Sargent Power Consumption

[Insider]

Hi,

Curious about some electrons..

I have a Forte with a Sargent EC460 PSU. I fitted a Victron BMV712 a few months ago along with new 2xLFD90s. All good and very happy with the result. I noticed last night the voltage was down a bit - 12.67 so had a look and the Victron told me there was a draw of 0.2A. Everything was off and had not seen that before so did a bit of investigating. Pulled all the 12V fuses in the EC460 one by one and no drop in current. However when I turned off the EC460 my current dropped to 0A which rules out a miscalibration of the BMV. Also the voltage recovered to 12.75 after an hour. The control panel was turned off the whole time. Now 0.2A is not a lot but it's 4.8Ahr over 24hours minimum and I had never seen it before. I have a 90W solar panel but it got me thinking is that normal power consumption of the EC460 ticking over. Not worried but would like to know what other people are seeing.

On a different but similar note the EC460 has smart charging for vehicle/leisure battery charging but I have it all directed to leisure battery. I turned off the EC460 the other day for a few hours and noticed the solar was showing 45W. Leisure battery was getting nothing so I think the EC460 was sending everything to the vehicle battery. On the phone app for the MPPT it was showing bulk and the battery was at ca 12.6V and this was different to the leisure battey reading - no bother there. 2 things are suprising about this. The first is that the EC460 was sending power to the vehicle battery when powered off - perhaps it was using the PX300 to manage this and this ties into the 2nd point. The charging voltage showing on the Victron MPPT was 12.5 to 12.7V. Not the 13.3 I see when it is charging the leisure batteries via the EC460. Could you expect such a voltage drop on the cable getting the extra 2 to 4 meters to the vehicle battery?

How important is this - not massively but my head gets fried when I don't understand the small things. Learnt a lot from this site and hope to learn some more.

Thanks

 

[Diabalo]

I have a Sargent EC500 and that has a drain of 0.2A so that seems normal on yours. On mine if I put the EC500 into shut down mode like you there is no drain but on mine all the solar charge goes to the hab batteries, as you say yours does the opposite and charges the vehicle it would be worth checking the unit to see if the plugs are the correct way round, but it may be designed for it to do that.

12.5v-12.7v is battery rested voltage not a charging voltage, charging voltage would be around 14.2v for bulk then about 13.6v for float.

 

[Richard n Ann]

Our Elddis quiescent drain is also 0.2 amps. There will be a circuit board or 2 powered up somewhere, might be the heating or water heater. I did start looking for it the other year, it was shared down a couple of wires at the fuse box that went into the loom, I lost interest at that point, it's only 200ma.

 

[tonka]

Usual operation. On my Apache 700 with the EC500 I noticed exactly the same thing on the current drain.
I contacted Sargent and they confirmed that was normal. It's the reason why so many new owners have flat batteries so soon as they either dont have solar fitted or they dont set up the charger correctly.

Be aware that the Standby / shutdown MUST be left on for the Sargent unit to operate properly in Smart charge mode and do both batteries..

Sargent EC500 Smart charging

Sargent EC500 flow chart

www.motorhomefun.co.uk

 

[Insider]

Thanks for the replys people. It's a small draw but I hadn't noticed it before so was wondering. Good to know it's within parameters. Plan to double the solar and add a battery master at some stage but not doing it immediately as will have to route the solar directly into the hab batteries rather than through the EC460. Only just saw I had put some text into an attachment. Started the ticket and then left it for a few hours - my bad!!

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[Insider]

I have a Sargent EC500 and that has a drain of 0.2A so that seems normal on yours. On mine if I put the EC500 into shut down mode like you there is no drain but on mine all the solar charge goes to the hab batteries, as you say yours does the opposite and charges the vehicle it would be worth checking the unit to see if the plugs are the correct way round, but it may be designed for it to do that.

12.5v-12.7v is battery rested voltage not a charging voltage, charging voltage would be around 14.2v for bulk then about 13.6v for float.

Completely agree with you which is why I am perplexed as to why it was showing such a high wattage on the MPPT controller and the voltage was fluctuating. You can set the adsorption and float on a Victron MPPT. I don't think you can set the bulk voltage and that's why I was wondering.....but wait a minute...I have a wireless connection between the BMV and the MTTP controller - Victron proprietary -which normally would be better as the BMV is right next to the batteries and the MTTP controller is several meters away. This reports the voltage of the batteries back to the MTTP rather than the MTTP measuring it. I didn't disable that so the MTTP is being told the voltage of the hab battery while charging the leisure battery - that's not a good thing to do!!

My Victron nevers goes above 13.4V when charging the hab batteries normally. I had been expecting higher as you said but assume that Victron know what they are doing, espically as there doesn't seem to be a way of configuring it. I would like to know did I get something wrong with it somewhere.

 

[Diabalo]

I have the Victron Smart solar regulator and can change the charging parameters for bulk using the app, if you have a lead acid battery 13.4v is not high enough for bulk. There is a little cog on the app for settings and you can go into advanced and set as you wish.

If you have the shunt for the BMV712 between the hab batteries and the EC460 it will get confusing when the smart charging kicks in and changes over to charge the vehicle battery because the BMV712 will not be seeing it I believe. I have probably confused the issue more now.

