop for any specalised tweaking. The Multiplus is an amazing bit of kit but does take some setting up.

Rather than have it inline all the time mine appears as another source to select on the master AC selector, ie Shore/Off/Geny/Off/Multiplus. That way i always know when i am inverting.

I have an additional 5,000 btu AC unit in the aft cabin which runs very happily from the multiplus on invert overnight, but i do have 1,100Ah of AGM batteries!

Edit: bought the softstart from these people http://www.cse-distributors.co.uk/

Thanks Forty Two for a really useful post. I am a dimwit when it comes to electrics so this is going to have to be a winter job for when the boat returns to italy. One question though. If a soft start is so useful, why don't the boat manufacturers or the equipment manufacturers fit them as standard on high start up load equipment? Yes I agree that it would be more useful to have Multiplus operation on a separate switch. We went out from the boat a few nights ago leaving the a/c on full power driven by the shorepower. When we came back from dinner several hours later, the shorepower had tripped (a boat problem, not a shore problem) and the inverter had been trying to drive the a/c for several hours. Yes you have a lot of battery power; I doubt whether I have 50% of that on my boat. Thanks again

 

[ARE]

Sorry but I don't think you are correct. The manual for my Multiplus clearly states that I need a VGM (VE Net Generator Module) device to operate the Multiplus with the generator and that was confirmed by the Victron installer as well. I don't have this module and it is an extra cost item

Unless I am misunderstanding the problem, A Victron Multiplus does not need this VE net generator module for the cherger section to work from a generator?

The VE net generator module is designed to start/stop & monitor the generator from the victron panel.

If the charger section of the multi does not work when on generator, it is either the voltage, frequency or wave form that is out of tolerance.

From memory the voltage needs to be between 178v to 278V, the frequency needs to be 49Hz to 52Hz if on factory settings.

A quick test, if you switch the inverter to charge only, the above parameters widen to something like 46Hz to 66Hz and 100v to 300v. If after 30second the charger comes on the issue is setup between the inverter and the generator.

Have you checked the voltage and frequency of the generator with a multimeter?

What make of generator do you have?

Anthony

 

[Forty_Two]

Thanks Forty Two for a really useful post. I am a dimwit when it comes to electrics so this is going to have to be a winter job for when the boat returns to italy. One question though. If a soft start is so useful, why don't the boat manufacturers or the equipment manufacturers fit them as standard on high start up load equipment? Yes I agree that it would be more useful to have Multiplus operation on a separate switch. We went out from the boat a few nights ago leaving the a/c on full power driven by the shorepower. When we came back from dinner several hours later, the shorepower had tripped (a boat problem, not a shore problem) and the inverter had been trying to drive the a/c for several hours. Yes you have a lot of battery power; I doubt whether I have 50% of that on my boat. Thanks again

The problem is the softstart has to be wired in such a way that is a mod to the OEM kit as supplied to any boatbuilder which i doubt they would be interested in as it's only a few cruisers that have this problem. Also it only really applies to chilled water systems as a multiple A/c install has seperate units/compressors so wouldn't normally be an issue. I have heard it can impact compressor life but i have never found a definite answer on that so i just use the softstart when needed which is very rare to be honest.

In fact when we started down here in 2001 we used to run the A/c for two months continously, got more used to the heat now & hate the shut in feeling so only run on days we are not cruising & if ultra hot with no breeze (like this afternoon!). Still we have lots of windows to open & all round white gauze blinds - which are the best thing ever, reduces the load on the A/c when it is running.

In fact my problem is my own fault for specing a single compressor chiller instead of a 2/3 compressor unit which would come on in stages reducing the draw. It's only occasionaly i can't get a 32A or two 16A feeds so not a big issue in Sof or Italy. By the way i would NEVER use the parallel 16A plug idea. For instance my marina uses different phases on sockets in the shore box. Big Bang, very dangerous. Wire something out to a seperate plug ie the chiller, much safer - anyway......

Talk to Dometic, they do supply softstart i believe. These days apparently its much better - there is a system that ramps the frequency up from 0 - 50Hz using a 3 phase chiller.

 

[John100156]

.......why don't the boat manufacturers or the equipment manufacturers fit them as standard on high start up load equipment?......

