14 Watt too much on caravan supply.

[ericmark]

The caravan draws 16W and if instead I use a Lidi charger that uses 2W so 14W over what expected, testing shows two things.

1) Sockets supply using 5W with nothing plugged in. Either 230 volt or 5 volt USB.
2) Charger using 11W, both built in and Lidi charger seems to hold battery at 13.7 volt.

So two things, one can 2 USB sockets draw 5W with nothing plugged in, they are either LAP or BG can't remember which, but I have this 16W draw before I fitted the last one.

So is either the charger or battery faulty to be drawing 11W? with main switch off and isolator off?

And is there something unknown switched on, or is 4 to 5W to two USB 13A sockets normal.

 

[DetlefSchmitz]

The obvious question is: how are you measuring this? I suspect the answer lies there.

 

[ericmark]

I have an Energenie MiHome plug in remote switch/energy meter monitoring what the caravan uses. Both MCB's off no power used, 10A MCB switched on 4 to 5 watt used, meter does not show point something watts. And with 6A MCB switched on 11W used, unplug the power connected to charger this drops to zero.

Using Lidi charger unlike caravan one this is a stage charger, so at 12 volt it is 3.8A, 3A, 0.8A, 0.1A or off, watching the energy meter one can see the input to charger match these outputs plus a little, so 60W, 45W, 14W, 2W and zero. Within a minute it has gone to 2W, if left it will every so often jump to 14W but software averages it out at around 3 to 4 watt.

If the caravan charger is simply inefficient, then not really worth removing battery to just gain around 7W, but if there is some thing wrong, better to do it now, not while on holiday.

The same applies with socket supply, 3 sockets, microwave (1215W when running no display simple clockwork knobs), and room heater from same (10A) MCB, I have tested 565W, 1065W or 2085W depending on setting, fans are 12 volt so other MCB. There are no 230 volt lights, but circuit diagram shows two. The charger and water heater both are fed from the 6A MCB and water heater shows 480W when switched on and fridge 140W.

There are errors on the circuit diagram, and I have been trying to work out what everything does, the battery charger seems to match any power used, so switching on radio you see the power used jump by 7W for example, I have been using this to see what switches what when the item can't be seen to work, only items I can't see current used is ignition for gas and 12 volt fridge, the latter is only powered from car battery.

I have two fuses not a clue what they do, one is not live, tried fridge off 7 Ah battery for few minutes in case it supplied that, but it does not, and a blue cable from other fuse powered up all the time not through main switch again not a clue what it does. There are 14 fuses, one not used, was radio, and 12 labels both even spaced, so it seems at some point a replacement fuse/relay board has been fitted. Cable colours don't match circuit diagram.

When in Forest of Dean camping site there was no internet and the RCD was tripping when the 10A MCB was switched on, with no meters I was trying to find the fault, next day fault went and when I got it home it showed no faults so never did find out why. So now multi-meter and insulation tested is kept in the caravan, and I have been trying to work out what everything does. Then if no internet when it fails again, I at least have some info to help, I actually bought a second Lidi charger because I thought battery was not being charged and maybe charger faulty, in fact charger was supplied from MCB which did not trip the RCD.

The meter which will measure DC amps jumps from 100 mA range to 10A range, so 11W is around the amp, and meter needle moves that little can't really see how much charge. Other meter is AC only for amps. Seems I need to find out old AVO Mk8 but not sure of ranges on that now, it has not been used for years.

 

[DetlefSchmitz]

Most plug-in monitors are very inaccurate at low power and especially with sinks with non-unity power factors. Without a more accurate measurement I would be inclined to ignore this. No measurement that doesn't take power factor into account is much use to you.

 

[SimonH2]

Looking at the Energenie UK website, I would have a rather low expectation given that they can't be bothered to provide anything resembling technical specs, and their "whole home" monitor appears to be a current only monitor.

 

[JohnW2]

Most plug-in monitors are very inaccurate at low power and especially with sinks with non-unity power factors. Without a more accurate measurement I would be inclined to ignore this. No measurement that doesn't take power factor into account is much use to you.

Agreed - but, in my experience, the plug-in ones almost always do take PF (and voltage) into account. I have a couple of very cheap ones and not only do both of them 'take PF into account', but they actually display it (if asked). It's the 'clip on' ('clamp') ones that are the problem since, if that's all they have, they clearly cannot know anything about either voltage or PF - so, at best, they only try to display VA (although they usually call it Watts), but even the VA is inaccurate, since they don't know the actual 'V'.

How accurate they are at very low currents is a different matter - but, again, I would expect them to be much better in that respect than 'clip-on' ones.

Kind Regards, John

 

[DetlefSchmitz]

So you think that a socket (+usb skt) with nothing plugged in is using 5W?

 

[JohnW2]

So you think that a socket (+usb skt) with nothing plugged in is using 5W?

One would certainly hope not. Eric does have two USB sockets but. for example, the MK ones claim a standby power of only 0.15W, hence 0.3W for two. However, as I said ...

How accurate they are at very low currents is a different matter ....

Kind Regards, John

 

[DetlefSchmitz]

Actually that is what I said in post 4. You seem to be arguing for the sake of it. Come di solito.

 

[JohnW2]

Actually that is what I said in post 4.

Yes, you did. As you've seen, I agree with what you said in the first sentence of that post.

You seem to be arguing for the sake of it. Come di solito.

I was commenting about (not arguing with - the first word of my response was "Agreed") the second sentence of what you wrote in post #4 (which is what I quoted), namely ...

... No measurement that doesn't take power factor into account is much use to you.

Kind Regards, John

 

[DetlefSchmitz]

As you then went on to agree, a measurement that reads 5W for an empty socket is not much use. As it reads zero when disconnected it seems more likely that power factor, rather than absolute accuracy, is the culprit

 

[JohnW2]

As you then went on to agree, a measurement that reads 5W for an empty socket is not much use. As it reads zero when disconnected it seems more likely that power factor, rather than absolute accuracy, is the culprit

You're obviously free to speculate about the mechanism of the apparent error. I just don't know, but ....

As I said, these things usually 'take PF into account'. However, even if it were reporting VA, if the actual current were, say, 0.3W (per MK) (about 1.3mA), then for it to display "5W" (about 22mA) (actually VA, because it hadn't taken PF into account), that would imply a PF of around 0.06, which would seem pretty (very?) unlikely.

Kind Regards, John

 

[ban-all-sheds]

Looking at the Energenie UK website, I would have a rather low expectation given that they can't be bothered to provide anything resembling technical specs, and their "whole home" monitor appears to be a current only monitor.

Surely you've got one of those the wrong way round?

Either you have a low expectation that they can be bothered, or you have a high expectation that they can't?

 

[ericmark]

The easy way is I will plug in a non internet connected Meter and compare readings.

 

[ericmark]

The obvious question is: how are you measuring this? I suspect the answer lies there.

Yes you were spot on. When I used the stand alone meter I found a series of pulses. Which had clearly upset the other meter.

I was getting two wattage reading too short to see what they were peaking at around 24 watt, and a power factor of around 0.75. Unfortunately the other meter needs two LR44 batteries to record the readings and I could not find any.