 

[Insider]

I have the Victron Smart solar regulator and can change the charging parameters for bulk using the app, if you have a lead acid battery 13.4v is not high enough for bulk. There is a little cog on the app for settings and you can go into advanced and set as you wish.

If you have the shunt for the BMV712 between the hab batteries and the EC460 it will get confusing when the smart charging kicks in and changes over to charge the vehicle battery because the BMV712 will not be seeing it I believe. I have probably confused the issue more now.

Diabalo,

all understood - thanks. However I can't find where to set the bulk voltage as I would agree that 13.4V is too low for lead acid. Below are screenshots of the Victron interface on my phone. I don't believe there is a place to set the bulk voltage.

 

[cmcardle75]

Bulk charge is done at constant current, not constant voltage. There is no need for a set voltage. It will produce whatever voltage is required to get the 20A (or whatever the maximum current available is). Typically this will result in a gradual rise in voltage over time through the 13-14.4V range. Once it hits the absorbtion voltage, this will likely trigger the absorbtion mode and hold constant voltage reducing current for a set period (or until current drops low enough). It will then go into float charge, dropping the voltage to avoid overcharging.

 

[cmcardle75]

Bulk charge is done at constant current, not constant voltage. There is no need for a set voltage. It will produce whatever voltage is required to get the 20A (or whatever the maximum current available is). Typically this will result in a gradual rise in voltage over time through the 13-14.4V range. Once it hits the absorbtion voltage, this will likely trigger the absorbtion mode and hold constant voltage reducing current for a set period (or until current drops low enough). It will then go into float charge, dropping the voltage to avoid overcharging.

Also, on solar, there may not be enough current available to push through the bulk phase, especially in winter if there is any hab load. If this happens frequently, it can damage the battery. You should turn everything off and get a completed bulk phase through, (this may require EHU or a long drive with a B2B charger).

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[Lenny HB]

I also noticed your absorption phase is too long for wet cells 1 hour should be enough.

 

[Diabalo]

Insider,

CMcardle75 is probably right about Bulk settings I'm doing it by memory, I think your phone interface is different to mine, the problem is I can't see mine at the moment as nothing comes up when not connected to the controller and my van is in storage. It could be the absorption parameters I am getting mixed up with, even so I can manually change the settings but you wouldn't want to go over the14.40v that it's set up for now anyway. Next time I am up the van I will connect to the controller and have a look.

 

[Diabalo]

Lenny, Looking at my past data mine averages 1 hour in absorption but it can be as much as 2 hours and that is dictated by Victron solar controller.

That aside I think the OP problem is the same as mine, the battery monitoring shunt sampler is only between the hab batteries, the PSU when on smart solar charging switches from hab to vehicle charging after about 4 hours, so the solar controller charges up one battery then gets switched over to the other one that is in a different state of charge which then is confusing because the reading from the app for the charge controller is not going to show the same as the reading on the BMV712 battery monitor.

 

[Insider]

I also noticed your absorption phase is too long for wet cells 1 hour should be enough.

Lenny that 6hrs is the maximum absorption time. My understanding is that the Victron will only give it that much time after a deep discharge and shorten the time considerably for shallower discharges. That said I have never looked at my stats to examine is itdoing this so that box needs to get ticked. My van is not getting as much use as I would want so most of the discharges will be very shallow ATM.

Thanks

 

[Insider]

Bulk charge is done at constant current, not constant voltage. There is no need for a set voltage. It will produce whatever voltage is required to get the 20A (or whatever the maximum current available is). Typically this will result in a gradual rise in voltage over time through the 13-14.4V range. Once it hits the absorbtion voltage, this will likely trigger the absorbtion mode and hold constant voltage reducing current for a set period (or until current drops low enough). It will then go into float charge, dropping the voltage to avoid overcharging.

AND..... it seems so simple when someone comes along and explains it well which is a skill in itself. While the voltage is important the Victron is determing it for the bulk stage to get the current as high as possible - understood and thanks

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[Insider]

Also, on solar, there may not be enough current available to push through the bulk phase, especially in winter if there is any hab load. If this happens frequently, it can damage the battery. You should turn everything off and get a completed bulk phase through, (this may require EHU or a long drive with a B2B charger).

Can I ask - If I see the Victron go into absorption and then float can I assume that it has been able to get enough charge in?

 

[cmcardle75]

Can I ask - If I see the Victron go into absorption and then float can I assume that it has been able to get enough charge in?

Yes, if it gets to float, definitely. Some absorbtion is a lot better than none at all before it starts discharging again.

However, a knackered battery can look a lot like a much smaller healthy battery, so just getting to float doesn't mean your battery is good, is just means your charging setup is working and causing no further damage.

 

[Insider]

Yes, if it gets to float, definitely. Some absorbtion is a lot better than none at all before it starts discharging again.

However, a knackered battery can look a lot like a much smaller healthy battery, so just getting to float doesn't mean your battery is good, is just means your charging setup is working and causing no further damage.

Understood - thanks. I had my suspicions about the battery in the camper when I bought it so I put in 2xVarta LFD90s during the summer and at the same time put the BMV in so I would not over discharge them. I don't have any high current devices - the worst is the 300W inverter for my laptop. Coffee is made on the gas and my good wife hasn't used a hair drier in decades