Mike, a lot of AC units have in-built inverters nowadays for the reasons that you are experiencing and to ensure non-disturbing loads are imposed on the electrical network. It was felt many years ago that problems might be caused with oil circulation or the units may trip on their pressure controls but nowadays this is not an issue, so a soft start makes a lot of sense to me to prevent the very high inductive load taking out the breaker.....

 

[John100156]

Mind you if you can get them to fit a motor rated circuit breaker that allows substantial over current to flow for longer (time/current characteristics) that might also sort your problem to your home supply, mind you then you have to ensure it descriminates with the protective device next in-line or you could take out the whole line. Any decent electrical engineer should be able to advise you in that regard!

 

[Deleted User YDKXO]

Thanks Forty Two

 

[Deleted User YDKXO]

Mind you if you can get them to fit a motor rated circuit breaker that allows substantial over current to flow for longer (time/current characteristics) that might also sort your problem to your home supply, mind you then you have to ensure it descriminates with the protective device next in-line or you could take out the whole line. Any decent electrical engineer should be able to advise you in that regard!

John, my home marina isn't the problem as I have a 32A supply there. Its when I visit other marinas which, in Croatia, tend to have 16A supplies

 

[Deleted User YDKXO]

Unless I am misunderstanding the problem, A Victron Multiplus does not need this VE net generator module for the cherger section to work from a generator?

Anthony thanks for the input but the company who fitted the Multiplus confirmed unequivocally that the Multiplus is only connected to the shorepower supply and not the gennie supply and that the gennie could only be connected via a VGM. Certainly the gennie on my boat does not supply the Multiplus the way it is wired at present

 

[Forty_Two]

Anthony thanks for the input but the company who fitted the Multiplus confirmed unequivocally that the Multiplus is only connected to the shorepower supply and not the gennie supply and that the gennie could only be connected via a VGM. Certainly the gennie on my boat does not supply the Multiplus the way it is wired at present

Sounds like its a function of how they wired it. On mine I have an input selector switch shore/off/geny as I use it as a battery charger quite a lot.

 

[BartW]

Anthony thanks for the input but the company who fitted the Multiplus confirmed unequivocally that the Multiplus is only connected to the shorepower supply and not the gennie supply and that the gennie could only be connected via a VGM. Certainly the gennie on my boat does not supply the Multiplus the way it is wired at present

Mike,
I can confirm that you don't need the VGM module,
I have the multiplus, and NO VGM module, and can charge the batt from shore power OR from the genny, just need to set the supply selector switch in the correct position,

moreover I've never worked with that V-net pannel, I'm afraid they sold you something you don't really need,
we alway's install that simple "Digital Multi controll remote panel"
and that is usefull and needed daily to change the usefull settings.
and have led indications of whats going on


will dig in to this later and try to sort out what you should change.
but already now two important remarks,

1) don't try to run you airco from the inverter (just to help starting is OK if it works), the load is much too high for your battery's.

2) when you go away from the boat, with shore power connected,
alway's make sure the victron is in "charging only" mode,
not invertor,
any electric load, might empty your battery's when the shore power accidently is switched off during your absense

too hot now here in SOF,
in need for a swim urgently

 

[BartW]

I never left my boat unattended with the two pugs connected.
...
And it's pretty obvious that I would have never pretended to be entitled to

.

+1

 

[BartW]

Not sure of what you mean by earth leak detector, though. Do those sockets have individual RCDs (residual current devices)?
If so, it's pretty obvious that the load will never be perfectly balanced, and a 30mA leak is enough to make the typical RCD disconnect.

exactly!
(flamish word used for RCD sounds like "earth leak detector" )

not a "leak"
just unballenced current over the two sockets
but I'm sure you know

 

[Deleted User YDKXO]

Mike,
I can confirm that you don't need the VGM module,
I have the multiplus, and NO VGM module, and can charge the batt from shore power OR from the genny, just need to set the supply selector switch in the correct position,

moreover I've never worked with that V-net pannel, I'm afraid they sold you something you don't really need,
we alway's install that simple "Digital Multi controll remote panel"
and that is usefull and needed daily to change the usefull settings.
and have led indications of whats going on


will dig in to this later and try to sort out what you should change.
but already now two important remarks,

1) don't try to run you airco from the inverter (just to help starting is OK if it works), the load is much too high for your battery's.

2) when you go away from the boat, with shore power connected,
alway's make sure the victron is in "charging only" mode,
not invertor,
any electric load, might empty your battery's when the shore power accidently is switched off during your absense

too hot now here in SOF,
in need for a swim urgently

Thanks Bart but I'm now confused. The Multiplus manual that I have makes no mention of any other type of controller other than the VE Net controller but I see now from the data sheet on the website that there is also a digital control. I was sold the Multiplus as a package with the VE Net at a special price so I'm not sure that a Multiplus with the digital control would have been much if any cheaper. I assume that all functions of the Multiplus can be set from either control?
Yes when we leave the boat I should put the Multiplus on charge only. Can I do that from the VE Net control or can I only do that on the Multiplus unit itself. As I said in my post I'm still finding my way around the unit

 

[MapisM]

not a "leak"
just unballenced current over the two sockets

Yep, absolutely.
I called it "leak" because that's what the unbalanced load would appear to the RCD.

 

[BartW]

- I assume the Victron power assist mode works to start your airco from 16A shore + extra power from the invertor ?

- The max shore current is a setting that you should make yourselves, and can never be detected automatically. No unit can “see” how much current is maximum available.
Actually I never had a problem setting the max current at the NOMINAL current from the trip/fuse in the shore electric pole.

when the genny is running I set it at max (50 amps),

This setting is something you need to change almost daily, so that extra “digital control” remote panel is almost indispensable for that;

Here is a list of features of that remote panel:
* Set the max shore or max genset current
* numerical LED display to show the max current setting
* switch for: invertor on – off- charger only (during night on anker, I switch the invertor off, I have 5 x 230V fridges in the cabins, and these empty my battery’s in one night when its hot)
* indicator leds to show :
if 230V power supply is OK
if the max shore current is reached
if the invertor is working
if the invertor is working in power assist mode
if the battery’s are charging, and in which mode (3modes)
if there is alarm fe Lo battery which we have regulary…

In this remote panel is one more programmable relais, there is one in the unit also, I’m going to use that one for starting the genny automatically. You can use it also for an alarm, ..

If you want I can send you such a digital remote panel, (costs me less then 40 euro iirc)
Its really plug and play with a UTP cable.

- Do you have a 3KW or a 5Kw unit ,
Remember a 3KW unit can only produce 13Amps in invertor mode, so you can never run your airco from the “invertor only” (your airco was 16A iirc ?)
Even if you have the 5Kw unit, (max 22A current invertor mode) might struggle with the startup current.

- The Victron can DEFO run on a Genny, I believe your supplier did wrong cabling of your unit,
Actually it is very simple, the unit should be cabled just “behind” the switch or relays that switches between shore or genny power supply.
For The Victron it doesn’t matter where the supply comes from on its AC input, either genny or shore power.
The only setting that you might need to switch off is the “UPS” mode. In this mode there is no interruption switching from mains supply to invertor mode, but AC supply from certain types of genny’s is not stable enough to achieve that.

- The remote panel you have is handy for system settings and diagnostics, you can display all voltages and currents going in and out, … but not for daily display nor user settings

- The Victron Multiplus is a complex unit, also my crew had to learn how to use it (they still make mistakes with this every now and then.)

I wouldn’t use it the way you do,
I believe you’d better put a soft start on your airco compressor, and then connect all the heavy 230V consumers; airco, boiler, dishwasher, washing machine, ice maker, desalinator, …on the AC2 output from the Victron.
This output doesn’t have the invertor nor power assist supply, it only works when shore power or genny power is available.

Actually in my boat, only the 230V sockets in the cabins and saloon are connected to the AC1 output (can run on invertor),
While still having the max current management and setting available (AC1+AC2 output) to avoid overload or tripping the shore supply.

Last winter I had a Canados electrician do some works on BA in his free time; ao; installing the decklights, power supply for the hilo platform, rewiring the Victron, …
I had a hefty discussion with him about how to wire the Victron, Initially he didn’t want to do it like I asked, then two weeks later he came to excuse himself, and fully agreed with my setup, after reading and thoroughly investigating all features of the Multiplus.